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Zhu LW, Li YQ, Lu LW, Wang JY, Du J, Zhao P. Temporal dynamics of stomatal regulation and carbon- and water-related traits for a native tree species in low subtropical China. Tree Physiol 2024:tpae016. [PMID: 38281184 DOI: 10.1093/treephys/tpae016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2024]
Abstract
Stomata are pivotal in modulating water and carbon processes within plants. However, our understanding of the temporal dynamics of water- and carbon-related traits, as influenced by stomatal behavior, remains limited. Here, we explore how stomatal regulation behavior and water- and carbon-related traits vary with changing environments by examining the seasonal variations in these traits of the native tree species Schima superba in low subtropical China. In February, April, and July of 2022, a series of water- and carbon-related traits were measured in the leaves and stems. The results showed that S. superba exhibited isohydric behavior in February when the soil dried out and vapor pressure deficit (VPD) was lower but anisohydric behavior in April and July when the soil was wetter and VPD was higher. In February, NSC and their components increased, and a relatively large contribution of soluble sugars to the change in NSC was observed. In the branches and phloem, NSC and their components displayed a relatively high monthly variability, suggesting their role in maintaining carbon balance within the trees. Conversely, the NSC in the leaves demonstrated minimal monthly variability. The specific leaf area, as well as the concentration of nitrogen (N) and phosphorus (P) per unit mass in leaves and the cumulative stem water release, exhibited a decrease with a reduction in soil water potential. Interestingly, the hydraulic conductivity remained consistent throughout this process. Furthermore, the relatively low monthly growth rate observed in February could suggest a carbon sink limitation. In conclusion, the increased NSC and decreased water status of S. superba under relatively stressed soil conditions indicated a trade-off between water and carbon storage. Our findings enhance our comprehension of the dynamics and regulation of water and carbon status in forests, thereby advancing the development of plant carbon and water process models under climate change scenarios.
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Affiliation(s)
- Li-Wei Zhu
- South China Botanical Garden, Chinese Academy of Sciences
- South China National Botanical Garden, Guangzhou, Guangdong, China
| | - Yan-Qiong Li
- South China Botanical Garden, Chinese Academy of Sciences
- South China National Botanical Garden, Guangzhou, Guangdong, China
| | - Long-Wei Lu
- South China Botanical Garden, Chinese Academy of Sciences
- South China National Botanical Garden, Guangzhou, Guangdong, China
| | - Jing-Yi Wang
- South China Botanical Garden, Chinese Academy of Sciences
- South China National Botanical Garden, Guangzhou, Guangdong, China
| | - Jie Du
- South China Botanical Garden, Chinese Academy of Sciences
- South China National Botanical Garden, Guangzhou, Guangdong, China
| | - Ping Zhao
- South China Botanical Garden, Chinese Academy of Sciences
- South China National Botanical Garden, Guangzhou, Guangdong, China
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2
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Horvat B, Shikakura Y, Ohtani M, Demura T, Kikuchi A, Watanabe KN, Oguchi T. Heterogeneous Expression of Arabidopsis Subclass II of SNF1-Related Kinase 2 Improves Drought Tolerance via Stomatal Regulation in Poplar. Life (Basel) 2024; 14:161. [PMID: 38276290 PMCID: PMC10817443 DOI: 10.3390/life14010161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 12/28/2023] [Accepted: 01/20/2024] [Indexed: 01/27/2024] Open
Abstract
Abscisic acid (ABA) is the most important phytohormone involved in the response to drought stress. Subclass II of SNF1-related kinase 2 (SnRK2) is an important signaling kinase related to ABA signal transduction. It regulates the phosphorylation of the target transcription factors controlling the transcription of a wide range of ABA-responsive genes in Arabidopsis thaliana. The transgenic poplars (Populus tremula × P. tremuloides, clone T89) ectopically overexpressing AtSnRK2.8, encoding a subclass II SnRK2 kinase of A. thaliana, have been engineered but almost no change in its transcriptome was observed. In this study, we evaluated osmotic stress tolerance and stomatal behavior of the transgenic poplars maintained in the netted greenhouse. The transgenic poplars, line S22, showed a significantly higher tolerance to 20% PEG treatment than non-transgenic controls. The stomatal conductance of the transgenic poplars tended to be lower than the non-transgenic control. Microscopic observations of leaf imprints revealed that the transgenic poplars had significantly higher stomatal closures under the stress treatment than the non-transgenic control. In addition, the stomatal index was lower in the transgenic poplars than in the non-transgenic controls regardless of the stress treatment. These results suggested that AtSnRK2.8 is involved in the regulation of stomatal behavior. Furthermore, the transgenic poplars overexpressing AtSnRK2.8 might have improved abiotic stress tolerance through this stomatal regulation.
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Affiliation(s)
- Borislav Horvat
- Degree Program in Life and Earth Science, Graduate School of Science and Technology, University of Tsukuba, Tsukuba 305-8572, Ibaraki, Japan
| | - Yuhei Shikakura
- Degree Program in Life and Earth Science, Graduate School of Science and Technology, University of Tsukuba, Tsukuba 305-8572, Ibaraki, Japan
| | - Misato Ohtani
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8562, Chiba, Japan
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Kanagawa, Japan
| | - Taku Demura
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Kanagawa, Japan
- Center for Digital Green-Innovation, Nara Institute of Science and Technology, Ikoma 630-0192, Nara, Japan
| | - Akira Kikuchi
- Institute of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-8572, Ibaraki, Japan
- Tsukuba Plant Innovation Research Center, University of Tsukuba, Tsukuba 305-8572, Ibaraki, Japan
| | - Kazuo N. Watanabe
- Institute of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-8572, Ibaraki, Japan
- Tsukuba Plant Innovation Research Center, University of Tsukuba, Tsukuba 305-8572, Ibaraki, Japan
| | - Taichi Oguchi
- Institute of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-8572, Ibaraki, Japan
- Tsukuba Plant Innovation Research Center, University of Tsukuba, Tsukuba 305-8572, Ibaraki, Japan
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Maleki FA, Seidl-Adams I, Fahimi A, Peiffer ML, Kersch-Becker MF, Felton GW, Tumlinson JH. Stomatal closure prevents xylem transport of green leaf volatiles and impairs their systemic function in plants. Plant Cell Environ 2024; 47:122-139. [PMID: 37828776 DOI: 10.1111/pce.14735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 09/29/2023] [Accepted: 10/02/2023] [Indexed: 10/14/2023]
Abstract
Plants perceive environmental stresses as whole organisms via distant signals conveying danger messages through their vasculature. In parallel to vascular transport, airborne plant volatile compounds, including green leaf volatiles (GLVs), can bypass the lack of vascular connection. However, some small volatile compounds move through the vasculature; such vascular transport is little known about GLVs. Here we illustrate GLV alcohols as solutes move within xylem vessels in Zea mays. We describe GLV alcohols, including Z-3-hexen-ol and its isomer E-3-hexen-ol, which is not synthesized in maize, moving through the transpiration stream via xylem vessels. Since transpiration is mediated by the stomatal aperture, closing stomata by two independent methods diminishes the transport of GLV alcohol and its isomer. In addition, the lower transport of GLV alcohols impairs their function in inducing terpenoid biosynthesis, suggesting that xylem transport of GLV alcohols plays a significant role in their systemic function. Our study suggests that GLV alcohols, in addition to airborne signals, are transported through xylem vessels. Our findings can be critical in future studies about the perception and function of these compounds in plants.
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Affiliation(s)
- Feizollah A Maleki
- Center of Chemical Ecology, Entomology Department, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Irmgard Seidl-Adams
- Center of Chemical Ecology, Entomology Department, The Pennsylvania State University, University Park, Pennsylvania, USA
| | | | - Michelle L Peiffer
- Center of Chemical Ecology, Entomology Department, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Monica F Kersch-Becker
- Center of Chemical Ecology, Entomology Department, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Gary W Felton
- Center of Chemical Ecology, Entomology Department, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - James H Tumlinson
- Center of Chemical Ecology, Entomology Department, The Pennsylvania State University, University Park, Pennsylvania, USA
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Sorek Y, Netzer Y, Cohen S, Hochberg U. Rapid leaf xylem acclimation diminishes the chances of embolism in grapevines. J Exp Bot 2023; 74:6836-6846. [PMID: 37659088 DOI: 10.1093/jxb/erad351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Accepted: 09/01/2023] [Indexed: 09/04/2023]
Abstract
Under most conditions tight stomatal regulation in grapevines (Vitis vinifera) avoids xylem embolism. The current study evaluated grapevine responses to challenging scenarios that might lead to leaf embolism and consequential leaf damage. We hypothesized that embolism would occur if the vines experienced low xylem water potential (Ψx) shortly after bud break or later in the season under a combination of extreme drought and heat. We subjected vines to two potentially dangerous environments: (i) withholding irrigation from a vineyard grown in a heatwave-prone environment, and (ii) subjecting potted vines to terminal drought 1 month after bud break. In the field experiment, a heatwave at the beginning of August resulted in leaf temperatures over 45 °C. However, effective stomatal response maintained the xylem water potential (Ψx) well above the embolism threshold, and no leaf desiccation was observed. In the pot experiment, leaves of well-watered vines in May were relatively vulnerable to embolism with 50% embolism (P50) at -1.8 MPa. However, when exposed to drought, these leaves acclimated their leaf P50 by 0.65 MPa in less than a week and before reaching embolism values. When dried to embolizing Ψx, the leaf damage proportion matched (percentage-wise) the leaf embolism level. Our findings indicate that embolism and leaf damage are usually avoided by the grapevines' efficient stomatal regulation and rapid acclimation of their xylem vulnerability.
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Affiliation(s)
- Yonatan Sorek
- Institute of Soil, Water and Environmental Sciences, Volcani Center, Agricultural Research Organization, Rishon LeZion, Israel
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Yishai Netzer
- Department of Chemical Engineering, Ariel University, Ariel 40700, Israel
- Eastern R and D Center, Ariel 40700, Israel
| | - Shabtai Cohen
- Institute of Soil, Water and Environmental Sciences, Volcani Center, Agricultural Research Organization, Rishon LeZion, Israel
| | - Uri Hochberg
- Institute of Soil, Water and Environmental Sciences, Volcani Center, Agricultural Research Organization, Rishon LeZion, Israel
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Hu XC, Gao WT, Sun SJ, Zhang JS, Meng P, Cai JF. [Responses of tree growth and intrinsic water-use efficiency of Robinia pseudoacacia to climate factors]. Ying Yong Sheng Tai Xue Bao 2023; 34:2610-2618. [PMID: 37897267 DOI: 10.13287/j.1001-9332.202310.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 10/30/2023]
Abstract
We investigated tree growth in Robinia pseudoacacia plantations at Ansai in Shaanxi Province and at Ji-xian in Shanxi Province by comparing the tree-ring width, basal area increase (BAI), δ13C value, intrinsic water-use efficiency (iWUE), and stomatal regulation. We quantified the responses of tree growth and iWUE to climatic factors at each site. The tree-ring width at Ansai and Jixian decreased with stand age, whereas the BAI at Ansai increased, and that at Jixian decreased after the BAI peaked. The δ13C value and iWUE of trees at Jixian were higher than those at Ansai. The iWUE of trees at both sites was similar to the constant intercellular CO2 concentration/atmospheric CO2 concentration (Ci/Ca) scenario, indicating that the Ci of trees was elevated with increasing Ca, while the stomata remained open. The BAI at Ansai was significantly positively correlated with highest temperature in May, relative humidity in June, precipitation in August, relative humidity in September, and standardized precipitation evapotranspiration index (SPEI) in September and October of current year, but negatively correlated with temperature in June. The BAI at Jixian was significantly positively correlated with SPEI in June and July, and lowest temperature in October of current year. The iWUE of trees at Ansai was significantly positively correlated with relative humidity and precipitation in June of the current year, but negatively correlated with minimum temperature in May, relative humidity in June, and temperature and maximum temperature in July of current year. A significant positive correlation between iWUE of trees at Jixian and lowest temperature in June of current year was detected. At the annual scale, the BAI of trees at Ansai was positively correlated with precipitation and SPEI, but no significant relationship was observed for trees at Jixian. However, the iWUE of trees at both sites was significantly affected by precipitation. Path analysis showed that SPEI and minimum temperature had a direct effect on BAI and iWUE of trees at Ansai, whereas precipitation and average temperature indirectly affected BAI and iWUE through SPEI. The highest temperature had a direct effect on tree growth at Jixian, whereas precipitation, minimum temperature, and average temperature had direct effects on iWUE. These results suggested that SPEI was the main climatic factor that affected the growth of R. pseudoacacia, while Ci was an important physiological factor. Our results could provide reference for the protection and management of R. pseudoacacia plantations under climate change.
