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Hill D, Conte L, Nelson D, Hammond J, Bell L. Investigating the water availability hypothesis of pot binding: small pots and infrequent irrigation confound the effects of drought stress in potato ( Solanum tuberosum L.). FRONTIERS IN PLANT SCIENCE 2024; 15:1399250. [PMID: 38938631 PMCID: PMC11208687 DOI: 10.3389/fpls.2024.1399250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Accepted: 05/20/2024] [Indexed: 06/29/2024]
Abstract
To maximise the throughput of novel, high-throughput phenotyping platforms, many researchers have utilised smaller pot sizes to increase the number of biological replicates that can be grown in spatially limited controlled environments. This may confound plant development through a process known as "pot binding", particularly in larger species including potato (Solanum tuberosum), and under water-restricted conditions. We aimed to investigate the water availability hypothesis of pot binding, which predicts that small pots have insufficient water holding capacities to prevent drought stress between irrigation periods, in potato. Two cultivars of potato were grown in small (5 L) and large (20 L) pots, were kept under polytunnel conditions, and were subjected to three irrigation frequencies: every other day, daily, and twice daily. Plants were phenotyped with two Phenospex PlantEye F500s and canopy and tuber fresh mass and dry matter were measured. Increasing irrigation frequency from every other day to daily was associated with a significant increase in fresh tuber yield, but only in large pots. This suggests a similar level of drought stress occurred between these treatments in the small pots, supporting the water availability hypothesis of pot binding. Further increasing irrigation frequency to twice daily was still not sufficient to increase yields in small pots but it caused an insignificant increase in yield in the larger pots, suggesting some pot binding may be occurring in large pots under daily irrigation. Canopy temperatures were significantly higher under each irrigation frequency in the small pots compared to large pots, which strongly supports the water availability hypothesis as higher canopy temperatures are a reliable indicator of drought stress in potato. Digital phenotyping was found to be less accurate for larger plants, probably due to a higher degree of self-shading. The research demonstrates the need to define the optimum pot size and irrigation protocols required to completely prevent pot binding and ensure drought treatments are not inadvertently applied to control plants.
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Affiliation(s)
- Dominic Hill
- School of Agriculture, Policy and Development, University of Reading, Reading, United Kingdom
| | - Lorenzo Conte
- School of Agriculture, Policy and Development, University of Reading, Reading, United Kingdom
| | | | - John Hammond
- School of Agriculture, Policy and Development, University of Reading, Reading, United Kingdom
| | - Luke Bell
- School of Agriculture, Policy and Development, University of Reading, Reading, United Kingdom
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2
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Feng L, Shuai L, Zhou Y, Zhang X, Sun J. Improving the green space arrangement in residential areas from the perspective of tree leaf temperature utilizing scenario simulation in ENVI-met. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 918:170650. [PMID: 38320699 DOI: 10.1016/j.scitotenv.2024.170650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 01/30/2024] [Accepted: 01/31/2024] [Indexed: 02/12/2024]
Abstract
Studying the differences in leaf temperature and their mechanisms can help us accurately understand the microenvironment in which plants are located. In this paper, typical residential areas in Jianye District, Nanjing, Jiangsu Province, China, are selected as the research area, we investigated the suitability of green space configurations from the perspective of tree leaf temperature of residential areas based on the scenario simulation in ENVI-met. Firstly, twenty abstract models were constructed, including four kinds of aspect ratio of trees (ARTs) which can be used to indicate the different green space arrangement and two typical tree species, camphora tree and platanus tree. And then three aspects were discussed including impacts of different Aspect Ratio of Trees (ART), different house-side configurations on tree leaf temperature and the relationship between temperature of tree leaves and land surface temperature (ΔSurfT) and the thermal comfort index of physiological equivalent temperature (ΔPET). The results showed that B-1 (camphor tree, ART = 2) demonstrates the most effective cooling effect in summer, with ΔPET of 3.09 °C and ΔSurfT of 3.34 °C. In winter, A-1 (platanus tree, ART = 2) proves to be the most effective in enhancing thermal comfort (ΔPET = -0.15 °C), while B-1 excels in improving surface temperature (ΔSurfT = 0.55 °C). In all, for residential area, especially in summer, planting dense camphora trees is better than platanus trees and house-side green space was very necessary. This research can help to determine appropriate tree species and green space configuration strategies for future residential areas to enhance thermal comfort.
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Affiliation(s)
- Li Feng
- College of Geography and Remote Sensing, Hohai University, Nanjing 211100, China.
| | - Linru Shuai
- College of Geography and Remote Sensing, Hohai University, Nanjing 211100, China
| | - Yanan Zhou
- College of Geography and Remote Sensing, Hohai University, Nanjing 211100, China.
| | - Xiao Zhang
- College of Geography and Remote Sensing, Hohai University, Nanjing 211100, China
| | - Jiaxin Sun
- College of Geography and Remote Sensing, Hohai University, Nanjing 211100, China
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3
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Diao H, Cernusak LA, Saurer M, Gessler A, Siegwolf RTW, Lehmann MM. Uncoupling of stomatal conductance and photosynthesis at high temperatures: mechanistic insights from online stable isotope techniques. THE NEW PHYTOLOGIST 2024; 241:2366-2378. [PMID: 38303410 DOI: 10.1111/nph.19558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 01/12/2024] [Indexed: 02/03/2024]
Abstract
The strong covariation of temperature and vapour pressure deficit (VPD) in nature limits our understanding of the direct effects of temperature on leaf gas exchange. Stable isotopes in CO2 and H2 O vapour provide mechanistic insight into physiological and biochemical processes during leaf gas exchange. We conducted combined leaf gas exchange and online isotope discrimination measurements on four common European tree species across a leaf temperature range of 5-40°C, while maintaining a constant leaf-to-air VPD (0.8 kPa) without soil water limitation. Above the optimum temperature for photosynthesis (30°C) under the controlled environmental conditions, stomatal conductance (gs ) and net photosynthesis rate (An ) decoupled across all tested species, with gs increasing but An decreasing. During this decoupling, mesophyll conductance (cell wall, plasma membrane and chloroplast membrane conductance) consistently and significantly decreased among species; however, this reduction did not lead to reductions in CO2 concentration at the chloroplast surface and stroma. We question the conventional understanding that diffusional limitations of CO2 contribute to the reduction in photosynthesis at high temperatures. We suggest that stomata and mesophyll membranes could work strategically to facilitate transpiration cooling and CO2 supply, thus alleviating heat stress on leaf photosynthetic function, albeit at the cost of reduced water-use efficiency.
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Affiliation(s)
- Haoyu Diao
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, 8903, Switzerland
| | - Lucas A Cernusak
- College of Science and Engineering, James Cook University, Cairns, Qld, 4879, Australia
| | - Matthias Saurer
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, 8903, Switzerland
| | - Arthur Gessler
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, 8903, Switzerland
- Institute of Terrestrial Ecosystems, ETH Zurich, Zurich, 8092, Switzerland
| | - Rolf T W Siegwolf
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, 8903, Switzerland
| | - Marco M Lehmann
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, 8903, Switzerland
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4
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Kullberg AT, Coombs L, Soria Ahuanari RD, Fortier RP, Feeley KJ. Leaf thermal safety margins decline at hotter temperatures in a natural warming 'experiment' in the Amazon. THE NEW PHYTOLOGIST 2024; 241:1447-1463. [PMID: 37984063 DOI: 10.1111/nph.19413] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 10/28/2023] [Indexed: 11/22/2023]
Abstract
The threat of rising global temperatures may be especially pronounced for low-latitude, lowland plant species that have evolved under stable climatic conditions. However, little is known about how these species may acclimate to elevated temperatures. Here, we leveraged a strong, steep thermal gradient along a natural geothermal river to assess the ability of woody plants in the Amazon to acclimate to elevated air temperatures. We measured leaf traits in six common tropical woody species along the thermal gradient to investigate whether individuals of these species: acclimate their thermoregulatory traits to maintain stable leaf temperatures despite higher ambient temperatures; acclimate their photosynthetic thermal tolerances to withstand hotter leaf temperatures; and whether acclimation is sufficient to maintain stable leaf thermal safety margins (TSMs) across different growth temperatures. Individuals of three species acclimated their thermoregulatory traits, and three species increased their thermal tolerances with growth temperature. However, acclimation was generally insufficient to maintain constant TSMs. Notwithstanding, leaf health was generally consistent across growth temperatures. Acclimation in woody Amazonian plants is generally too weak to maintain TSMs at high growth temperatures, supporting previous findings that Amazonian plants will be increasingly vulnerable to thermal stress as temperatures rise.
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Affiliation(s)
- Alyssa T Kullberg
- Department of Biology, University of Miami, Coral Gables, FL, 33146, USA
| | - Lauren Coombs
- Hussman Institute of Human Genomics, University of Miami Miller School of Medicine, Miami, FL, 33136, USA
| | - Roy D Soria Ahuanari
- Herbario Regional de Ucayali IVITA, Pucallpa (HRUIP), Universidad Nacional Mayor de San Marcos, Pucallpa, 25001, Peru
| | - Riley P Fortier
- Department of Biology, University of Miami, Coral Gables, FL, 33146, USA
| | - Kenneth J Feeley
- Department of Biology, University of Miami, Coral Gables, FL, 33146, USA
- Fairchild Tropical Botanic Garden, Coral Gables, FL, 33156, USA
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Vleminckx J, Hogan JA, Metz MR, Comita LS, Queenborough SA, Wright SJ, Valencia R, Zambrano M, Garwood NC. Flower production decreases with warmer and more humid atmospheric conditions in a western Amazonian forest. THE NEW PHYTOLOGIST 2024; 241:1035-1046. [PMID: 37984822 DOI: 10.1111/nph.19388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 10/18/2023] [Indexed: 11/22/2023]
Abstract
Climate models predict that everwet western Amazonian forests will face warmer and wetter atmospheric conditions, and increased cloud cover. It remains unclear how these changes will impact plant reproductive performance, such as flowering, which plays a central role in sustaining food webs and forest regeneration. Warmer and wetter nights may cause reduced flower production, via increased dark respiration rates or alteration in the reliability of flowering cue-based processes. Additionally, more persistent cloud cover should reduce the amounts of solar irradiance, which could limit flower production. We tested whether interannual variation in flower production has changed in response to fluctuations in irradiance, rainfall, temperature, and relative humidity over 18 yrs in an everwet forest in Ecuador. Analyses of 184 plant species showed that flower production declined as nighttime temperature and relative humidity increased, suggesting that warmer nights and greater atmospheric water saturation negatively impacted reproduction. Species varied in their flowering responses to climatic variables but this variation was not explained by life form or phylogeny. Our results shed light on how plant communities will respond to climatic changes in this everwet region, in which the impacts of these changes have been poorly studied compared with more seasonal Neotropical areas.
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Affiliation(s)
- Jason Vleminckx
- Department of Biology of Organisms, Université Libre de Bruxelles, Brussels, 1050, Belgium
- Yale Institute for Biospheric Studies, Yale University, New Haven, CT, 06511, USA
- School of the Environment, Yale University, New Haven, CT, 06511, USA
| | - J Aaron Hogan
- Department of Biology, University of Florida, Gainesville, FL, 32611, USA
| | - Margaret R Metz
- Department of Biology, Lewis & Clark College, Portland, OR, 97219, USA
| | - Liza S Comita
- School of the Environment, Yale University, New Haven, CT, 06511, USA
| | | | - S Joseph Wright
- Smithsonian Tropical Research Institute, Apartado, Balboa, 0843-03092, Panama
| | - Renato Valencia
- Escuela de Ciencias Biológicas, Pontificia Universidad Católica del Ecuador, Quito, 170143, Ecuador
| | - Milton Zambrano
- Escuela de Ciencias Biológicas, Pontificia Universidad Católica del Ecuador, Quito, 170143, Ecuador
| | - Nancy C Garwood
- School of Biological Sciences, Southern Illinois University, Carbondale, IL, 62901, USA
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Zhang S, Ye H, Kong L, Li X, Chen Y, Wang S, Liu B. Multivariate Analysis Compares and Evaluates Heat Tolerance of Potato Germplasm. PLANTS (BASEL, SWITZERLAND) 2024; 13:142. [PMID: 38202450 PMCID: PMC10781149 DOI: 10.3390/plants13010142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 12/12/2023] [Accepted: 12/15/2023] [Indexed: 01/12/2024]
Abstract
High temperature is the most important environmental factor limiting potato (Solanum tuberosum L.) yield. The tuber yield has been used to evaluate the heat tolerance of some potato cultivars, but potato yield was closely correlated with the maturation period. Therefore, it is necessary to employ different parameters to comprehensively analyze and evaluate potato tolerance to heat stress. This study aimed to investigate physiologic changes during growth and development, and develop accurate heat tolerance evaluation methods of potato cultivars under heat stress. About 93 cultivars (including foreign elite lines, local landraces and cultivars) were screened using an in vitro tuber-inducing system (continuous darkness and 8% sucrose in the culture medium) under heat stress (30 °C) and normal (22 °C) conditions for 30 days. The tuber yield and number decreased significantly under heat stress compared to the control. A total of 42 cultivars were initially selected depending on tuber formation, after in vitro screening, further testing of selected cultivars was conducted in ex vitro conditions. The screened cultivars were further exposed to heat stress (35 °C/28 °C, day/night) for 60 days. Heat stress led to an increase in the plant height growth rate, fourth internode growth rate, and membrane damage, and due to heat-induced damage to chloroplasts, decrease in chlorophyll biosynthesis and photosynthetic efficiency. Three principal components were extracted by principal component analysis. Correlation and regression analysis showed that heat tolerance is positively correlated with the plant height growth rate, fourth internode growth rate, the content of chlorophyll b, photosynthetic rate, stomatal conductance, transpiration rate, tuber number, and tuber yield, and negatively correlated with the cell membrane injury level. The nine traits are accurate and representative indicators for evaluating potato tolerance to heat stress and could determine a relatively high mean forecast accuracy of 100.0% for the comprehensive evaluation value. Through cluster analysis and screening, cultivar FA, D73, and C132 had the highest heat comprehensive evaluation value, which could be further selected as heat-resistant varieties. This study provides insights into the different physiological mechanisms and accurate evaluation methods of potato cultivars under heat stress, which could be valuable for further research and breeding.