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Affiliation(s)
- Xiao-Chuang Hu
- Key Laboratory of Tree Breeding and Cultivation of the State Forestry and Grassland Administration/Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
- Collaborative Innovation Center of Sustainable Forestry in Southern China, Nanjing Forest University, Nanjing 210037, China
- Henan Xiaolangdi Earth Critical Zone National Research Station on the Middle Yellow River, Jiyuan 454650, Henan, China
| | - Wan-Ting Gao
- Key Laboratory of Tree Breeding and Cultivation of the State Forestry and Grassland Administration/Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
- Collaborative Innovation Center of Sustainable Forestry in Southern China, Nanjing Forest University, Nanjing 210037, China
- Henan Xiaolangdi Earth Critical Zone National Research Station on the Middle Yellow River, Jiyuan 454650, Henan, China
| | - Shou-Jia Sun
- Key Laboratory of Tree Breeding and Cultivation of the State Forestry and Grassland Administration/Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
- Collaborative Innovation Center of Sustainable Forestry in Southern China, Nanjing Forest University, Nanjing 210037, China
- Henan Xiaolangdi Earth Critical Zone National Research Station on the Middle Yellow River, Jiyuan 454650, Henan, China
| | - Jin-Song Zhang
- Key Laboratory of Tree Breeding and Cultivation of the State Forestry and Grassland Administration/Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
- Collaborative Innovation Center of Sustainable Forestry in Southern China, Nanjing Forest University, Nanjing 210037, China
- Henan Xiaolangdi Earth Critical Zone National Research Station on the Middle Yellow River, Jiyuan 454650, Henan, China
| | - Ping Meng
- Key Laboratory of Tree Breeding and Cultivation of the State Forestry and Grassland Administration/Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
- Collaborative Innovation Center of Sustainable Forestry in Southern China, Nanjing Forest University, Nanjing 210037, China
- Henan Xiaolangdi Earth Critical Zone National Research Station on the Middle Yellow River, Jiyuan 454650, Henan, China
| | - Jin-Feng Cai
- Collaborative Innovation Center of Sustainable Forestry in Southern China, Nanjing Forest University, Nanjing 210037, China
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Cai G, Carminati A, Gleason SM, Javaux M, Ahmed MA. Soil-plant hydraulics explain stomatal efficiency-safety tradeoff. Plant Cell Environ 2023; 46:3120-3127. [PMID: 36609853 DOI: 10.1111/pce.14536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 12/10/2022] [Accepted: 01/06/2023] [Indexed: 06/17/2023]
Abstract
The efficiency-safety tradeoff has been thoroughly investigated in plants, especially concerning their capacity to transport water and avoid embolism. Stomatal regulation is a vital plant behaviour to respond to soil and atmospheric water limitation. Recently, a stomatal efficiency-safety tradeoff was reported where plants with higher maximum stomatal conductance (gmax ) exhibited greater sensitivity to stomatal closure during soil drying, that is, less negative leaf water potential at 50% gmax (ψgs50 ). However, the underlying mechanism of this gmax -ψgs50 tradeoff remains unknown. Here, we utilized a soil-plant hydraulic model, in which stomatal closure is triggered by nonlinearity in soil-plant hydraulics, to investigate such tradeoff. Our simulations show that increasing gmax is aligned with less negative ψgs50 . Plants with higher gmax (also higher transpiration) require larger quantities of water to be moved across the rhizosphere, which results in a precipitous decrease in water potential at the soil-root interface, and therefore in the leaves. We demonstrated that the gmax -ψgs50 tradeoff can be predicted based on soil-plant hydraulics, and is impacted by plant hydraulic properties, such as plant hydraulic conductance, active root length and embolism resistance. We conclude that plants may therefore adjust their growth and/or their hydraulic properties to adapt to contrasting habitats and climate conditions.
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Affiliation(s)
- Gaochao Cai
- School of Agriculture, Shenzhen Campus of Sun Yat-sen University, Shenzhen, China
| | - Andrea Carminati
- Physics of Soils and Terrestrial Ecosystems, Institute of Terrestrial Ecosystems, Department of Environmental Systems Science, ETH Zürich, Zurich, Switzerland
| | - Sean M Gleason
- United States Department of Agriculture, Water Management and Systems Research Unit, Agricultural Research Service, Fort Collins, Colorado, USA
| | - Mathieu Javaux
- Earth and Life Institute-Environmental Science, Universite catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Mutez Ali Ahmed
- Chair of Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
- Department of Land, Air and Water Resources, College of Agricultural and Environmental Sciences, University of California Davis, Davis, California, USA
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Guizani A, Askri H, Amenta ML, Defez R, Babay E, Bianco C, Rapaná N, Finetti-Sialer M, Gharbi F. Drought responsiveness in six wheat genotypes: identification of stress resistance indicators. Front Plant Sci 2023; 14:1232583. [PMID: 37780517 PMCID: PMC10534941 DOI: 10.3389/fpls.2023.1232583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 08/28/2023] [Indexed: 10/03/2023]
Abstract
Introduction Wheat (Triticum aestivum L.) is among the world's most important staple food crops. In the current climate change scenario, a better understanding of wheat response mechanisms to water stress could help to enhance its productivity in arid ecosystems. Methods In this study, water relations, gas exchange, membrane integrity, agronomic traits and molecular analysis were evaluated in six wheat genotypes (D117, Syndiouk, Tunisian durum7 (Td7), Utique, Mahmoudi AG3 and BT) subjected to drought-stress. Results and discussion For all the studied genotypes, drought stress altered leaf area, chlorophyll content, stomatal density, photosynthetic rate and water-use efficiency, while the relative water content at turgor loss point (RWC0) remained stable. Changes in osmotic potential at turgor loss point (Ψπ0), bulk modulus of elasticity (Ɛmax) and stomatal regulation, differed greatly among the studied genotypes. For the drought-sensitive genotypes AG3 and BT, no significant changes were observed in Ψπ0, whereas the stomatal conductance (gs) and transpiration rate (E) decreased under stress conditions. These two varieties avoided turgor loss during drought treatment through an accurate stomatal control, resulting in a significant reduction in yield components. On the contrary, for Syndiouk, D117, Td7 and Utique genotypes, a solute accumulation and an increase in cell wall rigidity were the main mechanisms developed during drought stress. These mechanisms were efficient in enhancing soil water uptake, limiting leaf water loss and protecting cells membranes against leakage induced by oxidative damages. Furthermore, leaf soluble sugars accumulation was the major component of osmotic adjustment in drought-stressed wheat plants. The transcriptional analysis of genes involved in the final step of the ABA biosynthesis (AAO) and in the synthesis of an aquaporin (PIP2:1) revealed distinct responses to drought stress among the selected genotypes. In the resistant genotypes, PIP2:1 was significantly upregulated whereas in the sensitive ones, its expression showed only a slight induction. Conversely, the sensitive genotypes exhibited higher levels of AAO gene expression compared to the resistant genotypes. Our results suggest that drought tolerance in wheat is regulated by the interaction between the dynamics of leaf water status and stomatal behavior. Based on our findings, Syndiouk, D117, Utique and Td7, could be used in breeding programs for developing high-yielding and drought-tolerant wheat varieties.
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Affiliation(s)
- Asma Guizani
- Laboratory of Mycology, Pathologies and Biomarkers LR16ES05, Faculty of Sciences of Tunis, University of Tunis El Manar, Tunis, Tunisia
| | - Hend Askri
- Laboratory of Valorization of Non-Conventional Water (LR16INRGREF02), National Institute of Rural Engineering, Water and Forestry, Carthage University, Tunis, Tunisia
| | - Maria Laura Amenta
- Institute of Biosciences and BioResources, National Research Council, Naples, Italy
| | - Roberto Defez
- Institute of Biosciences and BioResources, National Research Council, Naples, Italy
| | - Elyes Babay
- Laboratory of Cereals and Food Legumes, National Gene Bank of Tunisia (BNG), Tunis, Tunisia
- Agricultural Applied Biotechnology Laboratory (LR16INRAT06), Institut National de la Recherche Agronomique de Tunisie (INRAT), University of Carthage, Tunis, Tunisia
| | - Carmen Bianco
- Institute of Biosciences and BioResources, National Research Council, Naples, Italy
| | - Nicoletta Rapaná
- Institute of Biosciences and BioResources, National Research Council, Bari, Italy
| | | | - Fatma Gharbi
- Laboratory of Mycology, Pathologies and Biomarkers LR16ES05, Faculty of Sciences of Tunis, University of Tunis El Manar, Tunis, Tunisia
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Koehler T, Wankmüller FJP, Sadok W, Carminati A. Transpiration response to soil drying versus increasing vapor pressure deficit in crops: physical and physiological mechanisms and key plant traits. J Exp Bot 2023; 74:4789-4807. [PMID: 37354081 PMCID: PMC10474596 DOI: 10.1093/jxb/erad221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 06/07/2023] [Indexed: 06/26/2023]
Abstract
The water deficit experienced by crops is a function of atmospheric water demand (vapor pressure deficit) and soil water supply over the whole crop cycle. We summarize typical transpiration response patterns to soil and atmospheric drying and the sensitivity to plant hydraulic traits. We explain the transpiration response patterns using a soil-plant hydraulic framework. In both cases of drying, stomatal closure is triggered by limitations in soil-plant hydraulic conductance. However, traits impacting the transpiration response differ between the two drying processes and act at different time scales. A low plant hydraulic conductance triggers an earlier restriction in transpiration during increasing vapor pressure deficit. During soil drying, the impact of the plant hydraulic conductance is less obvious. It is rather a decrease in the belowground hydraulic conductance (related to soil hydraulic properties and root length density) that is involved in transpiration down-regulation. The transpiration response to increasing vapor pressure deficit has a daily time scale. In the case of soil drying, it acts on a seasonal scale. Varieties that are conservative in water use on a daily scale may not be conservative over longer time scales (e.g. during soil drying). This potential independence of strategies needs to be considered in environment-specific breeding for yield-based drought tolerance.
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Affiliation(s)
- Tina Koehler
- Physics of Soils and Terrestrial Ecosystems, Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland
- Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
| | - Fabian J P Wankmüller
- Physics of Soils and Terrestrial Ecosystems, Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland
| | - Walid Sadok
- Agronomy and Plant Genetics, College of Food, Agricultural and Natural Resource Sciences, University of Minnesota, Twin Cities, MN, USA
| | - Andrea Carminati
- Physics of Soils and Terrestrial Ecosystems, Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland
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9
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Blonder BW, Aparecido LMT, Hultine KR, Lombardozzi D, Michaletz ST, Posch BC, Slot M, Winter K. Plant water use theory should incorporate hypotheses about extreme environments, population ecology, and community ecology. New Phytol 2023; 238:2271-2283. [PMID: 36751903 DOI: 10.1111/nph.18800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 01/30/2023] [Indexed: 05/19/2023]
Abstract
Plant water use theory has largely been developed within a plant-performance paradigm that conceptualizes water use in terms of value for carbon gain and that sits within a neoclassical economic framework. This theory works very well in many contexts but does not consider other values of water to plants that could impact their fitness. Here, we survey a range of alternative hypotheses for drivers of water use and stomatal regulation. These hypotheses are organized around relevance to extreme environments, population ecology, and community ecology. Most of these hypotheses are not yet empirically tested and some are controversial (e.g. requiring more agency and behavior than is commonly believed possible for plants). Some hypotheses, especially those focused around using water to avoid thermal stress, using water to promote reproduction instead of growth, and using water to hoard it, may be useful to incorporate into theory or to implement in Earth System Models.
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Affiliation(s)
- Benjamin Wong Blonder
- Department of Environmental Science, Policy, and Management, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Luiza Maria Teophilo Aparecido
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ, 85287, USA
- Department of Research, Conservation and Collections, Desert Botanical Garden, Phoenix, AZ, 85008, USA
| | - Kevin R Hultine
- Department of Research, Conservation and Collections, Desert Botanical Garden, Phoenix, AZ, 85008, USA
| | - Danica Lombardozzi
- Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO, 80305, USA
| | - Sean T Michaletz
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Bradley C Posch
- Department of Environmental Science, Policy, and Management, University of California Berkeley, Berkeley, CA, 94720, USA
- Department of Research, Conservation and Collections, Desert Botanical Garden, Phoenix, AZ, 85008, USA
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, 79409, USA
| | - Martijn Slot
- Smithsonian Tropical Research Institute, Balboa, Ancón, 0843-03092, Panama
| | - Klaus Winter
- Smithsonian Tropical Research Institute, Balboa, Ancón, 0843-03092, Panama
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Abdalla M, Schweiger AH, Berauer BJ, McAdam SAM, Ahmed MA. Constant hydraulic supply and ABA dynamics facilitate the trade-offs in water and carbon. Front Plant Sci 2023; 14:1140938. [PMID: 37008480 PMCID: PMC10064056 DOI: 10.3389/fpls.2023.1140938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 03/03/2023] [Indexed: 06/19/2023]
Abstract
Carbon-water trade-offs in plants are adjusted through stomatal regulation. Stomatal opening enables carbon uptake and plant growth, whereas plants circumvent drought by closing stomata. The specific effects of leaf position and age on stomatal behavior remain largely unknown, especially under edaphic and atmospheric drought. Here, we compared stomatal conductance (gs ) across the canopy of tomato during soil drying. We measured gas exchange, foliage ABA level and soil-plant hydraulics under increasing vapor pressure deficit (VPD). Our results indicate a strong effect of canopy position on stomatal behavior, especially under hydrated soil conditions and relatively low VPD. In wet soil (soil water potential > -50 kPa), upper canopy leaves had the highest gs (0.727 ± 0.154 mol m-2 s-1) and assimilation rate (A; 23.4 ± 3.9 µmol m-2 s-1) compared to the leaves at a medium height of the canopy (gs : 0.159 ± 0.060 mol m2 s-1; A: 15.9 ± 3.8 µmol m-2 s-1). Under increasing VPD (from 1.8 to 2.6 kPa), gs , A and transpiration were initially impacted by leaf position rather than leaf age. However, under high VPD (2.6 kPa), age effect outweighed position effect. The soil-leaf hydraulic conductance was similar in all leaves. Foliage ABA levels increased with rising VPD in mature leaves at medium height (217.56 ± 85 ng g-1 FW) compared to upper canopy leaves (85.36 ± 34 ng g-1 FW). Under soil drought (< -50 kPa), stomata closed in all leaves resulting in no differences in gs across the canopy. We conclude that constant hydraulic supply and ABA dynamics facilitate preferential stomatal behavior and carbon-water trade-offs across the canopy. These findings are fundamental in understanding variations within the canopy, which helps in engineering future crops, especially in the face of climate change.
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Affiliation(s)
- Mohanned Abdalla
- Department of Land, Air and Water Resources, University of California Davis, Davis, CA, United States
- Chair of Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
- Department of Horticulture, Faculty of Agriculture, University of Khartoum, Khartoum North, Sudan
- Chair of Soil-Root Interactions, TUM School of Life Science, Technical University of Munich, Freising, Germany
| | - Andreas H. Schweiger
- Institute of Landscape and Plant Ecology, Department of Plant Ecology, University of Hohenheim, Stuttgart, Germany
| | - Bernd J. Berauer
- Institute of Landscape and Plant Ecology, Department of Plant Ecology, University of Hohenheim, Stuttgart, Germany
| | - Scott A. M. McAdam
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, United States
| | - Mutez Ali Ahmed
- Chair of Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
- Chair of Soil-Root Interactions, TUM School of Life Science, Technical University of Munich, Freising, Germany
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11
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Cobo-Simón I, Maloof JN, Li R, Amini H, Méndez-Cea B, García-García I, Gómez-Garrido J, Esteve-Codina A, Dabad M, Alioto T, Wegrzyn JL, Seco JI, Linares JC, Gallego FJ. Contrasting transcriptomic patterns reveal a genomic basis for drought resilience in the relict fir Abies pinsapo Boiss. Tree Physiol 2023; 43:315-334. [PMID: 36210755 DOI: 10.1093/treephys/tpac115] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 10/05/2022] [Indexed: 06/16/2023]
Abstract
Climate change challenges the adaptive capacity of several forest tree species in the face of increasing drought and rising temperatures. Therefore, understanding the mechanistic connections between genetic diversity and drought resilience is highly valuable for conserving drought-sensitive forests. Nonetheless, the post-drought recovery in trees from a transcriptomic perspective has not yet been studied by comparing contrasting phenotypes. Here, experimental drought treatments, gas-exchange dynamics and transcriptomic analysis (RNA-seq) were performed in the relict and drought-sensitive fir Abies pinsapo Boiss. to identify gene expression differences over immediate (24 h) and extended drought (20 days). Post-drought responses were investigated to define resilient and sensitive phenotypes. Single nucleotide polymorphisms (SNPs) were also studied to characterize the genomic basis of A. pinsapo drought resilience. Weighted gene co-expression network analysis showed an activation of stomatal closing and an inhibition of plant growth-related genes during the immediate drought, consistent with an isohydric dynamic. During the extended drought, transcription factors, as well as cellular damage and homeostasis protection-related genes prevailed. Resilient individuals activate photosynthesis-related genes and inhibit aerial growth-related genes, suggesting a shifting shoot/root biomass allocation to improve water uptake and whole-plant carbon balance. About, 152 fixed SNPs were found between resilient and sensitive seedlings, which were mostly located in RNA-activity-related genes, including epigenetic regulation. Contrasting gene expression and SNPs were found between different post-drought resilience phenotypes for the first time in a forest tree, suggesting a transcriptomic and genomic basis for drought resilience. The obtained drought-related transcriptomic profile and drought-resilience candidate genes may guide conservation programs for this threatened tree species.
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Affiliation(s)
- Irene Cobo-Simón
- Dpto Sistemas Físicos, Químicos y Naturales, Univ. Pablo de Olavide, 41013 Sevilla, Spain
- Dpto Genética, Fisiología y Microbiología, Unidad de Genética, Facultad de CC Biológicas, Universidad Complutense de Madrid 28040, Spain
| | - Julin N Maloof
- University of California at Davis, Department of Plant Biology, Davis, CA 95616, USA
| | - Ruijuan Li
- University of California at Davis, Department of Plant Biology, Davis, CA 95616, USA
| | - Hajar Amini
- University of California at Davis, Department of Plant Biology, Davis, CA 95616, USA
| | - Belén Méndez-Cea
- Dpto Genética, Fisiología y Microbiología, Unidad de Genética, Facultad de CC Biológicas, Universidad Complutense de Madrid 28040, Spain
| | - Isabel García-García
- Dpto Genética, Fisiología y Microbiología, Unidad de Genética, Facultad de CC Biológicas, Universidad Complutense de Madrid 28040, Spain
| | - Jèssica Gómez-Garrido
- CNAG-CRG, Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona 08028, Spain
| | - Anna Esteve-Codina
- CNAG-CRG, Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona 08028, Spain
| | - Marc Dabad
- CNAG-CRG, Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona 08028, Spain
| | - Tyler Alioto
- CNAG-CRG, Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona 08028, Spain
| | - Jill L Wegrzyn
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA
| | - José Ignacio Seco
- Dpto Sistemas Físicos, Químicos y Naturales, Univ. Pablo de Olavide, 41013 Sevilla, Spain
| | - Juan Carlos Linares
- Dpto Sistemas Físicos, Químicos y Naturales, Univ. Pablo de Olavide, 41013 Sevilla, Spain
| | - Francisco Javier Gallego
- Dpto Genética, Fisiología y Microbiología, Unidad de Genética, Facultad de CC Biológicas, Universidad Complutense de Madrid 28040, Spain
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12
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Salvi AM, Gosetti SG, Smith DD, Adams MA, Givnish TJ, McCulloh KA. Hydroscapes, hydroscape plasticity and relationships to functional traits and mesophyll photosynthetic sensitivity to leaf water potential in Eucalyptus species. Plant Cell Environ 2022; 45:2573-2588. [PMID: 35706133 DOI: 10.1111/pce.14380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 06/06/2022] [Accepted: 06/13/2022] [Indexed: 06/15/2023]
Abstract
The isohydric-anisohydric continuum describes the relative stringency of stomatal control of leaf water potential (ψleaf ) during drought. Hydroscape area (HA)-the water potential landscape over which stomata regulate ψleaf -has emerged as a useful metric of the iso/anisohydric continuum because it is strongly linked to several hydraulic, photosynthetic and structural traits. Previous research on HA focused on broad ecological patterns involving several plant clades. Here we investigate the relationships between HA and climatic conditions and functional traits across ecologically diverse but closely related species while accounting for phylogeny. Across a macroclimatic moisture gradient, defined by the ratio of mean annual precipitation to mean annual pan evaporation (P/Ep ), HA decreased with increased P/Ep across 10 Eucalyptus species. Greater anisohydry reflects lower turgor loss points and greater hydraulic safety, mirroring global patterns. Larger HA coincides with mesophyll photosynthetic capacity that is more sensitive to ψleaf . Hydroscapes exhibit little plasticity in response to variation in water supply, and the extent of plasticity does not vary with P/Ep of native habitats. These findings strengthen the case that HA is a useful metric for characterizing drought tolerance and water-status regulation.
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Affiliation(s)
- Amanda M Salvi
- Department of Botany, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Sophia G Gosetti
- Department of Botany, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Duncan D Smith
- Department of Botany, University of Wisconsin-Madison, Madison, Wisconsin, USA
- School of Ecosystem and Forest Sciences, University of Melbourne, Creswick, Victoria, Australia
- Swinburne University of Technology, Hawthorn, Victoria, Australia
| | - Mark A Adams
- Swinburne University of Technology, Hawthorn, Victoria, Australia
| | - Thomas J Givnish
- Department of Botany, University of Wisconsin-Madison, Madison, Wisconsin, USA
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13
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Limousin JM, Roussel A, Rodríguez-Calcerrada J, Torres-Ruiz JM, Moreno M, Garcia de Jalon L, Ourcival JM, Simioni G, Cochard H, Martin-StPaul N. Drought acclimation of Quercus ilex leaves improves tolerance to moderate drought but not resistance to severe water stress. Plant Cell Environ 2022; 45:1967-1984. [PMID: 35394675 DOI: 10.1111/pce.14326] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 03/12/2022] [Accepted: 03/22/2022] [Indexed: 06/14/2023]
Abstract
Increasing temperature and drought can result in leaf dehydration and defoliation even in drought-adapted tree species such as the Mediterranean evergreen Quercus ilex L. The stomatal regulation of leaf water potential plays a central role in avoiding this phenomenon and is constrained by a suite of leaf traits including hydraulic conductance and vulnerability, hydraulic capacitance, minimum conductance to water vapour, osmotic potential and cell wall elasticity. We investigated whether the plasticity in these traits may improve leaf tolerance to drought in two long-term rainfall exclusion experiments in Mediterranean forests. Osmotic adjustment was observed to lower the water potential at turgor loss in the rainfall-exclusion treatments, thus suggesting a stomatal closure at more negative water potentials and a more anisohydric behaviour in drier conditions. Conversely, leaf hydraulic conductance and vulnerability did not exhibit any plasticity between treatments so the hydraulic safety margins were narrower in the rainfall-exclusion treatments. The sequence of leaf responses to seasonal drought and dehydration was conserved among treatments and sites but trees were more likely to suffer losses of turgor and hydraulic functioning in the rainfall-exclusion treatments. We conclude that leaf plasticity might help the trees to tolerate moderate drought but not to resist severe water stress.
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Affiliation(s)
| | - Amélie Roussel
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - Jesús Rodríguez-Calcerrada
- Departamento de Sistemas y Recursos Naturales, ETSI Montes, Forestal y del Medio Natural, Universidad Politécnica de Madrid Ciudad Universitaria, Madrid, Spain
| | | | - Myriam Moreno
- Unité Ecologie des Forêts Méditerranéennes (UR629), INRAE Avignon Cedex 9, Domaine Saint Paul, Site Agroparc, France
| | | | | | - Guillaume Simioni
- Unité Ecologie des Forêts Méditerranéennes (UR629), INRAE Avignon Cedex 9, Domaine Saint Paul, Site Agroparc, France
| | - Hervé Cochard
- PIAF, University Clermont-Auvergne, INRAE, Clermont-Ferrand, France
| | - Nicolas Martin-StPaul
- Unité Ecologie des Forêts Méditerranéennes (UR629), INRAE Avignon Cedex 9, Domaine Saint Paul, Site Agroparc, France
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14
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Wang J, Fu X, Zhang S, Chen G, Li S, Shangguan T, Zheng Y, Xu F, Chen ZH, Xu S. Evolutionary and Regulatory Pattern Analysis of Soybean Ca 2+ ATPases for Abiotic Stress Tolerance. Front Plant Sci 2022; 13:898256. [PMID: 35665149 PMCID: PMC9161174 DOI: 10.3389/fpls.2022.898256] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 05/02/2022] [Indexed: 06/15/2023]
Abstract
P2-type Ca2+ ATPases are responsible for cellular Ca2+ transport, which plays an important role in plant development and tolerance to biotic and abiotic stresses. However, the role of P2-type Ca2+ ATPases in stress response and stomatal regulation is still elusive in soybean. In this study, a total of 12 P2-type Ca2+ ATPases genes (GmACAs and GmECAs) were identified from the genome of Glycine max. We analyzed the evolutionary relationship, conserved motif, functional domain, gene structure and location, and promoter elements of the family. Chlorophyll fluorescence imaging analysis showed that vegetable soybean leaves are damaged to different extents under salt, drought, cold, and shade stresses. Real-time quantitative PCR (RT-qPCR) analysis demonstrated that most of the GmACAs and GmECAs are up-regulated after drought, cold, and NaCl treatment, but are down-regulated after shading stress. Microscopic observation showed that different stresses caused significant stomatal closure. Spatial location and temporal expression analysis suggested that GmACA8, GmACA9, GmACA10, GmACA12, GmACA13, and GmACA11 might promote stomatal closure under drought, cold, and salt stress. GmECA1 might regulate stomatal closure in shading stress. GmACA1 and GmECA3 might have a negative function on cold stress. The results laid an important foundation for further study on the function of P2-type Ca2+ ATPase genes GmACAs and GmECAs for breeding abiotic stress-tolerant vegetable soybean.