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Affiliation(s)
- Sujie Zhang
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Agronomy, Northwest A&F University, Yangling 712100, China
| | - Han Ye
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Agronomy, Northwest A&F University, Yangling 712100, China
- Shenzhen Research Institute, Northwest A&F University, Shenzhen 518000, China
| | - Lingshuang Kong
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Agronomy, Northwest A&F University, Yangling 712100, China
| | - Xiaoyu Li
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Agronomy, Northwest A&F University, Yangling 712100, China
| | - Yeqing Chen
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Agronomy, Northwest A&F University, Yangling 712100, China
| | - Shipeng Wang
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Agronomy, Northwest A&F University, Yangling 712100, China
| | - Bailin Liu
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Agronomy, Northwest A&F University, Yangling 712100, China
- Shenzhen Research Institute, Northwest A&F University, Shenzhen 518000, China
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7
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Schepers JR, Heblack J, Willi Y. Negative interaction effect of heat and drought stress at the warm end of species distribution. Oecologia 2024; 204:173-185. [PMID: 38253704 PMCID: PMC10830594 DOI: 10.1007/s00442-023-05497-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 12/10/2023] [Indexed: 01/24/2024]
Abstract
Geographic range limits of species are often a reflection of their ecological niche limits. In many organisms, important niche limits that coincide with distribution limits are warm and warm-dry conditions. We investigated the effects of heat and drought, as they can occur at the warm end of distribution. In a greenhouse experiment, we raised North American Arabidopsis lyrata from the centre of its distribution as well as from low- and high-latitude limits under average and extreme conditions. We assessed plant growth and development, as well as leaf and root functional traits, and tested for a decline in performance and selection acting on growth, leaf, and root traits. Drought and heat, when applied alone, lowered plant performance, while combined stress caused synergistically negative effects. Plants from high latitudes did not survive under combined stress, whereas plants originating from central and low latitudes had low to moderate survival, indicating divergent adaptation. Traits positively associated with survival under drought, with or without heat, were delayed and slowed growth, though plastic responses in these traits were generally antagonistic to the direction of selection. In line, higher tolerance of stress in southern populations did not involve aspects of growth but rather a higher root-to-shoot ratio and thinner leaves. In conclusion, combined heat and drought, as can occur at southern range edges and presumably more so under global change, seriously impede the long-term persistence of A. lyrata, even though they impose selection and populations may adapt, though under likely interference by considerable maladaptive plasticity.
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Affiliation(s)
- Judith R Schepers
- Department of Environmental Sciences, University of Basel, 4056, Basel, Switzerland.
| | - Jessica Heblack
- Department of Environmental Sciences, University of Basel, 4056, Basel, Switzerland
| | - Yvonne Willi
- Department of Environmental Sciences, University of Basel, 4056, Basel, Switzerland
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8
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Chen X, Li J, Peñuelas J, Li X, Hu D, Wang M, Zhong Q, Cheng D. Temperature dependence of carbon metabolism in the leaves in sun and shade in a subtropical forest. Oecologia 2024; 204:59-69. [PMID: 38091103 DOI: 10.1007/s00442-023-05487-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Accepted: 11/15/2023] [Indexed: 02/02/2024]
Abstract
Rising temperatures pose a threat to the stability of climate regulation by carbon metabolism in subtropical forests. Although the effects of temperature on leaf carbon metabolism traits in sun-exposed leaves are well understood, there is limited knowledge about its impacts on shade leaves and the implications for ecosystem-climate feedbacks. In this study, we measured temperature response curves of photosynthesis and respiration for 62 woody species in summer (including both evergreen and deciduous species) and 20 evergreen species in winter. The aim was to uncover the temperature dependence of carbon metabolism in both sun and shade leaves in subtropical forests. Our findings reveal that shade had no significant effects on the mean optimum photosynthetic temperatures (TOpt) or temperature range (T90). However, there were decreases observed in mean stomatal conductance, mean area-based photosynthetic rates at TOpt and 25 °C, as well as mean area-based dark respiration rates at 25 °C in both evergreen and deciduous species. Moreover, the respiration-temperature sensitivity (Q10) of sun leaves was higher than that of shade leaves in winter, with the reverse being true in summer. Leaf economics spectrum traits, such as leaf mass per area, and leaf concentration of nitrogen and phosphorus across species, proved to be good predictors of TOpt, T90, mass-based photosynthetic rate at TOpt, and mass-based photosynthetic and respiration rate at 25 °C. However, Q10 was poorly predicted by these leaf economics spectrum traits except for shade leaves in winter. Our results suggest that model estimates of carbon metabolism in multilayered subtropical forest canopies do not necessitate independent parameterization of T90 and TOpt temperature responses in sun and shade leaves. Nevertheless, a deeper understanding and quantification of canopy variations in Q10 responses to temperature are necessary to confirm the generality of temperature-carbon metabolism trait responses and enhance ecosystem model estimates of carbon dynamics under future climate warming.
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Affiliation(s)
- Xiaoping Chen
- Key Laboratory of Humid Subtropical Eco-Geographical Process (Ministry of Education), College of Geographical Sciences, Fujian Normal University, Fuzhou, China
- College of Tourism, Resources and Environment, Zaozhuang University, Zaozhuang, Shandong, China
- Fujian Provincial Key Laboratory of Plant Ecophysiology, College of Geographical Sciences, Fujian Normal University, Fuzhou, China
| | - Jinlong Li
- Key Laboratory of Humid Subtropical Eco-Geographical Process (Ministry of Education), College of Geographical Sciences, Fujian Normal University, Fuzhou, China
- Fujian Provincial Key Laboratory of Plant Ecophysiology, College of Geographical Sciences, Fujian Normal University, Fuzhou, China
| | - Josep Peñuelas
- Global Ecology Unit, CSIC, CREAF-CSIC-UAB, 08193, Bellaterra, Catalonia, Spain
- CREAF, 08193, Cerdanyola del Vallès, Catalonia, Spain
| | - Xueqin Li
- Key Laboratory of Humid Subtropical Eco-Geographical Process (Ministry of Education), College of Geographical Sciences, Fujian Normal University, Fuzhou, China
- Fujian Provincial Key Laboratory of Plant Ecophysiology, College of Geographical Sciences, Fujian Normal University, Fuzhou, China
| | - Dandan Hu
- Key Laboratory of Humid Subtropical Eco-Geographical Process (Ministry of Education), College of Geographical Sciences, Fujian Normal University, Fuzhou, China
- Fujian Provincial Key Laboratory of Plant Ecophysiology, College of Geographical Sciences, Fujian Normal University, Fuzhou, China
| | - Mantang Wang
- College of Tourism, Resources and Environment, Zaozhuang University, Zaozhuang, Shandong, China
| | - Quanlin Zhong
- Key Laboratory of Humid Subtropical Eco-Geographical Process (Ministry of Education), College of Geographical Sciences, Fujian Normal University, Fuzhou, China
- Fujian Provincial Key Laboratory of Plant Ecophysiology, College of Geographical Sciences, Fujian Normal University, Fuzhou, China
| | - Dongliang Cheng
- Key Laboratory of Humid Subtropical Eco-Geographical Process (Ministry of Education), College of Geographical Sciences, Fujian Normal University, Fuzhou, China.
- Fujian Provincial Key Laboratory of Plant Ecophysiology, College of Geographical Sciences, Fujian Normal University, Fuzhou, China.
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Liu M, Zhou Y, Sun J, Mao F, Yao Q, Li B, Wang Y, Gao Y, Dong X, Liao S, Wang P, Huang S. From the floret to the canopy: High temperature tolerance during flowering. PLANT COMMUNICATIONS 2023; 4:100629. [PMID: 37226443 PMCID: PMC10721465 DOI: 10.1016/j.xplc.2023.100629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 04/29/2023] [Accepted: 05/22/2023] [Indexed: 05/26/2023]
Abstract
Heat waves induced by climate warming have become common in food-producing regions worldwide, frequently coinciding with high temperature (HT)-sensitive stages of many crops and thus threatening global food security. Understanding the HT sensitivity of reproductive organs is currently of great interest for increasing seed set. The responses of seed set to HT involve multiple processes in both male and female reproductive organs, but we currently lack an integrated and systematic summary of these responses for the world's three leading food crops (rice, wheat, and maize). In the present work, we define the critical high temperature thresholds for seed set in rice (37.2°C ± 0.2°C), wheat (27.3°C ± 0.5°C), and maize (37.9°C ± 0.4°C) during flowering. We assess the HT sensitivity of these three cereals from the microspore stage to the lag period, including effects of HT on flowering dynamics, floret growth and development, pollination, and fertilization. Our review synthesizes existing knowledge about the effects of HT stress on spikelet opening, anther dehiscence, pollen shedding number, pollen viability, pistil and stigma function, pollen germination on the stigma, and pollen tube elongation. HT-induced spikelet closure and arrest of pollen tube elongation have a catastrophic effect on pollination and fertilization in maize. Rice benefits from pollination under HT stress owing to bottom anther dehiscence and cleistogamy. Cleistogamy and secondary spikelet opening increase the probability of pollination success in wheat under HT stress. However, cereal crops themselves also have protective measures under HT stress. Lower canopy/tissue temperatures compared with air temperatures indicate that cereal crops, especially rice, can partly protect themselves from heat damage. In maize, husk leaves reduce inner ear temperature by about 5°C compared with outer ear temperature, thereby protecting the later phases of pollen tube growth and fertilization processes. These findings have important implications for accurate modeling, optimized crop management, and breeding of new varieties to cope with HT stress in the most important staple crops.
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Affiliation(s)
- Mayang Liu
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Yuhan Zhou
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Jiaxin Sun
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Fen Mao
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Qian Yao
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Baole Li
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Yuanyuan Wang
- College of Agronomy, South China Agricultural University, Guangdong, China
| | - Yingbo Gao
- Shandong Academy of Agricultural Sciences, Jinan, China
| | - Xin Dong
- Chongqing Academy of Agricultural Sciences, Chongqing, China
| | - Shuhua Liao
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Pu Wang
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Shoubing Huang
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, China.
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10
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Sun T, Zhang X, Lv S, Lin X, Ma J, Liu J, Fang Q, Tang L, Liu L, Cao W, Liu B, Zhu Y. Improving the predictions of leaf photosynthesis during and after short-term heat stress with current rice models. PLANT, CELL & ENVIRONMENT 2023; 46:3353-3370. [PMID: 37575035 DOI: 10.1111/pce.14683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/26/2023] [Accepted: 07/31/2023] [Indexed: 08/15/2023]
Abstract
In response to increasing global warming, extreme heat stress significantly alters photosynthetic production. While numerous studies have investigated the temperature effects on photosynthesis, factors like vapour pressure deficit (VPD), leaf nitrogen, and feedback of sink limitation during and after extreme heat stress remain underexplored. This study assessed photosynthesis calculations in seven rice growth models using observed maximum photosynthetic rate (Pmax ) during and after short-term extreme heat stress in multi-year environment-controlled experiments. Biochemical models (FvCB-type) outperformed light response curve-based models (LRC-type) when incorporating observed leaf nitrogen, photosynthetically active radiation, temperatures, and intercellular CO2 concentration (Ci ) as inputs. Prediction uncertainty during heat stress treatment primarily resulted from variation in temperatures and Ci . Improving FVPD (the slope for the linear effect of VPD on Ci /Ca ) to be temperature-dependent, rather than constant as in original models, significantly improved Ci prediction accuracy under heat stress. Leaf nitrogen response functions led to model variation in leaf photosynthesis predictions after heat stress, which was mitigated by calibrated nitrogen response functions based on active photosynthetic nitrogen. Additionally, accounting for observed differences in carbohydrate accumulation between panicles and stems during grain filling improved the feedback of sink limitation, reducing Ci overestimation under heat stress treatments.
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Affiliation(s)
- Ting Sun
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
- Key Laboratory of Specialty Agri-product Quality and Hazard Controlling Technology of Zhejiang Province, College of Life Sciences, China Jiliang University, Hangzhou, Zhejiang, China
| | - Xiaohu Zhang
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Suyu Lv
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Xuanhao Lin
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Jifeng Ma
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Jiaming Liu
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Qizhao Fang
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Liang Tang
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Leilei Liu
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Weixing Cao
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Bing Liu
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Yan Zhu
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, College of Agriculture, Nanjing Agricultural University, Nanjing, Jiangsu, China
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11
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Tran KN, Pantha P, Wang G, Kumar N, Wijesinghege C, Oh DH, Wimalagunasekara S, Duppen N, Li H, Hong H, Johnson JC, Kelt R, Matherne MG, Nguyen TT, Garcia JR, Clement A, Tran D, Crain C, Adhikari P, Zhang Y, Foroozani M, Sessa G, Larkin JC, Smith AP, Longstreth D, Finnegan P, Testerink C, Barak S, Dassanayake M. Balancing growth amidst salt stress - lifestyle perspectives from the extremophyte model Schrenkiella parvula. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 116:921-941. [PMID: 37609706 DOI: 10.1111/tpj.16396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 07/08/2023] [Indexed: 08/24/2023]
Abstract
Schrenkiella parvula, a leading extremophyte model in Brassicaceae, can grow and complete its lifecycle under multiple environmental stresses, including high salinity. Yet, the key physiological and structural traits underlying its stress-adapted lifestyle are unknown along with trade-offs when surviving salt stress at the expense of growth and reproduction. We aimed to identify the influential adaptive trait responses that lead to stress-resilient and uncompromised growth across developmental stages when treated with salt at levels known to inhibit growth in Arabidopsis and most crops. Its resilient growth was promoted by traits that synergistically allowed primary root growth in seedlings, the expansion of xylem vessels across the root-shoot continuum, and a high capacity to maintain tissue water levels by developing thicker succulent leaves while enabling photosynthesis during salt stress. A successful transition from vegetative to reproductive phase was initiated by salt-induced early flowering, resulting in viable seeds. Self-fertilization in salt-induced early flowering was dependent upon filament elongation in flowers otherwise aborted in the absence of salt during comparable plant ages. The maintenance of leaf water status promoting growth, and early flowering to ensure reproductive success in a changing environment, were among the most influential traits that contributed to the extremophytic lifestyle of S. parvula.