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Affiliation(s)
- Jian Wang
- Central Laboratory, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Xujun Fu
- Central Laboratory, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Sheng Zhang
- Taizhou Seed Administration Station, Taizhou, China
| | - Guang Chen
- Central Laboratory, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Sujuan Li
- Central Laboratory, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Tengwei Shangguan
- College of Agriculture and Food Science, Zhejiang Agriculture and Forestry University, Hangzhou, China
| | - Yuanting Zheng
- Central Laboratory, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Fei Xu
- Central Laboratory, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Zhong-Hua Chen
- School of Science, Western Sydney University, Penrith, NSW, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Shengchun Xu
- Central Laboratory, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
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15
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Zhao Z, Fan J, Gao YG, Wang Z, Yang P, Liang Y, Opiyo S, Xia Y. Arabidopsis Plasma Membrane ATPase AHA5 Is Negatively Involved in PAMP-Triggered Immunity. Int J Mol Sci 2022; 23:3857. [PMID: 35409217 DOI: 10.3390/ijms23073857] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 03/20/2022] [Accepted: 03/29/2022] [Indexed: 11/17/2022] Open
Abstract
Plants evolve a prompt and robust immune system to defend themselves against pathogen infections. Pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) is the first battle layer activated upon the PAMP’s perception, which leads to multiple defense responses. The plasma membrane (PM) H+-ATPases are the primary ion pumps to create and maintain the cellular membrane potential that is critical for various essential biological processes, including plant growth, development, and defense. This study discovered that the PM H+-ATPase AHA5 is negatively involved in Arabidopsis PTI against the virulent pathogen Pseudomonas syringae pvr. tomato (Pto) DC3000 infection. The aha5 mutant plants caused the reduced stomata opening upon the Pto infection, which was associated with the salicylic acid (SA) pathway. In addition, the aha5 mutant plants caused the increased levels of callose deposition, defense-related gene expression, and SA accumulation. Our results also indicate that the PM H+-ATPase activity of AHA5 probably mediates the coupling of H2O2 generation and the apoplast alkalization in PTI responses. Moreover, AHA5 was found to interact with a vital defense regulator, RPM1-interacting protein 4 (RIN4), in vitro and in vivo, which might also be critical for its function in PTI. In summary, our studies show that AHA5 functions as a novel and critical component that is negatively involved in PTI by coordinating different defense responses during the Arabidopsis–Pto DC3000 interaction.
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Hunt L, Fuksa M, Klem K, Lhotáková Z, Oravec M, Urban O, Albrechtová J. Barley Genotypes Vary in Stomatal Responsiveness to Light and CO 2 Conditions. Plants (Basel) 2021; 10:plants10112533. [PMID: 34834896 PMCID: PMC8625854 DOI: 10.3390/plants10112533] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/16/2021] [Accepted: 11/18/2021] [Indexed: 05/03/2023]
Abstract
Changes in stomatal conductance and density allow plants to acclimate to changing environmental conditions. In the present paper, the influence of atmospheric CO2 concentration and light intensity on stomata were investigated for two barley genotypes-Barke and Bojos, differing in their sensitivity to oxidative stress and phenolic acid profiles. A novel approach for stomatal density analysis was used-a pair of convolution neural networks were developed to automatically identify and count stomata on epidermal micrographs. Stomatal density in barley was influenced by genotype, as well as by light and CO2 conditions. Low CO2 conditions resulted in increased stomatal density, although differences between ambient and elevated CO2 were not significant. High light intensity increased stomatal density compared to low light intensity in both barley varieties and all CO2 treatments. Changes in stomatal conductance were also measured alongside the accumulation of pentoses, hexoses, disaccharides, and abscisic acid detected by liquid chromatography coupled with mass spectrometry. High light increased the accumulation of all sugars and reduced abscisic acid levels. Abscisic acid was influenced by all factors-light, CO2, and genotype-in combination. Differences were discovered between the two barley varieties: oxidative stress sensitive Barke demonstrated higher stomatal density, but lower conductance and better water use efficiency (WUE) than oxidative stress resistant Bojos at saturating light intensity. Barke also showed greater variability between treatments in measurements of stomatal density, sugar accumulation, and abscisic levels, implying that it may be more responsive to environmental drivers influencing water relations in the plant.
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Affiliation(s)
- Lena Hunt
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Viničná 5, 12844 Praha, Czech Republic; (L.H.); (M.F.); (Z.L.)
| | - Michal Fuksa
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Viničná 5, 12844 Praha, Czech Republic; (L.H.); (M.F.); (Z.L.)
| | - Karel Klem
- Global Change Research Institute, Czech Academy of Sciences, Bělidla 4a, 60300 Brno, Czech Republic; (K.K.); (M.O.); (O.U.)
| | - Zuzana Lhotáková
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Viničná 5, 12844 Praha, Czech Republic; (L.H.); (M.F.); (Z.L.)
| | - Michal Oravec
- Global Change Research Institute, Czech Academy of Sciences, Bělidla 4a, 60300 Brno, Czech Republic; (K.K.); (M.O.); (O.U.)
| | - Otmar Urban
- Global Change Research Institute, Czech Academy of Sciences, Bělidla 4a, 60300 Brno, Czech Republic; (K.K.); (M.O.); (O.U.)
| | - Jana Albrechtová
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Viničná 5, 12844 Praha, Czech Republic; (L.H.); (M.F.); (Z.L.)
- Correspondence: ; Tel.: +420-221-95-1959
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17
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Chen Z, Zhang Y, Yuan W, Zhu S, Pan R, Wan X, Liu S. Coordinated variation in stem and leaf functional traits of temperate broadleaf tree species in the isohydric-anisohydric spectrum. Tree Physiol 2021; 41:1601-1610. [PMID: 33693879 DOI: 10.1093/treephys/tpab028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 02/08/2021] [Indexed: 06/12/2023]
Abstract
Stomatal regulation serves as an important strategy for plants to adapt to drought. However, the understanding of how complexes of plant-functional traits vary along the continuum from isohydry to anisohydry remains insufficient. In this study, we investigated a proxy of the degree of iso/anisohydry-the water potential at stomatal closure-and a series of functional traits of leaves and branches in 20 temperate broadleaf species planted in an arid limestone habitat in northern China. The results showed that the water potential at stomatal closure was significantly correlated with many functional traits. At the anisohydric end of the spectrum, species had a higher leaf carbon content and vein density, a greater stomatal length, a thicker lower leaf epidermis, higher embolism resistance, higher wood density, a greater Huber value, a greater ratio of fiber wall thickness to xylem lumen diameter, a larger proportion of total fiber wall area to xylem cross-sectional area, a lower water potential at the turgor loss point (TLP), a smaller relative water content at the TLP, a lower osmotic potential at full turgor and a smaller specific leaf area. It is concluded that a continuum of coordination and trade-offs among co-evolved anatomical and physiological traits gives rise to the spectrum from isohydry to anisohydry spanned by the 20 tree species, and the anisohydric species showed stronger stress resistance, with greater investment in stems and leaves than the isohydric species to maintain stomatal opening under drought conditions.
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Affiliation(s)
- Zhicheng Chen
- Research Institute of Forestry New Technology, Chinese Academy of Forestry, Beijing 100091, China
| | - Yongtao Zhang
- Mountain Tai Forest Ecosystem Research Station of National Forestry and Grassland Administration, Forestry College of Shandong Agricultural University, Taian 271018, China
| | - Weijie Yuan
- Experimental Center of Forestry in North China, Chinese Academy of Forestry, Beijing 102300, China
| | - Shidan Zhu
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning 530004, China
| | - Ruihua Pan
- School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China
| | - Xianchong Wan
- Research Institute of Forestry New Technology, Chinese Academy of Forestry, Beijing 100091, China
| | - Shirong Liu
- Key laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091, China
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18
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Álvarez-Maldini C, Acevedo M, Pinto M. Hydroscapes: A Useful Metric for Distinguishing Iso-/Anisohydric Behavior in Almond Cultivars. Plants (Basel) 2021; 10:plants10061249. [PMID: 34205343 PMCID: PMC8233807 DOI: 10.3390/plants10061249] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 05/07/2021] [Accepted: 05/10/2021] [Indexed: 06/13/2023]
Abstract
As a consequence of climate change, water scarcity has increased the use of the iso-/anisohydric concept with the aim of identifying anisohydric or drought-tolerant genotypes. Recently, Meinzer and colleagues developed a metric for discriminating between iso- and anisohydric behavior called the hydroscape, which describes a range in which stomata control leaf water potential (Ψ) with decreasing water availability, and it is linked to several water-regulation and drought-tolerance traits. Thus, our objective was to test the usefulness of the hydroscape in discriminating between iso- and anisohydric Prunus dulcis cultivars, a species that is widely cultivated in Mediterranean central Chile due to its ability to withstand water stress. Through a pot desiccation experiment, we determined that the hydroscape was able to discriminate between two contrasting Prunus cultivars; the more anisohydric cultivar had a hydroscape 4.5 times greater than that of the other cultivar, and the hydroscape correlated with other metrics of plant water-use strategies, such as the maximum range of daily Ψ variation and the Ψ at stomatal closure. Moreover, the photosynthesis rates were also differently affected between cultivars. The more isohydric cultivar, which had a smaller hydroscape, displayed a steeper photosynthesis reduction at progressively lower midday Ψ. This methodology could be further used to identify drought-tolerant anisohydric Prunus cultivars.
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Affiliation(s)
- Carolina Álvarez-Maldini
- Instituto Ciencias Agro-alimentarias, Animales y Ambientales (ICA3), Campus Colchagua, Universidad de O’Higgins, San Fernando 2840440, Chile;
| | - Manuel Acevedo
- Instituto Forestal, Centro Tecnológico de la Planta Forestal, San Pedro de la Paz 7770223, Chile;
| | - Manuel Pinto
- Instituto Ciencias Agro-alimentarias, Animales y Ambientales (ICA3), Campus Colchagua, Universidad de O’Higgins, San Fernando 2840440, Chile;
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Sorek Y, Greenstein S, Netzer Y, Shtein I, Jansen S, Hochberg U. An increase in xylem embolism resistance of grapevine leaves during the growing season is coordinated with stomatal regulation, turgor loss point and intervessel pit membranes. New Phytol 2021; 229:1955-1969. [PMID: 33098088 DOI: 10.1111/nph.17025] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 10/02/2020] [Indexed: 05/27/2023]
Abstract
Although xylem embolism resistance is traditionally considered as static, we hypothesized that in grapevine (Vitis vinifera) leaf xylem becomes more embolism-resistant over the growing season. We evaluated xylem architecture, turgor loss point (ΨTLP ) and water potentials leading to 25% of maximal stomatal conductance (gs25 ) or 50% embolism in the leaf xylem (P50 ) in three irrigation treatments and at three time points during the growing season, while separating the effects of leaf age and time of season. Hydraulic traits acclimated over the growing season in a coordinated manner. Without irrigation, ΨTLP , gs25 , and P50 decreased between late May and late August by 0.95, 0.77 and 0.71 MPa, respectively. A seasonal shift in P50 occurred even in mature leaves, while irrigation had only a mild effect (< 0.2 MPa) on P50 . Vessel size and pit membrane thickness were also seasonally dynamic, providing a plausible explanation for the shift in P50 . Our findings provide clear evidence that grapevines can modify their hydraulic traits along a growing season to allow lower xylem water potential, without compromising gas exchange, leaf turgor or xylem integrity. Seasonal changes should be considered when modeling ecosystem vulnerability to drought or comparing datasets acquired at different phenological stages.
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Affiliation(s)
- Yonatan Sorek
- Institute of Soil, Water and Environmental Science, Volcani Center, Agricultural Research Organization, PO Box 6, Bet-Dagan, 50250, Israel
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100, Israel
| | - Smadar Greenstein
- Institute of Soil, Water and Environmental Science, Volcani Center, Agricultural Research Organization, PO Box 6, Bet-Dagan, 50250, Israel
| | - Yishai Netzer
- Department of Chemical engineering, Ariel University, Ariel, 40700, Israel
- Agriculture and Oenology Department, Eastern R&D Center, Ariel, 40700, Israel
| | - Ilana Shtein
- Agriculture and Oenology Department, Eastern R&D Center, Ariel, 40700, Israel
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, Ulm, D-89081, Germany
| | - Uri Hochberg
- Institute of Soil, Water and Environmental Science, Volcani Center, Agricultural Research Organization, PO Box 6, Bet-Dagan, 50250, Israel
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20
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Perera-Castro AV, Nadal M, Flexas J. What drives photosynthesis during desiccation? Mosses and other outliers from the photosynthesis-elasticity trade-off. J Exp Bot 2020; 71:6460-6470. [PMID: 32686831 DOI: 10.1093/jxb/eraa328] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 07/15/2020] [Indexed: 06/11/2023]
Abstract
In vascular plants, more rigid leaves have been linked to lower photosynthetic capacity, associated with low CO2 diffusion across the mesophyll, indirectly resulting in a trade-off between photosynthetic capacity (An) and bulk modulus of elasticity (ε). However, we evaluated mosses, liverworts, and Chara sp., plus some lycophytes and ferns, and found that they behaved as clear outliers of the An-ε relationship. Despite this finding, when vascular and non-vascular plants were plotted together, ε still linearly determined the cessation of net photosynthesis during desiccation both in species with stomata (either actively or hydro-passively regulated) and in species lacking stomata, and regardless of their leaf structure. The latter result challenges our current view of photosynthetic responses to desiccation and/or water stress. Structural features and hydric strategy are discussed as possible explanations for the deviation of these species from the An-ε trade-off, as well as for the general linear dependency between ε and the full cessation of An during desiccation.