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Affiliation(s)
- Kieu-Nga Tran
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
| | - Pramod Pantha
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
| | - Guannan Wang
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
| | - Narender Kumar
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
| | - Chathura Wijesinghege
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
| | - Dong-Ha Oh
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
| | - Samadhi Wimalagunasekara
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
| | - Nick Duppen
- Albert Katz International School for Desert Studies, Ben-Gurion University of the Negev, Sde Boqer Campus, Beersheba, 8499000, Israel
| | - Hongfei Li
- Laboratory of Plant Physiology, Plant Sciences Group, Wageningen University and Research, 6708PB, Wageningen, The Netherlands
| | - Hyewon Hong
- Department of Plant Biology, University of Illinois, Urbana-Champaign, Illinois, 61801, USA
| | - John C Johnson
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
| | - Ross Kelt
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
| | - Megan G Matherne
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
| | - Thu T Nguyen
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
| | - Jason R Garcia
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
| | - Ashley Clement
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
| | - David Tran
- Department of Biochemistry & Department of Psychology, University of Miami, Coral Gables, Florida, 33146, USA
| | - Colt Crain
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
- Louisiana School for Math, Science and the Arts, Natchitoches, Louisiana, 71457, USA
| | - Prava Adhikari
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
| | - Yanxia Zhang
- Laboratory of Plant Physiology, Plant Sciences Group, Wageningen University and Research, 6708PB, Wageningen, The Netherlands
| | - Maryam Foroozani
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
| | - Guido Sessa
- School of Plant Sciences and Food Security, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - John C Larkin
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
| | - Aaron P Smith
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
| | - David Longstreth
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
| | - Patrick Finnegan
- School of Biological Sciences, University of Western Australia, Perth, 6009, Australia
| | - Christa Testerink
- Laboratory of Plant Physiology, Plant Sciences Group, Wageningen University and Research, 6708PB, Wageningen, The Netherlands
| | - Simon Barak
- French Associates' Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sde Boqer Campus, Beersheba, 8499000, Israel
| | - Maheshi Dassanayake
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
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12
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Sheeran L, Rasmussen A. Aerial roots elevate indoor plant health: Physiological and morphological responses of three high-humidity adapted Araceae species to indoor humidity levels. PLANT, CELL & ENVIRONMENT 2023; 46:1873-1884. [PMID: 36786325 DOI: 10.1111/pce.14568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 02/10/2023] [Accepted: 02/12/2023] [Indexed: 05/04/2023]
Abstract
Heightened by the COVID-19 pandemic there has been a global increase in urban greenspace appreciation. Indoor plants are equally important for improving mental health and air quality but despite evolving in humid (sub)tropical environments with aerial root types, planting systems ignore aerial resource supply. This study directly compared nutrient uptake preferences of aerial and soil-formed roots of three common houseplant species under high and ambient relative humidities. Growth and physiology parameters were measured weekly for Anthurium andreanum, Epipremnum aureum and Philodendron scandens grown in custom made growth chambers. Both aerial and soil-formed roots were then fed mixtures of nitrate, ammonium and glycine, with one source labelled with 15 N to determine uptake rates and maximum capacities. Aerial roots were consistently better at nitrogen uptake than soil roots but no species, root type or humidity condition showed a preference for a particular nitrogen source. All three species grew more in high humidity, with aerial roots demonstrating the greatest biomass increase. Higher humidities for indoor niches, together with fertiliser applications to aerial roots will support indoor plant growth, creating lush calming indoor environments for people inhabitants.
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Affiliation(s)
- Laura Sheeran
- Division of Agriculture and Environmental Science, School of Biosciences, The University of Nottingham, Sutton Bonington, UK
| | - Amanda Rasmussen
- Division of Agriculture and Environmental Science, School of Biosciences, The University of Nottingham, Sutton Bonington, UK
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13
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Scafaro AP, Posch BC, Evans JR, Farquhar GD, Atkin OK. Rubisco deactivation and chloroplast electron transport rates co-limit photosynthesis above optimal leaf temperature in terrestrial plants. Nat Commun 2023; 14:2820. [PMID: 37198175 DOI: 10.1038/s41467-023-38496-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 05/03/2023] [Indexed: 05/19/2023] Open
Abstract
Net photosynthetic CO2 assimilation rate (An) decreases at leaf temperatures above a relatively mild optimum (Topt) in most higher plants. This decline is often attributed to reduced CO2 conductance, increased CO2 loss from photorespiration and respiration, reduced chloroplast electron transport rate (J), or deactivation of Ribulose-1,5-bisphosphate Carboxylase Oxygenase (Rubisco). However, it is unclear which of these factors can best predict species independent declines in An at high temperature. We show that independent of species, and on a global scale, the observed decline in An with rising temperatures can be effectively accounted for by Rubisco deactivation and declines in J. Our finding that An declines with Rubisco deactivation and J supports a coordinated down-regulation of Rubisco and chloroplast electron transport rates to heat stress. We provide a model that, in the absence of CO2 supply limitations, can predict the response of photosynthesis to short-term increases in leaf temperature.
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Affiliation(s)
- Andrew P Scafaro
- Division of Plant Sciences, Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia.
- Centre for Entrepreneurial Agri-Technology, Gould Building, Australian National University, Canberra, 2601, Australia.
| | - Bradley C Posch
- Department of Research, Collections and Conservation, Desert Botanical Garden, Phoenix, AZ, USA
| | - John R Evans
- Division of Plant Sciences, Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia
| | - Graham D Farquhar
- Division of Plant Sciences, Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia
| | - Owen K Atkin
- Division of Plant Sciences, Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia
- Centre for Entrepreneurial Agri-Technology, Gould Building, Australian National University, Canberra, 2601, Australia
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14
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Zhang M, Li H, Zhang L, Liu J. Heat stress, especially when coupled with high light, accelerates the decline of tropical seagrass (Enhalus acoroides) meadows. MARINE POLLUTION BULLETIN 2023; 192:115043. [PMID: 37201350 DOI: 10.1016/j.marpolbul.2023.115043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 03/23/2023] [Accepted: 05/06/2023] [Indexed: 05/20/2023]
Abstract
Heat stress threatens the survival of seagrass, but its damage mechanisms are unclear. In this study, the results reveal that heat stress exceeding 36 °C in the dark caused inactivation of the PSII reaction center, damaging both the PSII donor and acceptor sides in Enhalus acoroides. High light further increased the damage to the photosynthetic apparatus under heat stress. The stronger the heat stress under high light, the harder the recovery of photosynthetic activity. Therefore, during ebb tide at noon in nature, heat stress combined with strong light would induce a significant, even irreversible decrease in photosynthetic activity. Moreover, the heat stress hindered the transcription of psbA and RuBisCO, enhanced respiratory O2, and induced severe peroxidation even if the SOD, APX, and GPX activities significantly improved. The results clearly suggest that heat stress, especially when coupled with high light, may be an important cause for the decline of E. acoroides meadows.
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Affiliation(s)
- Mengjie Zhang
- CAS and Shandong Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China
| | - Hu Li
- CAS and Shandong Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China
| | - Litao Zhang
- CAS and Shandong Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, 1 Wenhai Road, Aoshanwei Town, Jimo, Qingdao 266237, China
| | - Jianguo Liu
- CAS and Shandong Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, 1 Wenhai Road, Aoshanwei Town, Jimo, Qingdao 266237, China.
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15
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Xu L, Zhao H, Wang J, Wang X, Jia X, Wang L, Xu Z, Li R, Jiang K, Chen Z, Luo J, Xie X, Yi K. AIM1-dependent high basal salicylic acid accumulation modulates stomatal aperture in rice. THE NEW PHYTOLOGIST 2023; 238:1420-1430. [PMID: 36843251 DOI: 10.1111/nph.18842] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 02/18/2023] [Indexed: 06/18/2023]
Abstract
The basal levels of salicylic acid (SA) vary dramatically among plant species. In the shoot, for example, rice contains almost 100 times higher SA levels than Arabidopsis. Despite its high basal levels, neither the biosynthetic pathway nor the biological functions of SA are well understood in rice. Combining with metabolite analysis, physiological, and genetic approaches, we found that the synthesis of basal SA in rice shoot is dependent on OsAIM1, which encodes a beta-oxidation enzyme in the phenylalanine ammonia-lyase (PAL) pathway. Compromised SA accumulation in the Osaim1 mutant led to a lower shoot temperature than wild-type plants. However, this shoot temperature defect resulted from increased transpiration due to elevated steady-state stomatal aperture in the mutant. Furthermore, the high basal SA level is required for sustained expression of OsWRKY45 to modulate the steady-state stomatal aperture and shoot temperature in rice. Taken together, these results provide the direct genetic evidence for the critical role of the PAL pathway in the biosynthesis of high basal level SA in rice, which plays an important role in the regulation of steady-state stomatal aperture to promote fitness under stress conditions.
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Affiliation(s)
- Lei Xu
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Hongyu Zhao
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Junbin Wang
- International Joint Center for the Mechanismic Dissection and Genetic Improvement of Crop Stress Tolerance, College of Agriculture & Resources and Environmental Sciences, Tianjin Agricultural University, Tianjin, 300392, China
- College of Basic Sciences, Tianjin Agricultural University, Tianjin, 300392, China
| | - Xuming Wang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ministry of Agriculture Key Laboratory for Plant Protection and Biotechnology, Zhejiang Provincial Key Laboratory of Plant Virology, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Xianqing Jia
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Long Wang
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Zhuang Xu
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Ruili Li
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Kun Jiang
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, 310058, China
- College of Life Sciences, China Jiliang University, 258 Xueyuan Street, Hangzhou, Zhejiang, 310018, China
| | - Zhixiang Chen
- Purdue Center for Plant Biology, Department of Botany and Plant Pathology, Purdue University, 915 W. State Street, West Lafayette, IN, 47907-2054, USA
| | - Jie Luo
- Sanya Nanfan Research Institute of Hainan University, Hainan Yazhou Bay Seed Laboratory, Sanya, 572025, China
| | - Xiaodong Xie
- International Joint Center for the Mechanismic Dissection and Genetic Improvement of Crop Stress Tolerance, College of Agriculture & Resources and Environmental Sciences, Tianjin Agricultural University, Tianjin, 300392, China
| | - Keke Yi
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
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16
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Wang J, Xu J, Wang L, Zhou M, Nian J, Chen M, Lu X, Liu X, Wang Z, Cen J, Liu Y, Zhang Z, Zeng D, Hu J, Zhu L, Dong G, Ren D, Gao Z, Shen L, Zhang Q, Li Q, Guo L, Yu S, Qian Q, Zhang G. SEMI-ROLLED LEAF 10 stabilizes catalase isozyme B to regulate leaf morphology and thermotolerance in rice (Oryza sativa L.). PLANT BIOTECHNOLOGY JOURNAL 2023; 21:819-838. [PMID: 36597711 PMCID: PMC10037157 DOI: 10.1111/pbi.13999] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 12/18/2022] [Accepted: 12/25/2022] [Indexed: 06/17/2023]
Abstract
Plant architecture and stress tolerance play important roles in rice breeding. Specific leaf morphologies and ideal plant architecture can effectively improve both abiotic stress resistance and rice grain yield. However, the mechanism by which plants simultaneously regulate leaf morphogenesis and stress resistance remains elusive. Here, we report that SRL10, which encodes a double-stranded RNA-binding protein, regulates leaf morphology and thermotolerance in rice through alteration of microRNA biogenesis. The srl10 mutant had a semi-rolled leaf phenotype and elevated sensitivity to high temperature. SRL10 directly interacted with catalase isozyme B (CATB), and the two proteins mutually increased one other's stability to enhance hydrogen peroxide (H2 O2 ) scavenging, thereby contributing to thermotolerance. The natural Hap3 (AGC) type of SRL10 allele was found to be present in the majority of aus rice accessions, and was identified as a thermotolerant allele under high temperature stress in both the field and the growth chamber. Moreover, the seed-setting rate was 3.19 times higher and grain yield per plant was 1.68 times higher in near-isogenic line (NIL) carrying Hap3 allele compared to plants carrying Hap1 allele under heat stress. Collectively, these results reveal a new locus of interest and define a novel SRL10-CATB based regulatory mechanism for developing cultivars with high temperature tolerance and stable yield. Furthermore, our findings provide a theoretical basis for simultaneous breeding for plant architecture and stress resistance.
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Affiliation(s)
- Jiajia Wang
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene ResearchCollege of Plant Science and Technology, Huazhong Agricultural UniversityWuhanChina
| | - Jing Xu
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding of Zhejiang ProvinceResearch Institute of Subtropical Forestry, Chinese Academy of ForestryHangzhouChina
| | - Li Wang
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Mengyu Zhou
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Jinqiang Nian
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Minmin Chen
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Xueli Lu
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Xiong Liu
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Zian Wang
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Jiangsu Cen
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Yiting Liu
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Zhihai Zhang
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Dali Zeng
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Jiang Hu
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Li Zhu
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Guojun Dong
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Deyong Ren
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Zhenyu Gao
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Lan Shen
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Qiang Zhang
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Qing Li
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Longbiao Guo
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
| | - Sibin Yu
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene ResearchCollege of Plant Science and Technology, Huazhong Agricultural UniversityWuhanChina
| | - Qian Qian
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
- Hainan Yazhou Bay Seed LaboratorySanyaChina
- National Nanfan Research Institute (Sanya), Chinese Academy of Agricultural SciencesSanyaChina
| | - Guangheng Zhang
- State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina
- Hainan Yazhou Bay Seed LaboratorySanyaChina
- National Nanfan Research Institute (Sanya), Chinese Academy of Agricultural SciencesSanyaChina
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17
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Gong XW, Hao GY. The synergistic effect of hydraulic and thermal impairments accounts for the severe crown damage in Fraxinus mandshurica seedlings following the combined drought-heatwave stress. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 856:159017. [PMID: 36167124 DOI: 10.1016/j.scitotenv.2022.159017] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Revised: 09/20/2022] [Accepted: 09/20/2022] [Indexed: 06/16/2023]
Abstract
Drought combined with extreme heatwaves has been increasingly identified as the important trigger of worldwide tree mortality in the context of climate change; nonetheless, our understanding of the potential hydraulic and thermal impairments of hot droughts to trees and the subsequent post-recovery process remains limited. To investigate the response of tree water and carbon relations to drought, heatwave, and combined drought-heatwave stresses, three-year-old potted seedlings of Fraxinus mandshurica Rupr., a dominant tree species in temperate forests of northeast China, were grown under well-watered and drought-stressed conditions and exposed to a rapid, acute heatwave treatment. During the heatwave treatment with a maximum temperature exceeding 40 °C for two days, the leaf temperature of drought-stressed seedlings was, on average, 5 °C higher than that of well-watered counterparts due to less effective evaporative cooling, indicating that soil water availability influenced leaf thermoregulatory capacity during hot extremes. Consistently, more pronounced crown damage, as shown by 13 % irreversible leaf scorch, was found in seedlings under the drought-heatwave treatment relative to sole heatwave treatment, alongside the more severe stem xylem embolism and leaf electrolyte leakage. While the heatwave treatment accelerated the depletion of non-structural carbohydrates in drought-stressed seedlings, the increase of branch soluble sugar concentration in response to heatwave might be related to the requirement for maintaining hydraulic functioning via osmoregulation under high dehydration risk. The coordination between leaf stomatal conductance and total non-structural carbohydrate content during the post-heatwave recovery phase implied that plant-water relations and carbon physiology were closely coupled in coping with hot droughts. This study highlights that, under scenarios of aggravating drought co-occurring with heatwaves, tree seedlings could face a high risk of crown decline in relation to the synergistically increased hydraulic and thermal impairments.
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Affiliation(s)
- Xue-Wei Gong
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China; Key Laboratory of Terrestrial Ecosystem Carbon Neutrality, Liaoning Province, Shenyang 110016, China; Qingyuan Forest CERN, National Observation and Research Station, Liaoning Province, Shenyang 110016, China
| | - Guang-You Hao
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China; Key Laboratory of Terrestrial Ecosystem Carbon Neutrality, Liaoning Province, Shenyang 110016, China; Qingyuan Forest CERN, National Observation and Research Station, Liaoning Province, Shenyang 110016, China.
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18
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Kullberg AT, Feeley KJ. Limited acclimation of leaf traits and leaf temperatures in a subtropical urban heat island. TREE PHYSIOLOGY 2022; 42:2266-2281. [PMID: 35708568 DOI: 10.1093/treephys/tpac066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 06/11/2022] [Indexed: 06/15/2023]
Abstract
The consequences of rising temperatures for trees will vary between species based on their abilities to acclimate their leaf thermoregulatory traits and photosynthetic thermal tolerances. We tested the hypotheses that adult trees in warmer growing conditions (i) acclimate their thermoregulatory traits to regulate leaf temperatures, (ii) acclimate their thermal tolerances such that tolerances are positively correlated with leaf temperature and (iii) that species with broader thermal niche breadths have greater acclimatory abilities. To test these hypotheses, we measured leaf traits and thermal tolerances of seven focal tree species across steep thermal gradients in Miami's urban heat island. We found that some functional traits varied significantly across air temperatures within species. For example, leaf thickness increased with maximum air temperature in three species, and leaf mass per area and leaf reflectance both increased with air temperature in one species. Only one species was marginally more homeothermic than expected by chance due to acclimation of its thermoregulatory traits, but this acclimation was insufficient to offset elevated air temperatures. Thermal tolerances acclimated to higher maximum air temperatures in two species. As a result of limited acclimation, leaf thermal safety margins (TSMs) were narrower for trees in hotter areas. We found some support for our hypothesis that species with broader thermal niches are better at acclimating to maintain more stable TSMs across the temperature gradients. These findings suggest that trees have limited abilities to acclimate to high temperatures and that thermal niche specialists may be at a heightened risk of thermal stress as global temperatures continue to rise.
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Affiliation(s)
- Alyssa T Kullberg
- Department of Biology, University of Miami, Coral Gables, FL 33146, USA
| | - Kenneth J Feeley
- Department of Biology, University of Miami, Coral Gables, FL 33146, USA
- Fairchild Tropical Botanic Garden, Coral Gables, FL 33156, USA
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19
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Feng X, Zhong L, Tian Q, Zhao W. Leaf water potential-dependent leaflet closure contributes to legume leaves cool down and drought avoidance under diurnal drought stress. TREE PHYSIOLOGY 2022; 42:2239-2251. [PMID: 35939343 DOI: 10.1093/treephys/tpac075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 07/02/2022] [Indexed: 06/15/2023]
Abstract
Efficient thermoregulation under diurnal drought stress protects leaves from photosystem damage and water supply-demand imbalance, yet the cool effect and drought avoidance by leaflet closure have not been well understood. We investigated the cool effect and the drought avoidance of leaflet closure in legume species that survived in the semi-arid region facing seasonal and diurnal drought stress. The results showed that leaflet closure effectively cooled down legume leaves through a reduction of projected leaflet area and the cosine of the angle of incidence (cos i). The leaflet closure was strongly dependent on leaf water potential (Ψleaf). In addition, by characterizing the sequence of key leaf drought response traits, we found leaflet closure occurred after stomatal closure and reduced transpiration rate but before hydraulic failure and turgor loss point (Ψtlp). The meta-analysis also showed that the leaflet closure and cos i decreased after the stomatal conductance declined but before midday. These results imply that Ψleaf-dependent leaflet closure as an alternative to transpiration for leaflet cooling down and as a protective drought avoidance strategy assisting sessile legume plants survival under drought stress.
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Affiliation(s)
- Xiangyan Feng
- Linze Inland River Basin Research Station, Key Laboratory of Ecohydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
- University of Chinese Academy of Sciences, Beijing 100029, China
| | - Lingfei Zhong
- College of Geography and Environment Science, Northwest Normal University, Lanzhou 730070, China
| | - Quanyan Tian
- Linze Inland River Basin Research Station, Key Laboratory of Ecohydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Wenzhi Zhao
- Linze Inland River Basin Research Station, Key Laboratory of Ecohydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
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20
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Li X, Wen Y, Chen X, Qie Y, Cao KF, Wee AKS. Correlations between photosynthetic heat tolerance and leaf anatomy and climatic niche in Asian mangrove trees. PLANT BIOLOGY (STUTTGART, GERMANY) 2022; 24:960-966. [PMID: 35962602 DOI: 10.1111/plb.13460] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 07/18/2022] [Indexed: 06/15/2023]
Abstract
Photosynthetic heat tolerance (PHT ) is a key predictor of plant response to climate change. Mangroves are an ecologically and economically important coastal plant community comprised of trees growing at their physiological limits. Mangroves are currently impacted by global warming, yet the PHT of mangrove trees is poorly understood. In this study, we provide the first assessment of PHT in 13 Asian mangrove species, based on the critical temperature that causes the initial damage (TCrit ) and the temperature that causes 50% damage (T50 ) to photosystem II. We tested the hypotheses that the PHT in mangroves is: (i) correlated with climatic niche and leaf traits, and (ii) higher than in plants from other tropical ecosystems. Our results demonstrated correlations between PHT and multiple key climate variables, the palisade to spongy mesophyll ratio and the leaf area. The two most heat-sensitive species were Kandelia obovata and Avicennia marina. Our study also revealed that mangrove trees show high heat tolerance compared to plants from other tropical ecosystems. The high PHT of mangroves thus demonstrated a conservative evolutionary strategy in heat tolerance, and highlights the need for integrative and comparative studies on thermoregulatory traits and climatic niche in order to understand the physiological response of mangrove trees to climate change-driven heatwaves and rising global temperatures.
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Affiliation(s)
- X Li
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, China
| | - Y Wen
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - X Chen
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, China
| | - Y Qie
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, China
| | - K-F Cao
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, China
| | - A K S Wee
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, China
- School of Environmental and Geographical Sciences, University of Nottingham Malaysia, Jalan Broga, Semenyih, Malaysia
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21
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No evidence of canopy-scale leaf thermoregulation to cool leaves below air temperature across a range of forest ecosystems. Proc Natl Acad Sci U S A 2022; 119:e2205682119. [PMID: 36095211 PMCID: PMC9499539 DOI: 10.1073/pnas.2205682119] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Understanding and predicting the relationship between leaf temperature (Tleaf) and air temperature (Tair) is essential for projecting responses to a warming climate, as studies suggest that many forests are near thermal thresholds for carbon uptake. Based on leaf measurements, the limited leaf homeothermy hypothesis argues that daytime Tleaf is maintained near photosynthetic temperature optima and below damaging temperature thresholds. Specifically, leaves should cool below Tair at higher temperatures (i.e., > ∼25-30°C) leading to slopes <1 in Tleaf/Tair relationships and substantial carbon uptake when leaves are cooler than air. This hypothesis implies that climate warming will be mitigated by a compensatory leaf cooling response. A key uncertainty is understanding whether such thermoregulatory behavior occurs in natural forest canopies. We present an unprecedented set of growing season canopy-level leaf temperature (Tcan) data measured with thermal imaging at multiple well-instrumented forest sites in North and Central America. Our data do not support the limited homeothermy hypothesis: canopy leaves are warmer than air during most of the day and only cool below air in mid to late afternoon, leading to Tcan/Tair slopes >1 and hysteretic behavior. We find that the majority of ecosystem photosynthesis occurs when canopy leaves are warmer than air. Using energy balance and physiological modeling, we show that key leaf traits influence leaf-air coupling and ultimately the Tcan/Tair relationship. Canopy structure also plays an important role in Tcan dynamics. Future climate warming is likely to lead to even greater Tcan, with attendant impacts on forest carbon cycling and mortality risk.
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22
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Transpirational Leaf Cooling Effect Did Not Contribute Equally to Biomass Retention in Wheat Genotypes under High Temperature. PLANTS 2022; 11:plants11162174. [PMID: 36015478 PMCID: PMC9416376 DOI: 10.3390/plants11162174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 08/16/2022] [Accepted: 08/18/2022] [Indexed: 12/02/2022]
Abstract
High temperature and water deficit are the most critical yield-limiting environmental factors for wheat in rainfed environments. It is important to understand the heat avoidance mechanisms and their associations with leaf morpho-physiological traits that allow crops to stay cool and retain high biomass under warm and dry conditions. We examined 20 morpho-physiologically diverse wheat genotypes under ambient and elevated temperatures (Tair) to investigate whether increased water use leads to high biomass retention due to increased leaf cooling. An experiment was conducted under well-watered conditions in two partially controlled glasshouses. We measured plant transpiration (Tr), leaf temperature (Tleaf), vapor pressure deficit (VPD), and associated leaf morpho-physiological characteristics. High water use and leaf cooling increased biomass retention under high temperatures, but increased use did not always increase biomass retention. Some genotypes maintained biomass, irrespective of water use, possibly through mechanisms other than leaf cooling, indicating their adaptation under water shortage. Genotypic differences in leaf cooling capacity did not always correlate with Tr (VPD) response. In summary, the contribution of high water use or the leaf cooling effect on biomass retention under high temperature is genotype-dependent and possibly due to variations in leaf morpho-physiological traits. These findings are useful for breeding programs to develop climate resilient wheat cultivars.
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23
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Xi L, Zhang M, Zhang L, Lew TTS, Lam YM. Novel Materials for Urban Farming. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2105009. [PMID: 34668260 DOI: 10.1002/adma.202105009] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/31/2021] [Indexed: 05/27/2023]
Abstract
Scarcity of natural resources, shifting demographics, climate change, and increasing waste are four major challenges in the quest to feed the exploding world population. These challenges serve as the impetus to harness novel technologies to improve agriculture, productivity, and sustainability. Urban farming has several advantages over conventional farming: higher productivity, improved sustainability, and the ability to provide fresh food all year round. Novel materials are key to accelerating the evolution of urban farming - with their ability to facilitate controlled release of nutrients and pesticides, improved seed health, substrates with better water retention capability, more efficient recycling of agricultural waste, and precise plant health monitoring. Materials science enables environmental sustainability and higher harvest yields in urban farms. Here, Singapore is used as an example of a land-scarce city where urban farming may be the solution for future food production. Potential research directions and challenges in urban farming are highlighted, and how material optimization and innovation drive the development of urban farming to meet national and global food demands is briefly discussed. This review serves as a guide for researchers and a reference for stakeholders of urban farms, policy makers, and other interested parties.
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Affiliation(s)
- Lifei Xi
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
- Facility for Analysis, Characterisation, Testing and Simulation (FACTS), Nanyang Technological University, Singapore, 639798, Singapore
| | - Mengyuan Zhang
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Liling Zhang
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Tedrick T S Lew
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR), Singapore, 138634, Singapore
- Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore, 117585, Singapore
| | - Yeng Ming Lam
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
- Facility for Analysis, Characterisation, Testing and Simulation (FACTS), Nanyang Technological University, Singapore, 639798, Singapore
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24
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Dong J, Yin T, Liu H, Sun L, Qin S, Zhang Y, Liu X, Fan P, Wang H, Zheng P, Wang R. Vegetation Greenness Dynamics in the Western Greater Khingan Range of Northeast China Based on Dendrochronology. BIOLOGY 2022; 11:biology11050679. [PMID: 35625407 PMCID: PMC9138829 DOI: 10.3390/biology11050679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 04/26/2022] [Accepted: 04/26/2022] [Indexed: 11/16/2022]
Abstract
Understanding the vegetation greenness dynamics in the forest–steppe transition zone is essential for ecosystem management, and in order to study ecological changes in the region. This study provides a valuable record of the vegetation greenness dynamics in the western Greater Khingan Range over the past 193 years (1826–2018) based on tree-ring data represented by the normalized difference vegetation index (NDVI). The reconstructed vegetation greenness dynamics record contains a total of 32 years of high vegetation greenness and 37 years of low vegetation greenness, together occupying 35.8% of the entire reconstructed period (193 years). Climate (precipitation) is the main influence on the vegetation greenness dynamics at this site, but human activities have also had a significant impact over the last few decades. The magnitude, frequency, and duration of extreme changes in vegetation greenness dynamics have increased significantly, with progressively shorter intervals. Analyses targeting human behavior have shown that the density of livestock, agricultural land area, and total population have gradually increased, encroaching on forests and grasslands and reducing the inter-annual variability. After 2002, the government implemented projects to return farmland to its original ecosystems, and for the implementation of new land management practices (which are more ecologically related); as such, the vegetation conditions began to improve. These findings will help us to understand the relationship between climate change and inter- and intra- annual dynamics in northeastern China, and to better understand the impact of human activities on vegetation greenness dynamics.