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Affiliation(s)
- Alicia V Perera-Castro
- Research Group on Plant Biology under Mediterranean Conditions. Departament de Biologia, Universitat de les Illes Balears, INAGEA Carretera de Valldemossa Km 7.5, Palma de Mallorca, Illes Balears, Spain
| | - Miquel Nadal
- Research Group on Plant Biology under Mediterranean Conditions. Departament de Biologia, Universitat de les Illes Balears, INAGEA Carretera de Valldemossa Km 7.5, Palma de Mallorca, Illes Balears, Spain
| | - Jaume Flexas
- Research Group on Plant Biology under Mediterranean Conditions. Departament de Biologia, Universitat de les Illes Balears, INAGEA Carretera de Valldemossa Km 7.5, Palma de Mallorca, Illes Balears, Spain
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21
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Barnaby JY, Kim J, Devi MJ, Fleisher DH, Tucker ML, Reddy VR, Sicher RC. Varying Atmospheric CO 2 Mediates the Cold-Induced CBF-Dependent Signaling Pathway and Freezing Tolerance in Arabidopsis. Int J Mol Sci 2020; 21:ijms21207616. [PMID: 33076265 PMCID: PMC7593905 DOI: 10.3390/ijms21207616] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 10/12/2020] [Accepted: 10/13/2020] [Indexed: 11/16/2022] Open
Abstract
Changes in the stomatal aperture in response to CO2 levels allow plants to manage water usage, optimize CO2 uptake and adjust to environmental stimuli. The current study reports that sub-ambient CO2 up-regulated the low temperature induction of the C-repeat Binding Factor (CBF)-dependent cold signaling pathway in Arabidopsis (Arabidopsis thaliana) and the opposite occurred in response to supra-ambient CO2. Accordingly, cold induction of various downstream cold-responsive genes was modified by CO2 treatments and expression changes were either partially or fully CBF-dependent. Changes in electrolyte leakage during freezing tests were correlated with CO2′s effects on CBF expression. Cold treatments were also performed on Arabidopsis mutants with altered stomatal responses to CO2, i.e., high leaf temperature 1-2 (ht1-2, CO2 hypersensitive) and β-carbonic anhydrase 1 and 4 (ca1ca4, CO2 insensitive). The cold-induced expression of CBF and downstream CBF target genes plus freezing tolerance of ht1-2 was consistently less than that for Col-0, suggesting that HT1 is a positive modulator of cold signaling. The ca1ca4 mutant had diminished CBF expression during cold treatment but the downstream expression of cold-responsive genes was either similar to or greater than that of Col-0. This finding suggested that βCA1/4 modulates the expression of certain cold-responsive genes in a CBF-independent manner. Stomatal conductance measurements demonstrated that low temperatures overrode low CO2-induced stomatal opening and this process was delayed in the cold tolerant mutant, ca1ca4, compared to the cold sensitive mutant, ht1-2. The similar stomatal responses were evident from freezing tolerant line, Ox-CBF, overexpression of CBF3, compared to wild-type ecotype Ws-2. Together, these results indicate that CO2 signaling in stomata and CBF-mediated cold signaling work coordinately in Arabidopsis to manage abiotic stress.
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Affiliation(s)
- Jinyoung Y. Barnaby
- Adaptive Cropping Systems Laboratory, Agricultural Research Service, USDA, Building 001, 10300 Baltimore Ave., Beltsville, MD 20705, USA; (M.J.D.); (D.H.F.); (V.R.R.); (R.C.S.)
- Dale Bumpers National Rice Research Center, Agricultural Research Service, USDA, Building 001, 10300 Baltimore Ave., Beltsville, MD 20705, USA
- Correspondence: ; Tel.:+1-301-504-8436
| | - Joonyup Kim
- Soybean Genomics and Improvement Laboratory, Agricultural Research Service, USDA, Building 006, 10300 Baltimore Ave., Beltsville, MD 20705, USA; (J.K.); (M.L.T.)
| | - Mura Jyostna Devi
- Adaptive Cropping Systems Laboratory, Agricultural Research Service, USDA, Building 001, 10300 Baltimore Ave., Beltsville, MD 20705, USA; (M.J.D.); (D.H.F.); (V.R.R.); (R.C.S.)
| | - David H. Fleisher
- Adaptive Cropping Systems Laboratory, Agricultural Research Service, USDA, Building 001, 10300 Baltimore Ave., Beltsville, MD 20705, USA; (M.J.D.); (D.H.F.); (V.R.R.); (R.C.S.)
| | - Mark L. Tucker
- Soybean Genomics and Improvement Laboratory, Agricultural Research Service, USDA, Building 006, 10300 Baltimore Ave., Beltsville, MD 20705, USA; (J.K.); (M.L.T.)
| | - Vangimalla R. Reddy
- Adaptive Cropping Systems Laboratory, Agricultural Research Service, USDA, Building 001, 10300 Baltimore Ave., Beltsville, MD 20705, USA; (M.J.D.); (D.H.F.); (V.R.R.); (R.C.S.)
| | - Richard C. Sicher
- Adaptive Cropping Systems Laboratory, Agricultural Research Service, USDA, Building 001, 10300 Baltimore Ave., Beltsville, MD 20705, USA; (M.J.D.); (D.H.F.); (V.R.R.); (R.C.S.)
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22
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Johansson KSL, El-Soda M, Pagel E, Meyer RC, Tõldsepp K, Nilsson AK, Brosché M, Kollist H, Uddling J, Andersson MX. Genetic controls of short- and long-term stomatal CO2 responses in Arabidopsis thaliana. Ann Bot 2020; 126:179-190. [PMID: 32296835 PMCID: PMC7304471 DOI: 10.1093/aob/mcaa065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 04/09/2020] [Indexed: 05/14/2023]
Abstract
BACKGROUND AND AIMS The stomatal conductance (gs) of most plant species decreases in response to elevated atmospheric CO2 concentration. This response could have a significant impact on plant water use in a future climate. However, the regulation of the CO2-induced stomatal closure response is not fully understood. Moreover, the potential genetic links between short-term (within minutes to hours) and long-term (within weeks to months) responses of gs to increased atmospheric CO2 have not been explored. METHODS We used Arabidopsis thaliana recombinant inbred lines originating from accessions Col-0 (strong CO2 response) and C24 (weak CO2 response) to study short- and long-term controls of gs. Quantitative trait locus (QTL) mapping was used to identify loci controlling short- and long-term gs responses to elevated CO2, as well as other stomata-related traits. KEY RESULTS Short- and long-term stomatal responses to elevated CO2 were significantly correlated. Both short- and long-term responses were associated with a QTL at the end of chromosome 2. The location of this QTL was confirmed using near-isogenic lines and it was fine-mapped to a 410-kb region. The QTL did not correspond to any known gene involved in stomatal closure and had no effect on the responsiveness to abscisic acid. Additionally, we identified numerous other loci associated with stomatal regulation. CONCLUSIONS We identified and confirmed the effect of a strong QTL corresponding to a yet unknown regulator of stomatal closure in response to elevated CO2 concentration. The correlation between short- and long-term stomatal CO2 responses and the genetic link between these traits highlight the importance of understanding guard cell CO2 signalling to predict and manipulate plant water use in a world with increasing atmospheric CO2 concentration. This study demonstrates the power of using natural variation to unravel the genetic regulation of complex traits.
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Affiliation(s)
- Karin S L Johansson
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
- Institute of Technology, University of Tartu, Tartu, Estonia
| | - Mohamed El-Soda
- Department of Genetics, Faculty of Agriculture, Cairo University, Cairo, Egypt
| | - Ellen Pagel
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Rhonda C Meyer
- Department of Molecular Genetics, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Seeland, Germany
| | - Kadri Tõldsepp
- Institute of Technology, University of Tartu, Tartu, Estonia
| | - Anders K Nilsson
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Mikael Brosché
- Institute of Technology, University of Tartu, Tartu, Estonia
- Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Hannes Kollist
- Institute of Technology, University of Tartu, Tartu, Estonia
| | - Johan Uddling
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Mats X Andersson
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
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23
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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: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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24
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Leonhardt N, Divol F, Chiarenza S, Deschamps S, Renaud J, Giacalone C, Nussaume L, Berthomé R, Péret B. Tissue-specific inactivation by cytosine deaminase/uracil phosphoribosyl transferase as a tool to study plant biology. Plant J 2020; 101:731-741. [PMID: 31625644 DOI: 10.1111/tpj.14569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 09/03/2019] [Accepted: 10/02/2019] [Indexed: 06/10/2023]
Abstract
Recent advances in the study of plant developmental and physiological responses have benefited from tissue-specific approaches, revealing the role of some cell types in these processes. Such approaches have relied on the inactivation of target cells using either toxic compounds or deleterious genes; however, both tissue-specific and truly inducible tools are lacking in order to precisely target a developmental window or specific growth response. We engineered the yeast fluorocytosine deaminase (FCY1) gene by creating a fusion with the bacterial uracil phosphoribosyl transferase (UPP) gene. The recombinant protein converts the precursor 5-fluorocytosine (5-FC) into 5-fluorouracyl, a drug used in the treatment of a range of cancers, which triggers DNA and RNA damage. We expressed the FCY-UPP gene construct in specific cell types using enhancer trap lines and promoters, demonstrating that this marker acts in a cell-autonomous manner. We also showed that it can inactivate slow developmental processes like lateral root formation by targeting pericycle cells. It also revealed a role for the lateral root cap and the epidermis in controlling root growth, a faster response. The 5-FC precursor acts systemically, as demonstrated by its ability to inhibit stomatal movements when supplied to the roots in combination with a guard cell-specific promoter. Finally, we demonstrate that the tissular inactivation is reversible, and can therefore be used to synchronize plant responses or to determine cell type-specific functions during different developmental stages. This tool will greatly enhance our capacity to understand the respective role of each cell type in plant physiology and development.
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Affiliation(s)
- Nathalie Leonhardt
- UMR7265, Laboratoire de Biologie du Développement des Plantes, Service de Biologie Végétale et de Microbiologie Environnementales, Institut de Biologie Environnementale et Biotechnologie, CNRS-CEA-Université Aix-Marseille Saint-Paul-lez-Durance, Saint Paul les Durance Cedex, France
| | - Fanchon Divol
- BPMP, Univ Montpellier, CNRS, INRA, SupAgro, Montpellier, France
| | - Serge Chiarenza
- UMR7265, Laboratoire de Biologie du Développement des Plantes, Service de Biologie Végétale et de Microbiologie Environnementales, Institut de Biologie Environnementale et Biotechnologie, CNRS-CEA-Université Aix-Marseille Saint-Paul-lez-Durance, Saint Paul les Durance Cedex, France
| | - Sabrina Deschamps
- UMR7265, Laboratoire de Biologie du Développement des Plantes, Service de Biologie Végétale et de Microbiologie Environnementales, Institut de Biologie Environnementale et Biotechnologie, CNRS-CEA-Université Aix-Marseille Saint-Paul-lez-Durance, Saint Paul les Durance Cedex, France
| | - Jeanne Renaud
- UMR7265, Laboratoire de Biologie du Développement des Plantes, Service de Biologie Végétale et de Microbiologie Environnementales, Institut de Biologie Environnementale et Biotechnologie, CNRS-CEA-Université Aix-Marseille Saint-Paul-lez-Durance, Saint Paul les Durance Cedex, France
| | - Cécile Giacalone
- UMR7265, Laboratoire de Biologie du Développement des Plantes, Service de Biologie Végétale et de Microbiologie Environnementales, Institut de Biologie Environnementale et Biotechnologie, CNRS-CEA-Université Aix-Marseille Saint-Paul-lez-Durance, Saint Paul les Durance Cedex, France
| | - Laurent Nussaume
- UMR7265, Laboratoire de Biologie du Développement des Plantes, Service de Biologie Végétale et de Microbiologie Environnementales, Institut de Biologie Environnementale et Biotechnologie, CNRS-CEA-Université Aix-Marseille Saint-Paul-lez-Durance, Saint Paul les Durance Cedex, France
| | - Richard Berthomé
- LIPM, Université de Toulouse, INRA, CNRS, UPS, Castanet-Tolosan, France
| | - Benjamin Péret
- BPMP, Univ Montpellier, CNRS, INRA, SupAgro, Montpellier, France
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25
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Kumar M, Kesawat MS, Ali A, Lee SC, Gill SS, Kim HU. Integration of Abscisic Acid Signaling with Other Signaling Pathways in Plant Stress Responses and Development. Plants (Basel) 2019; 8:E592. [PMID: 31835863 PMCID: PMC6963649 DOI: 10.3390/plants8120592] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Revised: 11/26/2019] [Accepted: 12/10/2019] [Indexed: 12/30/2022]
Abstract
Plants are immobile and, to overcome harsh environmental conditions such as drought, salt, and cold, they have evolved complex signaling pathways. Abscisic acid (ABA), an isoprenoid phytohormone, is a critical signaling mediator that regulates diverse biological processes in various organisms. Significant progress has been made in the determination and characterization of key ABA-mediated molecular factors involved in different stress responses, including stomatal closure and developmental processes, such as seed germination and bud dormancy. Since ABA signaling is a complex signaling network that integrates with other signaling pathways, the dissection of its intricate regulatory network is necessary to understand the function of essential regulatory genes involved in ABA signaling. In the present review, we focus on two aspects of ABA signaling. First, we examine the perception of the stress signal (abiotic and biotic) and the response network of ABA signaling components that transduce the signal to the downstream pathway to respond to stress tolerance, regulation of stomata, and ABA signaling component ubiquitination. Second, ABA signaling in plant development processes, such as lateral root growth regulation, seed germination, and flowering time regulation is investigated. Examining such diverse signal integration dynamics could enhance our understanding of the underlying genetic, biochemical, and molecular mechanisms of ABA signaling networks in plants.