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Affiliation(s)
- Jibin Dong
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao 266237, China; (J.D.); (T.Y.); (H.L.); (L.S.); (S.Q.); (Y.Z.); (X.L.); (H.W.); (R.W.)
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao 266237, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Qingdao 266237, China;
| | - Tingting Yin
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao 266237, China; (J.D.); (T.Y.); (H.L.); (L.S.); (S.Q.); (Y.Z.); (X.L.); (H.W.); (R.W.)
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao 266237, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Qingdao 266237, China;
| | - Hongxiang Liu
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao 266237, China; (J.D.); (T.Y.); (H.L.); (L.S.); (S.Q.); (Y.Z.); (X.L.); (H.W.); (R.W.)
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao 266237, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Qingdao 266237, China;
| | - Lu Sun
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao 266237, China; (J.D.); (T.Y.); (H.L.); (L.S.); (S.Q.); (Y.Z.); (X.L.); (H.W.); (R.W.)
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao 266237, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Qingdao 266237, China;
| | - Siqi Qin
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao 266237, China; (J.D.); (T.Y.); (H.L.); (L.S.); (S.Q.); (Y.Z.); (X.L.); (H.W.); (R.W.)
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao 266237, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Qingdao 266237, China;
| | - Yang Zhang
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao 266237, China; (J.D.); (T.Y.); (H.L.); (L.S.); (S.Q.); (Y.Z.); (X.L.); (H.W.); (R.W.)
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao 266237, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Qingdao 266237, China;
| | - Xiao Liu
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao 266237, China; (J.D.); (T.Y.); (H.L.); (L.S.); (S.Q.); (Y.Z.); (X.L.); (H.W.); (R.W.)
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao 266237, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Qingdao 266237, China;
| | - Peixian Fan
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Qingdao 266237, China;
| | - Hui Wang
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao 266237, China; (J.D.); (T.Y.); (H.L.); (L.S.); (S.Q.); (Y.Z.); (X.L.); (H.W.); (R.W.)
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao 266237, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Qingdao 266237, China;
| | - Peiming Zheng
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao 266237, China; (J.D.); (T.Y.); (H.L.); (L.S.); (S.Q.); (Y.Z.); (X.L.); (H.W.); (R.W.)
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao 266237, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Qingdao 266237, China;
- Correspondence:
| | - Renqing Wang
- Institute of Ecology and Biodiversity, School of Life Sciences, Shandong University, Qingdao 266237, China; (J.D.); (T.Y.); (H.L.); (L.S.); (S.Q.); (Y.Z.); (X.L.); (H.W.); (R.W.)
- Shandong Provincial Engineering and Technology Research Center for Vegetation Ecology, Shandong University, Qingdao 266237, China
- Qingdao Forest Ecology Research Station of National Forestry and Grassland Administration, Qingdao 266237, China;
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Abstract
Drought is one of the major abiotic constraints on wheat yields and also for sustainability of production levels around the world. In the near future, the occurrence likelihood of droughts is predicted to become more common, due to changing climatic conditions, thereby posing a serious threat to the food security system. Heterogeneity, in its time of occurrence and severity levels, is likely to further augment the complexity of drought conditions. Although wheat crop growth has progressively risen to good levels, as evident by notable increases in both area and production, the expected wheat demand for the ever-growing population is quite high. Besides crop yield volatility in the era of climate change and dwindling resources, “trait-based” breeding programs are required, so as to develop high yielding, climate resilient and stable genotypes, at a faster pace. For this to happen, a broad genetic base and wider adaptability to suit varied agro-ecologies would provide enough scope for their quicker spread. The current review places emphasis on making distinct categories of the wheat cultivars/advanced breeding lines, as tolerant, moderately tolerant or susceptible to drought stresses, duly supported by an extensive up-to-date literature base and will be useful for wheat researchers, in order to choose the best potential donors as parents, coupled with the associated traits for the development of drought-tolerant wheat varieties, and also to facilitate molecular studies.
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Kitudom N, Fauset S, Zhou Y, Fan Z, Li M, He M, Zhang S, Xu K, Lin H. Thermal safety margins of plant leaves across biomes under a heatwave. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:150416. [PMID: 34852425 DOI: 10.1016/j.scitotenv.2021.150416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 09/13/2021] [Accepted: 09/14/2021] [Indexed: 06/13/2023]
Abstract
Climate change has great impacts on forest ecosystems, especially with the increasing frequency of heatwaves. Thermal safety margin (TSM) calculated by the difference between body temperature and thermotolerance threshold is useful to predict thermal safety of organisms. It has been widely used for animals, whereas has rarely been reported for plants. Besides, most of the previous studies used only thermotolerance to estimate thermal safety or used thermotolerance and air temperature (Ta) to calculate TSM. However, leaf temperature (Tl) is the real "body" temperature of plant leaves. Tl decoupling from Ta might induce large error in TSM. Here, we investigated TSM of photosystem II (thermotolerance of PSII - the maximum Tl) of dominant canopy plants in four forests from tropical to temperate biomes during a heatwave, and compared the TSMs calculated by Tl (TSM.Tl) and Ta (TSM.Ta) respectively. Also, thermal related leaf traits were investigated. The results showed that both TSM. Tl and TSM.Ta decreased from the cool forests to the hot forests. TSM.Tl was highly correlated with the maximum leaf temperature (Tlmax), while had an opposite trend with thermotolerance across biomes. Thus, Tlmax instead of thermotolerance can be used to evaluate TSM. The maximum Ta (Tamax), Tlmax and leaf traits explained 68% of the variance of thermotolerance in a random forest model, where Tamax and Tlmax explained 62%. TSM.Ta could not distinguish thermal safety differences between co-occurring species. The overestimation of TSM by TSM.Ta increased from the tropical to the temperate forest, and increased with Tl within biome. Therefore, it is not recommended to use TSM.Ta in cold forests. The present study enriches the dataset of photosynthetic TSMs across biomes, proposes using Tlmax to estimate TSMs of leaves, and highlights the risk of hot dry forest during heatwaves.
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Affiliation(s)
- Nawatbhrist Kitudom
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Sophie Fauset
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China; School of Geography, Earth and Environmental Sciences, University of Plymouth, Plymouth, UK
| | - Yingying Zhou
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zexin Fan
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China; Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Xishuangbanna 666303, China; Ailaoshan Station of Subtropical Forest Ecosystem Studies, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Jingdong, Yunnan 676209, China
| | - Murong Li
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China; College of Biology and Chemistry, Puer University, Puer, Yunnan 665000, China
| | - Mingjian He
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China; College of Biology and Chemistry, Puer University, Puer, Yunnan 665000, China
| | - Shubin Zhang
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China
| | - Kun Xu
- Yunnan Lijiang Forest Ecosystem National Observation and Research Station, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
| | - Hua Lin
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China; Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Xishuangbanna 666303, China.
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27
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Marchin RM, Backes D, Ossola A, Leishman MR, Tjoelker MG, Ellsworth DS. Extreme heat increases stomatal conductance and drought-induced mortality risk in vulnerable plant species. GLOBAL CHANGE BIOLOGY 2022; 28:1133-1146. [PMID: 34741566 PMCID: PMC9299030 DOI: 10.1111/gcb.15976] [Citation(s) in RCA: 57] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 10/12/2021] [Accepted: 10/27/2021] [Indexed: 05/29/2023]
Abstract
Tree mortality during global-change-type drought is usually attributed to xylem dysfunction, but as climate change increases the frequency of extreme heat events, it is necessary to better understand the interactive role of heat stress. We hypothesized that some drought-stressed plants paradoxically open stomata in heatwaves to prevent leaves from critically overheating. We experimentally imposed heat (>40°C) and drought stress onto 20 broadleaf evergreen tree/shrub species in a glasshouse study. Most well-watered plants avoided lethal overheating, but drought exacerbated thermal damage during heatwaves. Thermal safety margins (TSM) quantifying the difference between leaf surface temperature and leaf critical temperature, where photosynthesis is disrupted, identified species vulnerability to heatwaves. Several mechanisms contributed to high heat tolerance and avoidance of damaging leaf temperatures-small leaf size, low leaf osmotic potential, high leaf mass per area (i.e., thick, dense leaves), high transpirational capacity, and access to water. Water-stressed plants had smaller TSM, greater crown dieback, and a fundamentally different stomatal heatwave response relative to well-watered plants. On average, well-watered plants closed stomata and decreased stomatal conductance (gs ) during the heatwave, but droughted plants did not. Plant species with low gs , either due to isohydric stomatal behavior under water deficit or inherently low transpirational capacity, opened stomata and increased gs under high temperatures. The current paradigm maintains that stomata close before hydraulic thresholds are surpassed, but our results suggest that isohydric species may dramatically increase gs (over sixfold increases) even past their leaf turgor loss point. By actively increasing water loss at high temperatures, plants can be driven toward mortality thresholds more rapidly than has been previously recognized. The inclusion of TSM and responses to heat stress could improve our ability to predict the vulnerability of different tree species to future droughts.
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Affiliation(s)
- Renée M. Marchin
- Hawkesbury Institute for the EnvironmentWestern Sydney UniversityPenrithNew South WalesAustralia
| | - Diana Backes
- Hawkesbury Institute for the EnvironmentWestern Sydney UniversityPenrithNew South WalesAustralia
| | - Alessandro Ossola
- Department of Biological SciencesMacquarie UniversityNorth RydeNew South WalesAustralia
| | - Michelle R. Leishman
- Department of Biological SciencesMacquarie UniversityNorth RydeNew South WalesAustralia
| | - Mark G. Tjoelker
- Hawkesbury Institute for the EnvironmentWestern Sydney UniversityPenrithNew South WalesAustralia
| | - David S. Ellsworth
- Hawkesbury Institute for the EnvironmentWestern Sydney UniversityPenrithNew South WalesAustralia
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28
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Rawat M, Arunachalam K, Arunachalam A, Alatalo JM, Pandey R. Assessment of leaf morphological, physiological, chemical and stoichiometry functional traits for understanding the functioning of Himalayan temperate forest ecosystem. Sci Rep 2021; 11:23807. [PMID: 34893677 PMCID: PMC8664835 DOI: 10.1038/s41598-021-03235-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 11/15/2021] [Indexed: 11/30/2022] Open
Abstract
Leaf functional traits support plant survival and growth in different stress and disturbed conditions and respond according to leaf habit. The present study examined 13 leaf traits (3 morphological, 3 chemical, 5 physiological, and 2 stoichiometry) of nine dominant forest tree species (3 coniferous, 3 deciduous broad-leaved, 3 evergreen broad-leafed) to understand the varied response of leaf habits. The hypothesis was to test if functional traits of the conifers, deciduous and evergreen differ significantly in the temperate forest and to determine the applicability of leaf economic theory i.e., conservative vs. acquisitive resource investment, in the temperate Himalayan region. The attributes of the functional traits i.e., leaf area (LA), specific leaf area (SLA), leaf dry matter content (LDMC), leaf water content (LWC), stomatal conductance (Gs), and transpiration (E) followed the order deciduous > evergreen > coniferous. Leaf carbon and leaf C/N ratio showed the opposite pattern, coniferous > evergreen > deciduous. Chlorophyll (Chl) and photosynthetic rate (A) were highest for evergreen species, followed by deciduous and coniferous species. Also, structural equation modelling determined that morphological factors were negatively related to physiological and positively with chemical factors. Nevertheless, physiological and chemical factors were positively related to each other. The physiological traits were mainly regulated by stomatal conductance (Gs) however the morphological traits were determined by LDMC. Stoichiometry traits, such as leaf C/N, were found to be positively related to leaf carbon, and leaf N/P was found to be positively related to leaf nitrogen. The result of the leaf functional traits relationship would lead to precise prediction for the functionality of the temperate forest ecosystem at the regional scale.
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Affiliation(s)
- Monika Rawat
- School of Environment and Natural Resources, Doon University, Dehradun, 248001, India. .,Indian Council of Forestry Research and Education, Dehradun, India.
| | - Kusum Arunachalam
- School of Environment and Natural Resources, Doon University, Dehradun, 248001, India
| | - Ayyandar Arunachalam
- Indian Council of Agricultural Research (ICAR), Krishi Bhawan, New Delhi, 110001, India
| | - Juha M Alatalo
- Environmental Science Center, Qatar University, Doha, Qatar
| | - Rajiv Pandey
- Indian Council of Forestry Research and Education, Dehradun, India
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Polutchko SK, Stewart JJ, Adams Iii WW, Demmig-Adams B. Photosynthesis and foliar vascular adjustments to growth light intensity in summer annual species with symplastic and apoplastic phloem loading. JOURNAL OF PLANT PHYSIOLOGY 2021; 267:153532. [PMID: 34638004 DOI: 10.1016/j.jplph.2021.153532] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 09/22/2021] [Indexed: 06/13/2023]
Abstract
Concomitant adjustments in photosynthetic capacity and size, composition, and/or density of minor foliar veins in response to growth environment were previously described primarily for winter annuals that load sugars into foliar phloem apoplastically. Here, common trends, differences associated with phloem-loading mechanism, and species-dependent differences are identified for summer annuals (loading sugars either symplastically [cucumber, pumpkin, and basil] or apoplastically [tomato and sunflower]) that were grown in low and high light. Photosynthetic capacity per leaf area was significantly positively correlated with leaf-level volume of phloem-loading cells (LCs), sugar-export conduits (sieve elements), and water conduits (tracheary elements) irrespective of phloem-loading mechanism. The relative contribution to leaf-level volume of LC numbers versus individual LC size was greater in apoplastic loaders than in symplastic loaders. Species-dependent differences included different vein density within each loading group and either greater or lower numbers of cells per minor vein (especially of tracheary elements in the symplastic loaders basil versus cucumber, respectively), which may be due to genetic adaptation to different environmental conditions. These results indicate considerable plasticity in foliar vascular features in summer annuals as well as some loading-mechanism-dependent trends.
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Affiliation(s)
- Stephanie K Polutchko
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA.
| | - Jared J Stewart
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA.
| | - William W Adams Iii
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA.
| | - Barbara Demmig-Adams
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA.