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Affiliation(s)
- Manu Kumar
- Department of Bioindustry and Bioresource Engineering, Plant Engineering Research Institute, Sejong University, Seoul 05006, Korea
| | | | - Asjad Ali
- Southern Cross Plant Science, Southern Cross University, East Lismore NSW 2480, Australia;
| | | | - Sarvajeet Singh Gill
- Stress Physiology and Molecular Biology Lab, Centre for Biotechnology, MD University, Rohtak 124001, India;
| | - Hyun Uk Kim
- Department of Bioindustry and Bioresource Engineering, Plant Engineering Research Institute, Sejong University, Seoul 05006, Korea
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26
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Holanda AER, Souza BC, Carvalho ECD, Oliveira RS, Martins FR, Muniz CR, Costa RC, Soares AA. How do leaf wetting events affect gas exchange and leaf lifespan of plants from seasonally dry tropical vegetation? Plant Biol (Stuttg) 2019; 21:1097-1109. [PMID: 31251437 DOI: 10.1111/plb.13023] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 06/25/2019] [Indexed: 06/09/2023]
Abstract
Foliar uptake of dew is likely an important mechanism of water acquisition for plants from tropical dry environments. However, there is still limited experimental evidence describing the anatomical pathways involved in this process and the effects of this water subsidy on the maintenance of gas exchange and leaf lifespan of species from seasonally dry tropical vegetation such as the Brazilian caatinga. We performed scanning electron, bright-field and confocal microscopic analyses and used apoplastic tracers to examine the foliar water uptake (FWU) routes in four woody species with different foliar phenology and widely distributed in the caatinga. Leaves of plants subjected to water stress were exposed to dew simulation to evaluate the effects of the FWU on leaf water potentials, gas exchange and leaf lifespan. All species absorbed water through their leaf cuticles and/or peltate trichomes but FWU capacity differed among species. Leaf wetting by dew increased leaf lifespan duration up to 36 days compared to plants in the drought treatment. A positive effect on leaf gas exchange and new leaf production was only observed in the anisohydric and evergreen species. We showed that leaf wetting by dew is relevant for the physiology and leaf lifespan of plants from seasonally dry tropical vegetation, especially for evergreen species.
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Affiliation(s)
- A E R Holanda
- Graduate Program in Ecology and Natural Resources, Department of Biology, Federal University of Ceará, Fortaleza, Brazil
| | - B C Souza
- Graduate Program in Ecology and Natural Resources, Department of Biology, Federal University of Ceará, Fortaleza, Brazil
| | - E C D Carvalho
- Graduate Program in Ecology and Natural Resources, Department of Biology, Federal University of Ceará, Fortaleza, Brazil
| | - R S Oliveira
- Department of Plant Biology, Institute of Biology, University of Campinas - UNICAMP, Campinas, Brazil
| | - F R Martins
- Department of Plant Biology, Institute of Biology, University of Campinas - UNICAMP, Campinas, Brazil
| | - C R Muniz
- Embrapa Tropical Agroindustry, Fortaleza, Brazil
| | - R C Costa
- Department of Biology, Federal University of Ceará, Fortaleza, Brazil
| | - A A Soares
- Department of Biology, Federal University of Ceará, Fortaleza, Brazil
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27
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Chen Z, Li S, Luan J, Zhang Y, Zhu S, Wan X, Liu S. Prediction of temperate broadleaf tree species mortality in arid limestone habitats with stomatal safety margins. Tree Physiol 2019; 39:1428-1437. [PMID: 30977822 DOI: 10.1093/treephys/tpz045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 03/24/2019] [Accepted: 04/04/2019] [Indexed: 06/09/2023]
Abstract
A growing body of evidence highlights the occurrence of increased widespread tree mortality during climate change-associated severe droughts; however, in situ long-term drought experiments with multispecies communities for the prediction of tree mortality and exploration of related mechanisms are rather limited in natural environments. We conducted a 7-year afforestation trial with 20 drought-resistant broadleaf tree species in an arid limestone habitat in northern China, where the species displayed a broad range of survival rates. The stomatal and xylem hydraulic traits of all the species were measured. We found that species' stomatal closure points were strongly related to their xylem embolism resistance and xylem minimum water potential but not to their survival rates. Hydraulic failure of the vascular system appeared to be the main cause of tree mortality, and the stomatal safety margin was a better predictor of tree mortality than the traditionally considered xylem embolism resistance and hydraulic safety margin. We recommend the stomatal safety margin as the indicator for predicting drought-induced tree mortality and for selecting tree species in future forest restorations in arid regions.
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Affiliation(s)
- Zhicheng Chen
- Research Institute of Forestry New Technology, Chinese Academy of Forestry, Beijing, China
| | - Shan Li
- Department of Wood Anatomy and Utilization, Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing, China
| | - Junwei Luan
- Institute for Resources and Environment, International Centre for Bamboo and Rattan, Key Laboratory of Bamboo and Rattan Science and Technology, National Forestry and Grassland Administration, Beijing, China
- Department of Natural Resource Sciences, Macdonald Campus, McGill University, Lakeshore Road, Ste-Anne-de-Bellevue, Quebec, Canada
| | - Yongtao Zhang
- Mountain Tai Forest Ecosystem Research Station of National Forestry and Grassland Administration, Forestry College of Shandong Agricultural University, Taian, China
| | - Shidan Zhu
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, China
| | - Xianchong Wan
- Research Institute of Forestry New Technology, Chinese Academy of Forestry, Beijing, China
| | - Shirong Liu
- Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing, China
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28
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Fu X, Meinzer FC, Woodruff DR, Liu YY, Smith DD, McCulloh KA, Howard AR. Coordination and trade-offs between leaf and stem hydraulic traits and stomatal regulation along a spectrum of isohydry to anisohydry. Plant Cell Environ 2019; 42:2245-2258. [PMID: 30820970 DOI: 10.1111/pce.13543] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 02/22/2019] [Accepted: 02/24/2019] [Indexed: 06/09/2023]
Abstract
The degree of plant iso/anisohydry, a widely used framework for classifying species-specific hydraulic strategies, integrates multiple components of the whole-plant hydraulic pathway. However, little is known about how it associates with coordination of functional and structural traits within and across different organs. We examined stem and leaf hydraulic capacitance and conductivity/conductance, stem xylem anatomical features, stomatal regulation of daily minimum leaf and stem water potential (Ψ), and the kinetics of stomatal responses to vapour pressure deficit (VPD) in six diverse woody species differing markedly in their degree of iso/anisohydry. At the stem level, more anisohydric species had higher wood density and lower native capacitance and conductivity. Like stems, leaves of more anisohydric species had lower hydraulic conductance; however, unlike stems, their leaves had higher native capacitance at their daily minimum values of leaf Ψ. Moreover, rates of VPD-induced stomatal closure were related to intrinsic rather than native leaf capacitance and were not associated with species' degree of iso/anisohydry. Our results suggest a trade-off between hydraulic storage and efficiency in the leaf, but a coordination between hydraulic storage and efficiency in the stem along a spectrum of plant iso/anisohydry.
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Affiliation(s)
- Xiaoli Fu
- Qianyanzhou Ecological Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- Zhongke-Ji'an Institute for Eco-Environmental Sciences, Ji'an, China
| | | | - David R Woodruff
- USDA Forest Service, Pacific Northwest Research Station, Corvallis, Oregon
| | - Yan-Yan Liu
- Key Laboratory of Environment Change and Resources Use in Beibu Gulf, Ministry of Education, Guangxi Teachers Education University, Nanning, China
| | - Duncan D Smith
- Department of Botany, University of Wisconsin, Madison, Wisconsin
| | | | - Ava R Howard
- Department of Biology, Western Oregon University, Monmouth, Oregon
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Imran QM, Lee SU, Mun BG, Hussain A, Asaf S, Lee IJ, Yun BW. WRKYs, the Jack-of-various-Trades, Modulate Dehydration Stress in Populus davidiana-A Transcriptomic Approach. Int J Mol Sci 2019; 20:E414. [PMID: 30669402 DOI: 10.3390/ijms20020414] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 01/14/2019] [Accepted: 01/15/2019] [Indexed: 11/17/2022] Open
Abstract
Populus davidiana, native to Korea and central Asian countries, is a major contributor to the Korean forest cover. In the current study, using high-throughput RNA-seq mediated transcriptome analysis, we identified about 87 P. davidiana WRKY transcription factors (PopdaWRKY TFs) that showed differential expression to dehydration stress in both sensitive and tolerant cultivars. Our results suggested that, on average, most of the WRKY genes were upregulated in tolerant cultivars but downregulated in sensitive cultivars. Based on protein sequence alignment, P. davidiana WRKYs were classified into three major groups, I, II, III, and further subgroups. Phylogenetic analysis showed that WRKY TFs and their orthologs in Arabidopsis and rice were clustered together in the same subgroups, suggesting similar functions across species. Significant correlation was found among qRT-PCR and RNA-seq analysis. In vivo analysis using model plant Arabidopsis showed that atwrky62 (orthologous to Potri.016G137900) knockout mutants were significantly sensitive to dehydration possibly due to an inability to close their stomata under dehydration conditions. In addition, a concomitant decrease in expression of ABA biosynthetic genes was observed. The AtHK1 that regulates stomatal movement was also downregulated in atwrky62 compared to the wild type. Taken together, our findings suggest a regulatory role of PopdaWRKYs under dehydration stress.
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Guo JS, Ogle K. Antecedent soil water content and vapor pressure deficit interactively control water potential in Larrea tridentata. New Phytol 2019; 221:218-232. [PMID: 30129140 DOI: 10.1111/nph.15374] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 07/04/2018] [Indexed: 05/21/2023]
Abstract
Plant water potential Ψ is regulated by stomatal responses to atmospheric moisture demand D and soil water availability W, but the timescales of influence and interactions between these drivers of plant Ψ are poorly understood. Here, we quantify the effects of antecedent D and W on plant Ψ in the desert shrub Larrea tridentata. Repeated measurements of plant baseline water potential ΨB and diurnal water potential ΨD were analyzed in a Bayesian framework to evaluate the influence of antecedent D and W at daily and subdaily timescales. Both ΨB and ΨD exhibited negative, 2- to 4-d lagged responses to daily-scale D; conversely, plant ΨD responded almost instantaneously to subdaily D, though the direction of this response depended on antecedent moisture conditions. Plant ΨB and ΨD responded positively and immediately (no lag) to shallow W, which contrasts the negative, lagged (6-7 d) response to deep W. The changing sensitivity of ΨD to subdaily D highlights shifting modes of plant Ψ regulation: D effects on ΨD range from negative to neutral to positive depending on past conditions and time of day. Explicit consideration of antecedent conditions across multiple timescales can reveal important complexities in plant responses.
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Affiliation(s)
- Jessica S Guo
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, 86011, USA
- The Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Kiona Ogle
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, 86011, USA
- The Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, 86011, USA
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, 86011, USA
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Sperry JS, Venturas MD, Anderegg WRL, Mencuccini M, Mackay DS, Wang Y, Love DM. Predicting stomatal responses to the environment from the optimization of photosynthetic gain and hydraulic cost. Plant Cell Environ 2017; 40:816-830. [PMID: 27764894 DOI: 10.1111/pce.12852] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 09/28/2016] [Accepted: 10/06/2016] [Indexed: 05/22/2023]
Abstract
Stomatal regulation presumably evolved to optimize CO2 for H2 O exchange in response to changing conditions. If the optimization criterion can be readily measured or calculated, then stomatal responses can be efficiently modelled without recourse to empirical models or underlying mechanism. Previous efforts have been challenged by the lack of a transparent index for the cost of losing water. Yet it is accepted that stomata control water loss to avoid excessive loss of hydraulic conductance from cavitation and soil drying. Proximity to hydraulic failure and desiccation can represent the cost of water loss. If at any given instant, the stomatal aperture adjusts to maximize the instantaneous difference between photosynthetic gain and hydraulic cost, then a model can predict the trajectory of stomatal responses to changes in environment across time. Results of this optimization model are consistent with the widely used Ball-Berry-Leuning empirical model (r2 > 0.99) across a wide range of vapour pressure deficits and ambient CO2 concentrations for wet soil. The advantage of the optimization approach is the absence of empirical coefficients, applicability to dry as well as wet soil and prediction of plant hydraulic status along with gas exchange.