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Hein NT, Ciampitti IA, Jagadish SVK. Bottlenecks and opportunities in field-based high-throughput phenotyping for heat and drought stress. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:5102-5116. [PMID: 33474563 PMCID: PMC8272563 DOI: 10.1093/jxb/erab021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 01/18/2021] [Indexed: 05/27/2023]
Abstract
Flowering and grain-filling stages are highly sensitive to heat and drought stress exposure, leading to significant loss in crop yields. Therefore, phenotyping to enhance resilience to these abiotic stresses is critical for sustaining genetic gains in crop improvement programs. However, traditional methods for screening traits related to these stresses are slow, laborious, and often expensive. Remote sensing provides opportunities to introduce low-cost, less biased, high-throughput phenotyping methods to capture large genetic diversity to facilitate enhancement of stress resilience in crops. This review focuses on four key physiological traits and processes that are critical in understanding crop responses to drought and heat stress during reproductive and grain-filling periods. Specifically, these traits include: (i) time of day of flowering, to escape these stresses during flowering; (ii) optimizing photosynthetic efficiency; (iii) storage and translocation of water-soluble carbohydrates; and (iv) yield and yield components to provide in-season yield estimates. Moreover, we provide an overview of current advances in remote sensing in capturing these traits, and discuss the limitations with existing technology as well as future direction of research to develop high-throughput phenotyping approaches. In the future, phenotyping these complex traits will require sensor advancement, high-quality imagery combined with machine learning methods, and efforts in transdisciplinary science to foster integration across disciplines.
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Affiliation(s)
- Nathan T Hein
- Department of Agronomy, Kansas State University, Manhattan, KS, USA
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31
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Slot M, Cala D, Aranda J, Virgo A, Michaletz ST, Winter K. Leaf heat tolerance of 147 tropical forest species varies with elevation and leaf functional traits, but not with phylogeny. PLANT, CELL & ENVIRONMENT 2021; 44:2414-2427. [PMID: 33817813 DOI: 10.1111/pce.14060] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 03/29/2021] [Indexed: 06/12/2023]
Abstract
Exceeding thermal thresholds causes irreversible damage and ultimately loss of leaves. The lowland tropics are among the warmest forested biomes, but little is known about heat tolerance of tropical forest plants. We surveyed leaf heat tolerance of sun-exposed leaves from 147 tropical lowland and pre-montane forest species by determining the temperatures at which potential photosystem II efficiency based on chlorophyll a fluorescence started to decrease (TCrit ) and had decreased by 50% (T50 ). TCrit averaged 46.7°C (5th-95th percentile: 43.5°C-49.7°C) and T50 averaged 49.9°C (47.8°C-52.5°C). Heat tolerance partially adjusted to site temperature; TCrit and T50 decreased with elevation by 0.40°C and 0.26°C per 100 m, respectively, while mean annual temperature decreased by 0.63°C per 100 m. The phylogenetic signal in heat tolerance was weak, suggesting that heat tolerance is more strongly controlled by environment than by evolutionary legacies. TCrit increased with the estimated thermal time constant of the leaves, indicating that species with thermally buffered leaves maintain higher heat tolerance. Among lowland species, T50 increased with leaf mass per area, suggesting that in species with structurally more costly leaves the risk of leaf loss during hot spells is reduced. These results provide insight in variation in heat tolerance at local and regional scales.
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Affiliation(s)
- Martijn Slot
- Smithsonian Tropical Research Institute, Panama City, Republic of Panama
| | - Daniela Cala
- Smithsonian Tropical Research Institute, Panama City, Republic of Panama
- Paul H. O'Neill School of Public and Environmental Affairs, Indiana University, Bloomington, Indiana, USA
| | - Jorge Aranda
- Smithsonian Tropical Research Institute, Panama City, Republic of Panama
| | - Aurelio Virgo
- Smithsonian Tropical Research Institute, Panama City, Republic of Panama
| | - Sean T Michaletz
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Klaus Winter
- Smithsonian Tropical Research Institute, Panama City, Republic of Panama
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32
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Sadok W, Lopez JR, Smith KP. Transpiration increases under high-temperature stress: Potential mechanisms, trade-offs and prospects for crop resilience in a warming world. PLANT, CELL & ENVIRONMENT 2021; 44:2102-2116. [PMID: 33278035 DOI: 10.1111/pce.13970] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Revised: 11/19/2020] [Accepted: 11/20/2020] [Indexed: 05/24/2023]
Abstract
The frequency and intensity of high-temperature stress events are expected to increase as climate change intensifies. Concomitantly, an increase in evaporative demand, driven in part by global warming, is also taking place worldwide. Despite this, studies examining high-temperature stress impacts on plant productivity seldom consider this interaction to identify traits enhancing yield resilience towards climate change. Further, new evidence documents substantial increases in plant transpiration rate in response to high-temperature stress even under arid environments, which raise a trade-off between the need for latent cooling dictated by excessive temperatures and the need for water conservation dictated by increasing evaporative demand. However, the mechanisms behind those responses, and the potential to design the next generation of crops successfully navigating this trade-off, remain poorly investigated. Here, we review potential mechanisms underlying reported increases in transpiration rate under high-temperature stress, within the broader context of their impact on water conservation needed for crop drought tolerance. We outline three main contributors to this phenomenon, namely stomatal, cuticular and water viscosity-based mechanisms, and we outline research directions aiming at designing new varieties optimized for specific temperature and evaporative demand regimes to enhance crop productivity under a warmer and dryer climate.
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Affiliation(s)
- Walid Sadok
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, Minnesota, USA
| | - Jose R Lopez
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, Minnesota, USA
| | - Kevin P Smith
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, Minnesota, USA
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Jagadish SVK, Way DA, Sharkey TD. Plant heat stress: Concepts directing future research. PLANT, CELL & ENVIRONMENT 2021; 44:1992-2005. [PMID: 33745205 DOI: 10.1111/pce.14050] [Citation(s) in RCA: 87] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 03/10/2021] [Indexed: 05/27/2023]
Abstract
Predicted increases in future global temperatures require us to better understand the dimensions of heat stress experienced by plants. Here we highlight four key areas for improving our approach towards understanding plant heat stress responses. First, although the term 'heat stress' is broadly used, that term encompasses heat shock, heat wave and warming experiments, which vary in the duration and magnitude of temperature increase imposed. A greater integration of results and tools across these approaches is needed to better understand how heat stress associated with global warming will affect plants. Secondly, there is a growing need to associate plant responses to tissue temperatures. We review how plant energy budgets determine tissue temperature and discuss the implications of using leaf versus air temperature for heat stress studies. Third, we need to better understand how heat stress affects reproduction, particularly understudied stages such as floral meristem initiation and development. Fourth, we emphasise the need to integrate heat stress recovery into breeding programs to complement recent progress in improving plant heat stress tolerance. Taken together, we provide insights into key research gaps in plant heat stress and provide suggestions on addressing these gaps to enhance heat stress resilience in plants.
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Affiliation(s)
| | - Danielle A Way
- Department of Biology, University of Western Ontario, London, Ontario, Canada
- Nicholas School of the Environment, Duke University, Durham, North Carolina, USA
- Terrestrial Ecosystem Science & Technology Group, Environmental & Climate Sciences Department, Brookhaven National Laboratory, Upton, New York, USA
| | - Thomas D Sharkey
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
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Cowpea Ecophysiological Responses to Accumulated Water Deficiency during the Reproductive Phase in Northeastern Pará, Brazil. HORTICULTURAE 2021. [DOI: 10.3390/horticulturae7050116] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Cowpea (Vigna unguiculata (L.) Walp.) is a leguminous species widely cultivated in northern and northeastern Brazil. In the state of Pará, this crop still has low productivity due to several factors, such as low soil fertility and climatic adversity, especially the water deficiency. Therefore, the present study aimed at evaluating the physiological parameters and the productivity of cowpea plants under different water depths. The experiment was conducted in Castanhal/Pará between 2015 and 2016. A randomized block design was applied with six replications and four treatments, represented by the replacement of 100%, 50%, 25% and 0% of the water lost during crop evapotranspiration (ETc), starting from the reproductive stage. The rates of net photosynthesis (A), stomatal conductance (gs), leaf transpiration (Eleaf), substomatal CO2 concentration (Ci), leaf temperature (Tleaf) and leaf water potential (Ψw) were determined in four measurements at the R5, R7, R8 and R9 phenological stages. Cowpea was sensitive to the water availability in the soil, showing a significant difference between treatments for physiological variables and productivity. Upon reaching a Ψw equal to −0.88 MPa, the studied variables showed important changes, which allows establishing this value as a threshold for the crop regarding water stress under such experimental conditions. The different water levels in the soil directly influenced productivity for both years, indicating that the proper water supply leads to better crop growth and development, increasing productivity.
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35
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Nakai Z, Shimizu K, Oida H, Sonoda S. Host plant and humidity effects on phytoseiid mite, Gynaeseius liturivorus (Acari: Phytoseiidae) egg hatchability. EXPERIMENTAL & APPLIED ACAROLOGY 2021; 84:135-147. [PMID: 33891226 DOI: 10.1007/s10493-021-00617-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Accepted: 04/15/2021] [Indexed: 06/12/2023]
Abstract
Gynaeseius liturivorus (Ehara) (Acari: Phytoseiidae) is a promising biological control agent for tiny arthropod pests, including Thrips tabaci Lindeman (Thysanoptera: Thripidae) known as a major pest of Welsh onion. In fields during summer, G. liturivorus is observed on soybean, but not on Welsh onion, even when numerous T. tabaci are present. To elucidate G. liturivorus's occurrence on soybean and Welsh onion in relation to relative humidity (RH), we examined its egg hatching on their seedlings under low RH conditions. Then we estimated the moisture transpiration from both plants. Egg hatching occurred only on soybean plants exhibiting greater moisture transpiration. Aiming at utilizing G. liturivorus as a biological control agent for Welsh onion production in summer, evaluation of its relative tolerance and compensation potential for drought injury is necessary. Therefore, we used five phytoseiid species including G. liturivorus and Neoseiulus californicus to estimate the RH and vapor pressure deficit (VPD) at which 50% of eggs hatch (RH50 and VPD50). Furthermore, we examined G. liturivorus and N. californicus egg hatching under different RH oscillation conditions. Results show G. liturivorus as the most drought-sensitive among the five species tested, but G. liturivorus is able to compensate for lethal low-RH effects on egg hatching in part by periodic exposure to high RH conditions, as observed for N. californicus.
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Affiliation(s)
- Zenta Nakai
- Chiba Prefectural Agriculture and Forestry Research Center, 180-1 Okanezawa-cho, Midori-ku, Chiba, 266-0014, Japan.
- Chiba Prefecture Sanbu Agriculture Office, 1-11 Higashi-shinshuku, Togane, Chiba, 283-0006, Japan.
- United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Fuchu, Tokyo, 183-8509, Japan.
| | - Ken Shimizu
- Chiba Prefectural Agriculture and Forestry Research Center, 180-1 Okanezawa-cho, Midori-ku, Chiba, 266-0014, Japan
| | - Hiroshi Oida
- Chiba Prefectural Agriculture and Forestry Research Center, 180-1 Okanezawa-cho, Midori-ku, Chiba, 266-0014, Japan
- Faculty of Bioscience and Applied Chemistry, Hosei University, 3-7-2 Kajino-cho, Koganei, Tokyo, 184-8584, Japan
| | - Shoji Sonoda
- School of Agriculture, Utsunomiya University, Utsunomiya, Tochigi, 321-8505, Japan
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36
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Water-Stressed Plants Do Not Cool: Leaf Surface Temperature of Living Wall Plants under Drought Stress. SUSTAINABILITY 2021. [DOI: 10.3390/su13073910] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Urban green infrastructures offer thermal regulation to mitigate urban heat island effects. To gain a better understanding of the cooling ability of transpiring plants at the leaf level, we developed a method to measure the time series of thermal data with a miniaturized, uncalibrated thermal infrared camera. We examined the canopy temperature of four characteristic living wall plants (Heuchera x cultorum, Bergenia cordifolia, Geranium sanguineum, and Brunnera macrophylla) under increasing drought stress and compared them with a well-watered control group. The method proved suitable to evaluate differences in canopy temperature between the different treatments. Leaf temperatures of water-stressed plants were 6 to 8 °C higher than those well-watered, with differences among species. In order to cool through transpiration, vegetation in green infrastructures must be sufficiently supplied with water. Thermal cameras were found to be useful to monitor vertical greening because leaf surface temperature is closely related to drought stress. The usage of thermal cameras mounted on unmanned aerial vehicles could be a rapid and easy monitoring system to cover large façades.
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Vescio R, Abenavoli MR, Araniti F, Musarella CM, Sofo A, Laface VLA, Spampinato G, Sorgonà A. The Assessment and the Within-Plant Variation of the Morpho-Physiological Traits and VOCs Profile in Endemic and Rare Salvia ceratophylloides Ard. (Lamiaceae). PLANTS (BASEL, SWITZERLAND) 2021; 10:474. [PMID: 33802380 PMCID: PMC7998927 DOI: 10.3390/plants10030474] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Revised: 02/23/2021] [Accepted: 02/26/2021] [Indexed: 06/12/2023]
Abstract
Salvia ceratophylloides (Ard.) is an endemic and rare plant species recently rediscovered as very few individuals at two different Southern Italy sites. The study of within-plant variation is fundamental to understand the plant adaptation to the local conditions, especially in rare species, and consequently to preserve plant biodiversity. Here, we reported the variation of the morpho-ecophysiological and metabolic traits between the sessile and petiolate leaf of S. ceratophylloides plants at two different sites for understanding the adaptation strategies for surviving in these habitats. The S. ceratophylloides individuals exhibited different net photosynthetic rate, maximum quantum yield, light intensity for the saturation of the photosynthetic machinery, stomatal conductance, transpiration rate, leaf area, fractal dimension, and some volatile organic compounds (VOCs) between the different leaf types. This within-plant morpho-physiological and metabolic variation was dependent on the site. These results provide empirical evidence of sharply within-plant variation of the morpho-physiological traits and VOCs profiles in S. ceratophylloides, explaining the adaptation to the local conditions.
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Affiliation(s)
- Rosa Vescio
- Department of Agricultural Sciences, “Mediterranea” University of Reggio Calabria, Feo di Vito, 89124 Reggio Calabria, Italy; (R.V.); (M.R.A.); (C.M.M.); (V.L.A.L.); (G.S.)
| | - Maria Rosa Abenavoli
- Department of Agricultural Sciences, “Mediterranea” University of Reggio Calabria, Feo di Vito, 89124 Reggio Calabria, Italy; (R.V.); (M.R.A.); (C.M.M.); (V.L.A.L.); (G.S.)
| | - Fabrizio Araniti
- Department of Agricultural and Environmental Sciences—Production, Landscape, Agroenergy, Università Degli Studi di Milano, Via G. Celoria 2, 20133 Milan, Italy;
| | - Carmelo Maria Musarella
- Department of Agricultural Sciences, “Mediterranea” University of Reggio Calabria, Feo di Vito, 89124 Reggio Calabria, Italy; (R.V.); (M.R.A.); (C.M.M.); (V.L.A.L.); (G.S.)
| | - Adriano Sofo
- Department of European and Mediterranean Cultures, Architecture, Environment, Cultural Heritage (DiCEM), University of Basilicata, Via Lanera 20, 75100 Matera, Italy;
| | - Valentina Lucia Astrid Laface
- Department of Agricultural Sciences, “Mediterranea” University of Reggio Calabria, Feo di Vito, 89124 Reggio Calabria, Italy; (R.V.); (M.R.A.); (C.M.M.); (V.L.A.L.); (G.S.)
| | - Giovanni Spampinato
- Department of Agricultural Sciences, “Mediterranea” University of Reggio Calabria, Feo di Vito, 89124 Reggio Calabria, Italy; (R.V.); (M.R.A.); (C.M.M.); (V.L.A.L.); (G.S.)
| | - Agostino Sorgonà
- Department of Agricultural Sciences, “Mediterranea” University of Reggio Calabria, Feo di Vito, 89124 Reggio Calabria, Italy; (R.V.); (M.R.A.); (C.M.M.); (V.L.A.L.); (G.S.)
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Tserej O, Feeley KJ. Variation in leaf temperatures of tropical and subtropical trees are related to leaf thermoregulatory traits and not geographic distributions. Biotropica 2021. [DOI: 10.1111/btp.12919] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Olga Tserej
- Biology Department University of Miami Coral Gables FL USA
- Fairchild Tropical Botanic Garden Coral Gables FL USA
| | - Kenneth J. Feeley
- Biology Department University of Miami Coral Gables FL USA
- Fairchild Tropical Botanic Garden Coral Gables FL USA
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Fanourakis D, Aliniaeifard S, Sellin A, Giday H, Körner O, Rezaei Nejad A, Delis C, Bouranis D, Koubouris G, Kambourakis E, Nikoloudakis N, Tsaniklidis G. Stomatal behavior following mid- or long-term exposure to high relative air humidity: A review. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2020; 153:92-105. [PMID: 32485617 DOI: 10.1016/j.plaphy.2020.05.024] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Accepted: 05/21/2020] [Indexed: 05/07/2023]
Abstract
High relative air humidity (RH ≥ 85%) is frequent in controlled environments, and not uncommon in nature. In this review, we examine the high RH effects on plants with a special focus on stomatal characters. All aspects of stomatal physiology are attenuated by elevated RH during leaf expansion (long-term) in C3 species. These include impaired opening and closing response, as well as weak diel oscillations. Consequently, the high RH-grown plants are not only vulnerable to biotic and abiotic stress, but also undergo a deregulation between CO2 uptake and water loss. Stomatal behavior of a single leaf is determined by the local microclimate during expansion, and may be different than the remaining leaves of the same plant. No effect of high RH is apparent in C4 and CAM species, while the same is expected for species with hydropassive stomatal closure. Formation of bigger stomata with larger pores is a universal response to high RH during leaf expansion, whereas the effect on stomatal density appears to be species- and leaf side-specific. Compelling evidence suggests that ABA mediates the high RH-induced stomatal malfunction, as well as the stomatal size increase. Although high RH stimulates leaf ethylene evolution, it remains elusive whether or not this contributes to stomatal malfunction. Most species lose stomatal function following mid-term (4-7 d) exposure to high RH following leaf expansion. Consequently, the regulatory role of ambient humidity on stomatal functionality is not limited to the period of leaf expansion, but holds throughout the leaf life span.
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Affiliation(s)
- Dimitrios Fanourakis
- Department of Agriculture, School of Agricultural Sciences, Hellenic Mediterranean University, Estavromenos, GR-71500, Heraklion, Greece; Giannakakis SA, Export Fruits and Vegetables, Tympaki, Greece.
| | - Sasan Aliniaeifard
- Department of Horticulture, College of Aburaihan, University of Tehran, Pakdasht, Tehran, Iran
| | - Arne Sellin
- Institute of Ecology and Earth Sciences, University of Tartu, Lai 40, Tartu, 51005, Estonia
| | - Habtamu Giday
- International Center for Biosaline Agriculture, ICBA, P.O. Box 14660, Dubai, United Arab Emirates
| | - Oliver Körner
- Leibniz-Institute of Vegetable and Ornamental Crops (IGZ), Grossbeeren, Germany
| | - Abdolhossein Rezaei Nejad
- Department of Horticultural Sciences, Faculty of Agriculture, Lorestan University, P.O. Box 465, Khorramabad, Iran
| | - Costas Delis
- Department of Agriculture, University of the Peloponnese, GR-24100, Kalamata, Greece
| | - Dimitris Bouranis
- Plant Physiology and Morphology Laboratory, Crop Science Department, Agricultural University of Athens, Athens, Greece
| | - Georgios Koubouris
- Laboratory of Olive Cultivation, Institute of Olive Tree, Subtropical Crops and Viticulture, Hellenic Agricultural Organization Demeter, Crete, Greece
| | - Emmanouil Kambourakis
- Department of Agriculture, School of Agricultural Sciences, Hellenic Mediterranean University, Estavromenos, GR-71500, Heraklion, Greece
| | - Nikolaos Nikoloudakis
- Cyprus University of Technology, Department of Agricultural Sciences, Biotechnology and Food Science, Cyprus
| | - Georgios Tsaniklidis
- Institute of Olive Tree, Subtropical Plants and Viticulture, Hellenic Agricultural Organization 'Demeter' (NAGREF), P.O. Box 2228, 71003, Heraklio, Greece
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40
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Song Y, Xuan A, Bu C, Liu X, Zhang D. Identification of a transcriptional regulatory module that reduces leaf temperature in poplar under heat stress. TREE PHYSIOLOGY 2020; 40:1108-1125. [PMID: 32159812 DOI: 10.1093/treephys/tpaa025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Revised: 02/02/2020] [Accepted: 02/26/2020] [Indexed: 06/10/2023]
Abstract
A stable leaf temperature provides plants with a suitable microenvironment for photosynthesis. With global warming, extreme temperatures have become more frequent and severe; therefore, it is increasingly important to understand the fine regulation of leaf temperature under heat stress. In this study, five poplar species (Populus tomentosa, Populus simonii, Populus euphratica, Populus deltoides and Populus trichocarpa) that live in different native environments were used to analyze leaf temperature regulation. Leaf temperatures were more stable in Populus simonii and Populus euphratica (adapted to water-deficient regions) under elevated ambient temperature. Although transpiration contributes strongly to leaf cooling in poplar, the thicker epidermis and mesophyll and lower absorbance of Populus simonii and Populus euphratica leaves also help reduce leaf temperature, since their leaves absorb less radiation. Co-expression network and association analysis of a natural population of P. simonii indicated that PsiMYB60.2, PsiMYB61.2 and PsiMYB61.1 play dominant roles in coordinating leaf temperature, stomatal conductance and transpiration rate in response to heat stress. Individuals with CT-GT-GT genotypes of these three candidate genes have significantly higher water-use efficiency, and balance leaf temperature cooling with photosynthetic efficiency. Therefore, our findings have clarified the genetic basis of leaf cooling among poplar species and laid the foundation for molecular breeding of thermostable, water-conserving poplar varieties.
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Affiliation(s)
- Yuepeng Song
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, P.R. China
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, P.R. China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, P.R. China
| | - Anran Xuan
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, P.R. China
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, P.R. China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, P.R. China
| | - Chenhao Bu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, P.R. China
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, P.R. China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, P.R. China
| | - Xiaoge Liu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, P.R. China
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, P.R. China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, P.R. China
| | - Deqiang Zhang
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, P.R. China
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, P.R. China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, P.R. China
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41
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Yuan X, Laakso K, Davis CD, Guzmán Q. JA, Meng Q, Sanchez-Azofeifa A. Monitoring the Water Stress of an Indoor Living Wall System Using the "Triangle Method". SENSORS 2020; 20:s20113261. [PMID: 32521711 PMCID: PMC7308895 DOI: 10.3390/s20113261] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 06/03/2020] [Accepted: 06/04/2020] [Indexed: 11/29/2022]
Abstract
Living walls are important vertical greening systems with modular prevegetated structures. Studies have suggested that living walls have many social benefits as an ecological engineering technique with notable potential for reconciliation ecology. Despite these benefits, there are currently no mature workflows or technologies for monitoring the health status and water stress of living wall systems. To partially fill the current knowledge gap related to water stress, we acquired thermal, multispectral, and hyperspectral remote sensing data from an indoor living wall in the Cloud Forest of the Gardens by the Bay, Singapore. The surface temperature (Ts) and a normalized difference vegetation index (NDVI) were obtained from these data to construct a Ts-NDVI space for applying the “triangle method”. A simple and effective algorithm was proposed to determine the dry and wet edges, the key components of the said method. The pixels associated with the dry and wet edges were then selected and highlighted to directly display the areas under water-stress conditions. Our results suggest that the proposed algorithm can provide a reasonable overview of the water-stress information of the living wall; therefore, our method can be simple and effective to monitor the health status of a living wall. Furthermore, our work confirms that the triangle method can be transferred from the outdoors to an indoor environment.
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Affiliation(s)
- Xu Yuan
- State Key Laboratory of Subtropical Building Science, South China University of Technology, Guangzhou 510641, China; (X.Y.); (Q.M.)
- Centre for Earth Observation Sciences (CEOS), Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, AB T6G 2E3, Canada; (K.L.); (J.A.G.Q.)
| | - Kati Laakso
- Centre for Earth Observation Sciences (CEOS), Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, AB T6G 2E3, Canada; (K.L.); (J.A.G.Q.)
| | | | - J. Antonio Guzmán Q.
- Centre for Earth Observation Sciences (CEOS), Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, AB T6G 2E3, Canada; (K.L.); (J.A.G.Q.)
| | - Qinglin Meng
- State Key Laboratory of Subtropical Building Science, South China University of Technology, Guangzhou 510641, China; (X.Y.); (Q.M.)
| | - Arturo Sanchez-Azofeifa
- Centre for Earth Observation Sciences (CEOS), Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, AB T6G 2E3, Canada; (K.L.); (J.A.G.Q.)
- Correspondence:
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42
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Jagadish SVK. Heat stress during flowering in cereals - effects and adaptation strategies. THE NEW PHYTOLOGIST 2020; 226:1567-1572. [PMID: 31943230 DOI: 10.1111/nph.16429] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 12/15/2019] [Indexed: 05/11/2023]
Abstract
Heat stress during flowering has differential impact on male and female reproductive organ viability leading to yield losses in field crops. Unlike flooded rice, dryland cereals such as sorghum, pearl millet and wheat have optimised their flower opening during cooler early morning or late evening hours to lower heat stress damage during flowering. Although previous studies have concluded that pollen viability determines seed set under heat stress, recent findings have revealed pearl millet and sorghum pistils to be equally sensitive to heat stress. Integrating flower opening time during cooler hours with increased pollen and pistil viability will overcome heat stress-induced damage during flowering under current and future hotter climatic conditions.
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43
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Aparecido LMT, Woo S, Suazo C, Hultine KR, Blonder B. High water use in desert plants exposed to extreme heat. Ecol Lett 2020; 23:1189-1200. [PMID: 32436365 DOI: 10.1111/ele.13516] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 03/22/2020] [Accepted: 03/25/2020] [Indexed: 01/06/2023]
Abstract
Many plant water use models predict leaves maximize carbon assimilation while minimizing water loss via transpiration. Alternate scenarios may occur at high temperature, including heat avoidance, where leaves increase water loss to evaporatively cool regardless of carbon uptake; or heat failure, where leaves non-adaptively lose water also regardless of carbon uptake. We hypothesized that these alternative scenarios are common in species exposed to hot environments, with heat avoidance more common in species with high construction cost leaves. Diurnal measurements of leaf temperature and gas exchange for 11 Sonoran Desert species revealed that 37% of these species increased transpiration in the absence of increased carbon uptake. High leaf mass per area partially predicted this behaviour (r2 = 0.39). These data are consistent with heat avoidance and heat failure, but failure is less likely given the ecological dominance of the focal species. These behaviours are not yet captured in any extant plant water use model.
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Affiliation(s)
- Luiza M T Aparecido
- School of Life Sciences, Arizona State University, 427 E Tyler Mall, Tempe, AZ, 85821, USA
| | - Sabrina Woo
- School of Life Sciences, Arizona State University, 427 E Tyler Mall, Tempe, AZ, 85821, USA
| | - Crystal Suazo
- School of Life Sciences, Arizona State University, 427 E Tyler Mall, Tempe, AZ, 85821, USA
| | - Kevin R Hultine
- Department of Research, Conservation and Collections, Desert Botanical Garden, 1201 N. Galvin Parkway, Phoenix, AZ, 85008, USA
| | - Benjamin Blonder
- School of Life Sciences, Arizona State University, 427 E Tyler Mall, Tempe, AZ, 85821, USA.,Environmental Change Institute, School of Geography and the Environment, University of Oxford, South Parks Road, Oxford, OX1 3QY, UK.,Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA, 94720, USA
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44
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Marchin RM, Ossola A, Leishman MR, Ellsworth DS. A Simple Method for Simulating Drought Effects on Plants. FRONTIERS IN PLANT SCIENCE 2020; 10:1715. [PMID: 32038685 PMCID: PMC6985571 DOI: 10.3389/fpls.2019.01715] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 12/05/2019] [Indexed: 05/05/2023]
Abstract
Drought is expected to increase in frequency and severity in many regions in the future, so it is important to improve our understanding of how drought affects plant functional traits and ecological interactions. Imposing experimental water deficits is key to gaining this understanding, but has been hindered by logistic difficulties in maintaining consistently low water availability for plants. Here, we describe a simple method for applying soil water deficits to potted plants in glasshouse experiments. We modified an existing method (the "Snow and Tingey system") in order to apply a gradual, moderate water deficit to 50 plant species of different life forms (grasses, vines, shrubs, trees). The method requires less maintenance and manual handling compared to other water deficit methods, so it can be used for extended periods of time and is relatively inexpensive to implement. With only a few modifications, it is possible to easily establish and maintain soil water deficits of differing intensity and duration, as well as to incorporate interacting stress factors. We tested this method by measuring physiological responses to an applied water deficit in a subset of 11 tree/shrub species with a wide range of drought tolerances and water-use strategies. For this subgroup of species, stomatal conductance was 2-17 times lower in droughted plants than controls, although only half of the species (5 out of 11) experienced midday leaf water potentials that exceeded their turgor loss (i.e., wilting) point. Leaf temperatures were up to 8°C higher in droughted plants than controls, indicating that droughted plants are at greater risk of thermal damage, relative to unstressed plants. The largest leaf temperature differences (between droughted and well-watered plants) were in species with high rates of water loss. Rapid osmotic adjustment was observed in leaves of five species when drought stress was combined with an experimental heatwave. These results highlight the potential value of further ecological and physiological experiments utilizing this simple water deficit method to study plant responses to drought stress.