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Affiliation(s)
- John S Sperry
- Department of Biology, University of Utah, 257 S 1400E, Salt Lake City, UT, 84112, USA
| | - Martin D Venturas
- Department of Biology, University of Utah, 257 S 1400E, Salt Lake City, UT, 84112, USA
| | - William R L Anderegg
- Department of Biology, University of Utah, 257 S 1400E, Salt Lake City, UT, 84112, USA
| | - Maurizio Mencuccini
- School of GeoSciences, University of Edinburgh, West Mains Road, Edinburgh, EH9 3Ju, UK
- ICREA at CREAF, Cerdanyola del Vallès, Barcelona, 08193, Spain
| | - D Scott Mackay
- Department of Geography, State University of New York, Buffalo, NY, 14260, USA
| | - Yujie Wang
- Department of Biology, University of Utah, 257 S 1400E, Salt Lake City, UT, 84112, USA
| | - David M Love
- Department of Biology, University of Utah, 257 S 1400E, Salt Lake City, UT, 84112, USA
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Tan Y, Li M, Yang Y, Sun X, Wang N, Liang B, Ma F. Overexpression of MpCYS4, A Phytocystatin Gene from Malus prunifolia (Willd.) Borkh., Enhances Stomatal Closure to Confer Drought Tolerance in Transgenic Arabidopsis and Apple. Front Plant Sci 2017; 8:33. [PMID: 28174579 PMCID: PMC5258747 DOI: 10.3389/fpls.2017.00033] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Accepted: 01/06/2017] [Indexed: 05/22/2023]
Abstract
Phytocystatins (PhyCys) comprise a group of inhibitors for cysteine proteinases in plants. They play a wide range of important roles in regulating endogenous processes and protecting plants against various environmental stresses, but the underlying mechanisms remain largely unknown. Here, we detailed the biological functions of MpCYS4, a member of cystatin genes isolated from Malus prunifolia. This gene was activated under water deficit, heat (40°C), exogenous abscisic acid (ABA), or methyl viologen (MV) (Tan et al., 2014a). At cellular level, MpCYS4 protein was found to be localized in the nucleus, cytoplasm, and plasma membrane of onion epidermal cells. Recombinant MpCYS4 cystatin expressed in Escherichia coli was purified and it exhibited cysteine protease inhibitor activity. Transgenic overexpression of MpCYS4 in Arabidopsis (Arabidopsis thaliana) and apple (Malus domestica) led to ABA hypersensitivity and series of ABA-associated phenotypes, such as enhanced ABA-induced stomatal closing, altered expression of many ABA/stress-responsive genes, and enhanced drought tolerance. Taken together, our results demonstrate that MpCYS4 is involved in ABA-mediated stress signal transduction and confers drought tolerance at least in part by enhancing stomatal closure and up-regulating the transcriptional levels of ABA- and drought-related genes. These findings provide new insights into the molecular mechanisms by which phytocystatins influence plant growth, development, and tolerance to stress.
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Song Y, Jiang C, Gao L. Polychromatic Supplemental Lighting from underneath Canopy Is More Effective to Enhance Tomato Plant Development by Improving Leaf Photosynthesis and Stomatal Regulation. Front Plant Sci 2016; 7:1832. [PMID: 28018376 PMCID: PMC5145862 DOI: 10.3389/fpls.2016.01832] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 11/21/2016] [Indexed: 05/19/2023]
Abstract
Light insufficient stress caused by canopy interception and mutual shading is a major factor limiting plant growth and development in intensive crop cultivation. Supplemental lighting can be used to give light to the lower canopy leaves and is considered to be an effective method to cope with low irradiation stress. Leaf photosynthesis, stomatal regulation, and plant growth and development of young tomato plants were examined to estimate the effects of supplemental lighting with various composite spectra and different light orientations. Light-emitting diodes (LEDs) of polychromatic light quality, red + blue (R/B), white + red + blue (W/R/B), white + red + far-red (W/R/FR), and white + blue (W/B) were assembled from the underneath canopy or from the inner canopy as supplemental lighting resources. The results showed that the use of supplemental lighting significantly increased the photosynthetic efficiency, and reduced stomatal closure while promoting plant growth. Among all supplemental lighting treatments, the W/R/B and W/B from the underneath canopy had best performance. The different photosynthetic performances among the supplemental lighting treatments are resulted from variations in CO2 utilization. The enhanced blue light fraction in the W/R/B and W/B could better stimulate stomatal opening and promote photosynthetic electron transport activity, thus better improving photosynthetic rate. Compared with the inner canopy treatment, the supplemental lighting from the underneath canopy could better enhance the carbon dioxide assimilation efficiency and excessive energy dissipation, leading to an improved photosynthetic performance. Stomatal morphology was highly correlated to leaf photosynthesis and plant development, and should thus be an important determinant for the photosynthesis and the growth of greenhouse tomatoes.
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Affiliation(s)
- Yu Song
- College of Horticulture, China Agricultural UniversityBeijing, China
- Institute of Germplasm Resources, Xinjiang Academy of Agricultural ScienceUrumqi, China
| | - Chengyao Jiang
- Graduate School of Horticulture, Chiba UniversityMatsudo, Japan
| | - Lihong Gao
- College of Horticulture, China Agricultural UniversityBeijing, China
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34
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Sperry JS, Wang Y, Wolfe BT, Mackay DS, Anderegg WRL, McDowell NG, Pockman WT. Pragmatic hydraulic theory predicts stomatal responses to climatic water deficits. New Phytol 2016; 212:577-589. [PMID: 27329266 DOI: 10.1111/nph.14059] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 05/13/2016] [Indexed: 05/04/2023]
Abstract
Ecosystem models have difficulty predicting plant drought responses, partially from uncertainty in the stomatal response to water deficits in soil and atmosphere. We evaluate a 'supply-demand' theory for water-limited stomatal behavior that avoids the typical scaffold of empirical response functions. The premise is that canopy water demand is regulated in proportion to threat to supply posed by xylem cavitation and soil drying. The theory was implemented in a trait-based soil-plant-atmosphere model. The model predicted canopy transpiration (E), canopy diffusive conductance (G), and canopy xylem pressure (Pcanopy ) from soil water potential (Psoil ) and vapor pressure deficit (D). Modeled responses to D and Psoil were consistent with empirical response functions, but controlling parameters were hydraulic traits rather than coefficients. Maximum hydraulic and diffusive conductances and vulnerability to loss in hydraulic conductance dictated stomatal sensitivity and hence the iso- to anisohydric spectrum of regulation. The model matched wide fluctuations in G and Pcanopy across nine data sets from seasonally dry tropical forest and piñon-juniper woodland with < 26% mean error. Promising initial performance suggests the theory could be useful in improving ecosystem models. Better understanding of the variation in hydraulic properties along the root-stem-leaf continuum will simplify parameterization.
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Affiliation(s)
- John S Sperry
- Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA.
| | - Yujie Wang
- Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA
| | - Brett T Wolfe
- Smithsonian Tropical Research Institute, PO Box 0843-03092, Balboa, Panama
| | - D Scott Mackay
- Department of Geography, State University of New York, Buffalo, NY, 14260, USA
| | | | - Nate G McDowell
- Earth and Environmental Sciences Division, Los Alamos National Lab, Los Alamos, NM, 87545, USA
| | - William T Pockman
- Biology Department, University of New Mexico, Albuquerque, NM, 87131, USA
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35
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Eller CB, Lima AL, Oliveira RS. Cloud forest trees with higher foliar water uptake capacity and anisohydric behavior are more vulnerable to drought and climate change. New Phytol 2016; 211:489-501. [PMID: 27038126 DOI: 10.1111/nph.13952] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 02/25/2016] [Indexed: 05/24/2023]
Abstract
Many tropical montane cloud forest (TMCF) trees are capable of foliar water uptake (FWU) during leaf-wetting events. In this study, we tested the hypothesis that maintenance of leaf turgor during periods of fog exposure and soil drought is related to species' FWU capacity. We conducted several experiments using apoplastic tracers, deuterium labeling and leaf immersion in water to evaluate differences in FWU among three common TMCF tree species. We also measured the effect of regular fog exposure on the leaf water potential of plants subjected to soil drought and used these data to model species' response to long-term drought. All species were able to absorb water through their leaf cuticles and/or trichomes, although the capacity to do so differed between species. During the drought experiment, the species with higher FWU capacity maintained leaf turgor for a longer period when exposed to fog, whereas the species with lower FWU exerted tighter stomatal regulation to maintain leaf turgor. Model results suggest that without fog, species with high FWU are more likely to lose turgor during seasonal droughts. We show that leaf-wetting events are essential for trees with high FWU, which tend to be more anisohydric, maintaining leaf turgor during seasonal droughts.
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Affiliation(s)
- Cleiton B Eller
- Department of Plant Biology, Institute of Biology, CP6109, University of Campinas - UNICAMP, Campinas, SP, 13083-970, Brazil
| | - Aline L Lima
- Center of Studies and Environmental Research - NEPAM, University of Campinas - UNICAMP, Campinas, SP, 13083-862, Brazil
| | - Rafael S Oliveira
- Department of Plant Biology, Institute of Biology, CP6109, University of Campinas - UNICAMP, Campinas, SP, 13083-970, Brazil
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36
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Bustan A, Dag A, Yermiyahu U, Erel R, Presnov E, Agam N, Kool D, Iwema J, Zipori I, Ben-Gal A. Fruit load governs transpiration of olive trees. Tree Physiol 2016; 36:380-91. [PMID: 26802540 PMCID: PMC4885946 DOI: 10.1093/treephys/tpv138] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2015] [Accepted: 12/01/2015] [Indexed: 05/24/2023]
Abstract
We tested the hypothesis that whole-tree water consumption of olives (Olea europaea L.) is fruit load-dependent and investigated the driving physiological mechanisms. Fruit load was manipulated in mature olives grown in weighing-drainage lysimeters. Fruit was thinned or entirely removed from trees at three separate stages of growth: early, mid and late in the season. Tree-scale transpiration, calculated from lysimeter water balance, was found to be a function of fruit load, canopy size and weather conditions. Fruit removal caused an immediate decline in water consumption, measured as whole-plant transpiration normalized to tree size, which persisted until the end of the season. The later the execution of fruit removal, the greater was the response. The amount of water transpired by a fruit-loaded tree was found to be roughly 30% greater than that of an equivalent low- or nonyielding tree. The tree-scale response to fruit was reflected in stem water potential but was not mirrored in leaf-scale physiological measurements of stomatal conductance or photosynthesis. Trees with low or no fruit load had higher vegetative growth rates. However, no significant difference was observed in the overall aboveground dry biomass among groups, when fruit was included. This case, where carbon sources and sinks were both not limiting, suggests that the role of fruit on water consumption involves signaling and alterations in hydraulic properties of vascular tissues and tree organs.
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Affiliation(s)
- Amnon Bustan
- Gilat Research Center, Agricultural Research Organization, mobile post Negev 85280, Israel Desert Agro-Research Center, Ramat-Negev R&D, D.N. Halutza 85515, Israel
| | - Arnon Dag
- Gilat Research Center, Agricultural Research Organization, mobile post Negev 85280, Israel
| | - Uri Yermiyahu
- Gilat Research Center, Agricultural Research Organization, mobile post Negev 85280, Israel
| | - Ran Erel
- Gilat Research Center, Agricultural Research Organization, mobile post Negev 85280, Israel
| | - Eugene Presnov
- Gilat Research Center, Agricultural Research Organization, mobile post Negev 85280, Israel
| | - Nurit Agam
- Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Be'er Sheva 84990, Israel
| | - Dilia Kool
- Gilat Research Center, Agricultural Research Organization, mobile post Negev 85280, Israel
| | - Joost Iwema
- Gilat Research Center, Agricultural Research Organization, mobile post Negev 85280, Israel Soil Physics, Ecohydrology and Groundwater Management, Wageningen University, 6700AA Wageningen, The Netherlands Present address: Department of Civil Engineering, University of Bristol, Bristol BS8 1TR, UK
| | - Isaac Zipori
- Gilat Research Center, Agricultural Research Organization, mobile post Negev 85280, Israel
| | - Alon Ben-Gal
- Gilat Research Center, Agricultural Research Organization, mobile post Negev 85280, Israel
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Merilo E, Jalakas P, Laanemets K, Mohammadi O, Hõrak H, Kollist H, Brosché M. Abscisic Acid Transport and Homeostasis in the Context of Stomatal Regulation. Mol Plant 2015; 8:1321-33. [PMID: 26099923 DOI: 10.1016/j.molp.2015.06.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 05/04/2015] [Accepted: 06/08/2015] [Indexed: 05/18/2023]
Abstract
The discovery of cytosolic ABA receptors is an important breakthrough in stomatal research; signaling via these receptors is involved in determining the basal stomatal conductance and stomatal responsiveness. However, the source of ABA in guard cells is still not fully understood. The level of ABA increases in guard cells by de novo synthesis, recycling from inactive conjugates via β-glucosidases BG1 and BG2 and by import, whereas it decreases by hydroxylation, conjugation, and export. ABA importers include the NRT1/PTR family protein AIT1, ATP-binding cassette protein ABCG40, and possibly ABCG22, whereas the DTX family member DTX50 and ABCG25 function as ABA exporters. Here, we review the proteins involved in ABA transport and homeostasis and their physiological role in stomatal regulation. Recent experiments suggest that functional redundancy probably exists among ABA transporters between vasculature and guard cells and ABA recycling proteins, as stomatal functioning remained intact in abcg22, abcg25, abcg40, ait1, and bg1bg2 mutants. Only the initial response to reduced air humidity was significantly delayed in abcg22. Considering the reports showing autonomous ABA synthesis in guard cells, we discuss that rapid stomatal responses to atmospheric factors might depend primarily on guard cell-synthesized ABA, whereas in the case of long-term soil water deficit, ABA synthesized in the vasculature might have a significant role.