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Affiliation(s)
- Renée M. Marchin
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Alessandro Ossola
- Department of Biological Sciences, Macquarie University, North Ryde, NSW, Australia
| | - Michelle R. Leishman
- Department of Biological Sciences, Macquarie University, North Ryde, NSW, Australia
| | - David S. Ellsworth
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
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Mediavilla S, Martín I, Babiano J, Escudero A. Foliar plasticity related to gradients of heat and drought stress across crown orientations in three Mediterranean Quercus species. PLoS One 2019; 14:e0224462. [PMID: 31658291 PMCID: PMC6816560 DOI: 10.1371/journal.pone.0224462] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 10/14/2019] [Indexed: 01/20/2023] Open
Abstract
Studies on plasticity at the level of a single individual plant provide indispensable information to predict leaf responses to climate change, because they allow better identification of the environmental factors that determine differences in leaf traits in the absence of genetic differences. Most of these studies have focused on the responses of leaf traits to variations in the light environment along vertical gradients, thus paying less attention to possible differences in the intensity of water stress among canopy orientations. In this paper, we analyzed the differences in leaf traits traditionally associated with changes in the intensity of water stress between east and west crown orientations in three Quercus species. The leaves facing west experienced similar solar radiation levels but higher maximum temperatures and lower daily minimum water potentials than those of the east orientation. In response to these differences, the leaves of the west orientation showed smaller size and less chlorophyll concentration, higher percentage of palisade tissue and higher density of stomata and trichomes. These responses would confirm the role of such traits in the tolerance to water stress and control of water losses by transpiration. For all traits, the species with the longest leaf life span exhibited the greatest plasticity between orientations. By contrast, no differences between canopy positions were observed for leaf thickness, leaf mass per unit area and venation patterns.
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Affiliation(s)
- Sonia Mediavilla
- Área de Ecología, Facultad de Biología, Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain
| | - Ignacio Martín
- Dpto. de Botánica y Fisiología Vegetal, Facultad de Biología, Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain
| | - Josefa Babiano
- Dpto. de Botánica y Fisiología Vegetal, Facultad de Biología, Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain
| | - Alfonso Escudero
- Área de Ecología, Facultad de Biología, Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain
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46
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Canopy Temperature Differences between Liana-Infested and Non-Liana Infested Areas in a Neotropical Dry Forest. FORESTS 2019. [DOI: 10.3390/f10100890] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Lianas (woody vines) are important non-structural elements of all tropical forests. Current field observations across the Neotropics suggest that liana abundance is rising as a result of forest disturbance, increasing atmospheric CO2, and more frequent extreme climate events. Lianas can cause mechanical stress on their host trees, thus increasing mortality, in addition to potentially reducing carbon storage capacity. Furthermore, previous studies have suggested that liana leaves have an overall higher temperature than tree leaves, which presents the question of whether these differences can be extended from the leaf to the canopy. In this context, the ability to detect these temperature differences from a remote sensing platform has so far not been put into test, despite the importance such knowledge can have in large-scale land surface modeling studies and liana extent monitoring. To partially fill this knowledge gap, we acquired thermal infrared data using an unmanned aerial vehicle (UAV) system over an intermediate tropical dry forest in Costa Rica, Central America. Classification results from a previous study in the same area were used to subset the thermal infrared images into liana-infested areas, non-liana infested areas, and forest gaps. The temperature differences between these three image components were then investigated using the Welch and Games–Howell post-hoc statistical tests. Our results suggest that liana-infested areas have, on average, a statistically significant higher temperature than non-liana infested areas. Shadowed forest gaps, used as reference, have a cooler temperature than forest canopies. Our findings on the temperature differences between liana-infested and non-liana infested areas support previous leaf-level observations and open the door to the use of new approaches for the classification and modeling of liana infestation in tropical ecosystems.
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47
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Massmann A, Gentine P, Lin C. When Does Vapor Pressure Deficit Drive or Reduce Evapotranspiration? JOURNAL OF ADVANCES IN MODELING EARTH SYSTEMS 2019; 11:3305-3320. [PMID: 31894191 PMCID: PMC6919419 DOI: 10.1029/2019ms001790] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 09/06/2019] [Accepted: 09/12/2019] [Indexed: 05/30/2023]
Abstract
Increasing vapor pressure deficit (VPD) increases atmospheric demand for water. While increased evapotranspiration (ET) in response to increased atmospheric demand seems intuitive, plants are capable of reducing ET in response to increased VPD by closing their stomata. We examine which effect dominates the response to increasing VPD: atmospheric demand and increases in ET or plant response (stomata closure) and decreases in ET. We use Penman-Monteith, combined with semiempirical optimal stomatal regulation theory and underlying water use efficiency, to develop a theoretical framework for assessing ET response to VPD. The theory suggests that depending on the environment and plant characteristics, ET response to increasing VPD can vary from strongly decreasing to increasing, highlighting the diversity of plant water regulation strategies. The ET response varies due to (1) climate, with tropical and temperate climates more likely to exhibit a positive ET response to increasing VPD than boreal and arctic climates; (2) photosynthesis strategy, with C3 plants more likely to exhibit a positive ET response than C4 plants; and (3) plant type, with crops more likely to exhibit a positive ET response, and shrubs and gymniosperm trees more likely to exhibit a negative ET response. These results, derived from previous literature connecting plant parameters to plant and climate characteristics, highlight the utility of our simplified framework for understanding complex land-atmosphere systems in terms of idealized scenarios in which ET responds to VPD only. This response is otherwise challenging to assess in an environment where many processes coevolve together.
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Affiliation(s)
- Adam Massmann
- Department of Earth and Environmental EngineeringColumbia UniversityNew YorkNYUSA
| | - Pierre Gentine
- Department of Earth and Environmental EngineeringColumbia UniversityNew YorkNYUSA
| | - Changjie Lin
- Department of Earth and Environmental EngineeringColumbia UniversityNew YorkNYUSA
- State Key Laboratory of Hydroscience and Engineering, Department of Hydraulic EngineeringTsinghua UniversityBeijingChina
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48
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Massmann A, Gentine P, Lin C. When Does Vapor Pressure Deficit Drive or Reduce Evapotranspiration? JOURNAL OF ADVANCES IN MODELING EARTH SYSTEMS 2019; 11:3305-3320. [PMID: 31894191 DOI: 10.5194/hess-2018-553] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 09/06/2019] [Accepted: 09/12/2019] [Indexed: 05/24/2023]
Abstract
Increasing vapor pressure deficit (VPD) increases atmospheric demand for water. While increased evapotranspiration (ET) in response to increased atmospheric demand seems intuitive, plants are capable of reducing ET in response to increased VPD by closing their stomata. We examine which effect dominates the response to increasing VPD: atmospheric demand and increases in ET or plant response (stomata closure) and decreases in ET. We use Penman-Monteith, combined with semiempirical optimal stomatal regulation theory and underlying water use efficiency, to develop a theoretical framework for assessing ET response to VPD. The theory suggests that depending on the environment and plant characteristics, ET response to increasing VPD can vary from strongly decreasing to increasing, highlighting the diversity of plant water regulation strategies. The ET response varies due to (1) climate, with tropical and temperate climates more likely to exhibit a positive ET response to increasing VPD than boreal and arctic climates; (2) photosynthesis strategy, with C3 plants more likely to exhibit a positive ET response than C4 plants; and (3) plant type, with crops more likely to exhibit a positive ET response, and shrubs and gymniosperm trees more likely to exhibit a negative ET response. These results, derived from previous literature connecting plant parameters to plant and climate characteristics, highlight the utility of our simplified framework for understanding complex land-atmosphere systems in terms of idealized scenarios in which ET responds to VPD only. This response is otherwise challenging to assess in an environment where many processes coevolve together.
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Affiliation(s)
- Adam Massmann
- Department of Earth and Environmental Engineering Columbia University New York NY USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering Columbia University New York NY USA
| | - Changjie Lin
- Department of Earth and Environmental Engineering Columbia University New York NY USA
- State Key Laboratory of Hydroscience and Engineering, Department of Hydraulic Engineering Tsinghua University Beijing China
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49
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Leaf Temperature and Vapour Pressure Deficit (VPD) Driving Stomatal Conductance and Biochemical Processes of Leaf Photosynthetic Rate in a Subtropical Evergreen Coniferous Plantation. SUSTAINABILITY 2018. [DOI: 10.3390/su10114063] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Photosynthesis is arguably the most important biochemical process on Earth, which is dramatically influenced by environmental conditions. How environmental factors drive stomatal conductance and biochemical processes of leaf photosynthetic rate has not been sufficiently investigated in subtropical China. In this study, we analysed the effects of stomatal and biochemical parameters on the photosynthetic rate of native Masson’s pine (Pinus massoniana Lamb.) and exotic slash pine (Pinus elliottii Engelm.) in response to leaf temperature and vapour pressure deficit (VPD) in subtropical China, based on leaf gas exchange measurements in 2016. Our results showed that there was no significant difference in the light-saturated photosynthetic rate (Asat) between native Masson’s pine and exotic slash pine. The seasonal patterns of maximum rate of the carboxylation (Vcmax25) were basically consistent with seasonal patterns of Asat for both species. The positive effect of leaf temperature on Asat was mainly produced through its positive effect on Vcmax25. Leaf temperature had no significant effect on stomatal conductance. Vcmax25 and gs simultaneously affected Asat in response to VPD. Our results highlighted the importance of biochemical processes in limiting leaf photosynthetic rate in response to environmental conditions in subtropical evergreen coniferous plantations.
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50
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Fontes CG, Dawson TE, Jardine K, McDowell N, Gimenez BO, Anderegg L, Negrón-Juárez R, Higuchi N, Fine PVA, Araújo AC, Chambers JQ. Dry and hot: the hydraulic consequences of a climate change-type drought for Amazonian trees. Philos Trans R Soc Lond B Biol Sci 2018; 373:20180209. [PMID: 30297481 PMCID: PMC6178441 DOI: 10.1098/rstb.2018.0209] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/17/2018] [Indexed: 11/12/2022] Open
Abstract
How plants respond physiologically to leaf warming and low water availability may determine how they will perform under future climate change. In 2015-2016, an unprecedented drought occurred across Amazonia with record-breaking high temperatures and low soil moisture, offering a unique opportunity to evaluate the performances of Amazonian trees to a severe climatic event. We quantified the responses of leaf water potential, sap velocity, whole-tree hydraulic conductance (Kwt), turgor loss and xylem embolism, during and after the 2015-2016 El Niño for five canopy-tree species. Leaf/xylem safety margins (SMs), sap velocity and Kwt showed a sharp drop during warm periods. SMs were negatively correlated with vapour pressure deficit, but had no significant relationship with soil water storage. Based on our calculations of canopy stomatal and xylem resistances, the decrease in sap velocity and Kwt was due to a combination of xylem cavitation and stomatal closure. Our results suggest that warm droughts greatly amplify the degree of trees' physiological stress and can lead to mortality. Given the extreme nature of the 2015-2016 El Niño and that temperatures are predicted to increase, this work can serve as a case study of the possible impact climate warming can have on tropical trees.This article is part of a discussion meeting issue 'The impact of the 2015/2016 El Niño on the terrestrial tropical carbon cycle: patterns, mechanisms and implications'.
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Affiliation(s)
- Clarissa G Fontes
- Department of Integrative Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Todd E Dawson
- Department of Integrative Biology, University of California at Berkeley, Berkeley, CA 94720, USA
- Ecosystem Science Division, Department of Science, Policy and Management, Environmental University of California Berkeley, Berkeley, CA, USA
| | - Kolby Jardine
- Climate Science Department, Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 74, Berkeley, CA 94720, USA
- Ciências de Florestas Tropicais, Instituto Nacional de Pesquisas da Amazônia (INPA), Manaus-AM 69067-375, Brazil
| | - Nate McDowell
- Pacific Northwest National Laboratory, Richland, WA, USA
| | - Bruno O Gimenez
- Ciências de Florestas Tropicais, Instituto Nacional de Pesquisas da Amazônia (INPA), Manaus-AM 69067-375, Brazil
| | - Leander Anderegg
- Department of Integrative Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Robinson Negrón-Juárez
- Climate Science Department, Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 74, Berkeley, CA 94720, USA
| | - Niro Higuchi
- Ciências de Florestas Tropicais, Instituto Nacional de Pesquisas da Amazônia (INPA), Manaus-AM 69067-375, Brazil
| | - Paul V A Fine
- Department of Integrative Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Alessandro C Araújo
- Department of Global Ecology, Carnegie Institution for Science, 260 Panama St., Stanford, CA 94305, USA
- Embrapa Amazônia Oriental, Trav. Dr. Enéas Pinheiro, Belém, Pará 66095-100, Brazil
| | - Jeffrey Q Chambers
- Climate Science Department, Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 74, Berkeley, CA 94720, USA
- Department of Geography, University of California Berkeley, 507 McCone Hall #4740, Berkeley, CA 94720, USA
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