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Affiliation(s)
- Ebe Merilo
- Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia
| | - Pirko Jalakas
- Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia
| | - Kristiina Laanemets
- Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia
| | - Omid Mohammadi
- Division of Plant Biology, Department of Biosciences, University of Helsinki, P.O. Box 65 (Viikinkaari 1), FI-00014 Helsinki, Finland
| | - Hanna Hõrak
- Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia
| | - Hannes Kollist
- Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia.
| | - Mikael Brosché
- Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia; Division of Plant Biology, Department of Biosciences, University of Helsinki, P.O. Box 65 (Viikinkaari 1), FI-00014 Helsinki, Finland
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Duan H, O'Grady AP, Duursma RA, Choat B, Huang G, Smith RA, Jiang Y, Tissue DT. Drought responses of two gymnosperm species with contrasting stomatal regulation strategies under elevated [CO2] and temperature. Tree Physiol 2015; 35:756-70. [PMID: 26063706 DOI: 10.1093/treephys/tpv047] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 04/28/2015] [Indexed: 05/06/2023]
Abstract
Future climate regimes characterized by rising [CO2], rising temperatures and associated droughts may differentially affect tree growth and physiology. However, the interactive effects of these three factors are complex because elevated [CO2] and elevated temperature may generate differential physiological responses during drought. To date, the interactive effects of elevated [CO2] and elevated temperature on drought-induced tree mortality remain poorly understood in gymnosperm species that differ in stomatal regulation strategies. Water relations and carbon dynamics were examined in two species with contrasting stomatal regulation strategies: Pinus radiata D. Don (relatively isohydric gymnosperm; regulating stomata to maintain leaf water potential above critical thresholds) and Callitris rhomboidea R. Br (relatively anisohydric gymnosperm; allowing leaf water potential to decline as the soil dries), to assess response to drought as a function of [CO2] and temperature. Both species were grown in two [CO2] (C(a) (ambient, 400 μl l(-1)) and C(e) (elevated, 640 μl l(-1))) and two temperature (T(a) (ambient) and T(e) (ambient +4 °C)) treatments in a sun-lit glasshouse under well-watered conditions. Drought plants were then exposed to a progressive drought until mortality. Prior to mortality, extensive xylem cavitation occurred in both species, but significant depletion of non-structural carbohydrates was not observed in either species. Te resulted in faster mortality in P. radiata, but it did not modify the time-to-mortality in C. rhomboidea. C(e) did not delay the time-to-mortality in either species under drought or T(e) treatments. In summary, elevated temperature (+4 °C) had greater influence than elevated [CO2] (+240 μl l(-1)) on drought responses of the two studied gymnosperm species, while stomatal regulation strategies did not generally affect the relative contributions of hydraulic failure and carbohydrate depletion to mortality under severe drought.
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Affiliation(s)
- Honglang Duan
- Institute of Ecology and Environmental Science, Nanchang Institute of Technology, Nanchang, Jiangxi 330099, China
| | - Anthony P O'Grady
- CSIRO Land and Water Flagship, Private Bag 12, Hobart, Tasmania 7001, Australia
| | - Remko A Duursma
- Hawkesbury Institute for the Environment, University of Western Sydney, Hawkesbury Campus, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - Brendan Choat
- Hawkesbury Institute for the Environment, University of Western Sydney, Hawkesbury Campus, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - Guomin Huang
- Hawkesbury Institute for the Environment, University of Western Sydney, Hawkesbury Campus, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - Renee A Smith
- Hawkesbury Institute for the Environment, University of Western Sydney, Hawkesbury Campus, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - Yanan Jiang
- Institute of Ecology and Environmental Science, Nanchang Institute of Technology, Nanchang, Jiangxi 330099, China
| | - David T Tissue
- Hawkesbury Institute for the Environment, University of Western Sydney, Hawkesbury Campus, Locked Bag 1797, Penrith, NSW 2751, Australia
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Erel R, Ben-Gal A, Dag A, Schwartz A, Yermiyahu U. Sodium replacement of potassium in physiological processes of olive trees (var. Barnea) as affected by drought. Tree Physiol 2014; 34:1102-17. [PMID: 25281842 DOI: 10.1093/treephys/tpu081] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Potassium (K) is a macro-nutrient understood to play a role in the physiological performance of plants under drought. In some plant species, sodium (Na) can partially substitute K. Although a beneficial role of Na is well established, information regarding its nutritional role in trees is scant and its function under conditions of drought is not fully understood. The objective of the present study was to evaluate the role of K and its possible replacement by Na in olive's (Olea europaea L.) response to drought. Young and bearing olive trees were grown in soilless culture and exposed to gradual drought. In the presence of Na, trees were tolerant of extremely low K concentrations. Depletion of K and Na resulted in ∼50% reduction in CO2 assimilation rate when compared with sufficiently fertilized control plants. Sodium was able to replace K and recover the assimilation rate to nearly optimum level. The inhibitory effect of K deficiency on photosynthesis was more pronounced under high stomatal conductance. Potassium was not found to facilitate drought tolerance mechanisms in olives. Moreover, stomatal control machinery was not significantly impaired by K deficiency, regardless of water availability. Under drought, leaf water potential was affected by K and Na. High environmental K and Na increased leaf starch content and affected the soluble carbohydrate profile in a similar manner. These results identify olive as a species capable of partly replacing K by Na. The nutritional effect of K and Na was shown to be independent of plant water status. The beneficial effect of Na on photosynthesis and carbohydrates under insufficient K indicates a positive role of Na in metabolism and photosynthetic reactions.
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Affiliation(s)
- Ran Erel
- Institute of Soil, Water and Environmental Sciences, Gilat Research Center, Agricultural Research Organization, Mobile Post Negev 85-280, Israel The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Alon Ben-Gal
- Institute of Soil, Water and Environmental Sciences, Gilat Research Center, Agricultural Research Organization, Mobile Post Negev 85-280, Israel
| | - Arnon Dag
- Institute of Plant Sciences, Gilat Research Center, Agricultural Research Organization, Mobile Post Negev 85-280, Israel
| | - Amnon Schwartz
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Uri Yermiyahu
- Institute of Soil, Water and Environmental Sciences, Gilat Research Center, Agricultural Research Organization, Mobile Post Negev 85-280, Israel
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Mitchell PJ, O'Grady AP, Tissue DT, Worledge D, Pinkard EA. Co-ordination of growth, gas exchange and hydraulics define the carbon safety margin in tree species with contrasting drought strategies. Tree Physiol 2014; 34:443-58. [PMID: 24664613 DOI: 10.1093/treephys/tpu014] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Gas exchange, growth, water transport and carbon (C) metabolism diminish during drought according to their respective sensitivities to declining water status. The timing of this sequence of declining physiological functions may determine how water and C relations compromise plant survival. In this paper, we test the hypothesis that the degree of asynchrony between declining C supply (photosynthesis) and C demand (growth and respiration) determines the rate and magnitude of changes in whole-plant non-structural carbohydrates (NSC) during drought. Two complementary experiments using two tree species (Eucalyptus globulus Labill. and Pinus radiata D. Don) with contrasting drought response strategies were performed to (i) assess changes in radial stem growth, transpiration, leaf water potential and gas exchange in response to chronic drought, and (ii) evaluate the concomitant impacts of these drought responses on the temporal patterns of NSC during terminal drought. The three distinct phases of water stress were delineated by thresholds of growth cessation and stomatal closure that defined the 'carbon safety margin' (i.e., the difference between leaf water potential when growth is zero and leaf water potential when net photosynthesis is zero). A wider C safety margin in E. globulus was defined by an earlier cessation of growth relative to photosynthesis that reduced the demand for NSC while maintaining C acquisition. By contrast, the narrower C safety margin in P. radiata was characterized by a synchronous decline in growth and photosynthesis, whereby growth continued under a declining supply of NSC from photosynthesis. The narrower C safety margin in P. radiata was associated with declines in starch concentrations after ∼ 90 days of chronic drought and significant depletion of starch in all organs at mortality. The observed divergence in the sensitivity of drought responses is indicative of a potential trade-off between maintaining hydraulic safety and adequate C availability.
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Affiliation(s)
- P J Mitchell
- CSIRO Ecosystem Sciences, Climate Adaptation Flagship, Private Bag 12, Hobart, TAS 7001, Australia
| | - A P O'Grady
- CSIRO Ecosystem Sciences, Climate Adaptation Flagship, Private Bag 12, Hobart, TAS 7001, Australia
| | - D T Tissue
- Hawkesbury Institute for the Environment, University of Western Sydney, Bourke Street, Richmond, NSW 2753, Australia
| | - D Worledge
- CSIRO Ecosystem Sciences, Climate Adaptation Flagship, Private Bag 12, Hobart, TAS 7001, Australia
| | - E A Pinkard
- CSIRO Ecosystem Sciences, Climate Adaptation Flagship, Private Bag 12, Hobart, TAS 7001, Australia
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Abstract
The drought tolerance of three economically important apple cultivars, Golden Delicious, Braeburn and Red Delicious, was analysed. The work offers insights into the hydraulics of these high-yield trees and indicates a possible hydraulic limitation of carbon gain. The hydraulic safety and efficiency of branch xylem and leaves were quantified, drought tolerance of living tissues was measured and stomatal regulation, turgor-loss point and osmotic potential at full turgor were analysed. Physiological measurements were correlated with anatomical parameters, such as conduit diameter, cell-wall reinforcement, stomatal density and stomatal pore length. Hydraulic safety differed considerably between the three cultivars with Golden Delicious being significantly less vulnerable to drought-induced embolism than Braeburn and Red Delicious. In Golden Delicious, leaves were less resistant than branch xylem, while in the other cultivars leaves were more resistant than branch xylem. Hydraulic efficiency and xylem anatomical measurements indicate differences in pit properties, which may also be responsible for variations in hydraulic safety. In all three cultivars, full stomatal closure occurred at water potentials where turgor had already been lost and severe loss of hydraulic conductivity as well as damage to living cells had been induced. The consequential negative safety margins pose a risk for hydraulic failure but facilitate carbon gain, which is further improved by the observed high stomatal conductance. Maximal stomatal conductance was clearly seen to be related to stomatal density and size. Based on our results, these three high-yield Malus domestica Borkh. cultivars span a wide range of drought tolerances, appear optimized for maximal carbon gain and, thus, all perform best under well-managed growing conditions.
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Affiliation(s)
- Barbara Beikircher
- Institute of Botany, University of Innsbruck, Sternwartestraße 15, 6020 Innsbruck, Austria
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Soares-Cordeiro AS, Driscoll SP, Arrabaça MC, Foyer CH. Dorsoventral variations in dark chilling effects on photosynthesis and stomatal function in Paspalum dilatatum leaves. J Exp Bot 2011; 62:687-99. [PMID: 21030386 PMCID: PMC3003811 DOI: 10.1093/jxb/erq302] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2010] [Revised: 08/12/2010] [Accepted: 09/06/2010] [Indexed: 05/24/2023]
Abstract
The effects of dark chilling on the leaf-side-specific regulation of photosynthesis were characterized in the C(4) grass Paspalum dilatatum. CO(2)- and light-response curves for photosynthesis and associated parameters were measured on whole leaves and on each leaf side independently under adaxial and abaxial illumination before and after plants were exposed to dark chilling for one or two consecutive nights. The stomata closed on the adaxial sides of the leaves under abaxial illumination and no CO(2) uptake could be detected on this surface. However, high rates of whole leaf photosynthesis were still observed because CO(2) assimilation rates were increased on the abaxial sides of the leaves under abaxial illumination. Under adaxial illumination both leaf surfaces contributed to the inhibition of whole leaf photosynthesis observed after one night of chilling. After two nights of chilling photosynthesis remained inhibited on the abaxial side of the leaf but the adaxial side had recovered, an effect related to increased maximal ribulose-1,5-bisphosphate carboxylation rates (V(cmax)) and enhanced maximal electron transport rates (J(max)). Under abaxial illumination, whole leaf photosynthesis was decreased only after the second night of chilling. The chilling-dependent inhibition of photosynthesis was located largely on the abaxial side of the leaf and was related to decreased V(cmax) and J(max), but not to the maximal phosphoenolpyruvate carboxylase carboxylation rate (V(pmax)). Each side of the leaf therefore exhibits a unique sensitivity to stress and recovery. Side-specific responses to stress are related to differences in the control of enzyme and photosynthetic electron transport activities.
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Affiliation(s)
- Ana Sofia Soares-Cordeiro
- Centro de Engenharia Biológica e Departamento de Biologia Vegetal, Faculdade de Ciências da Universidade de Lisboa, Campo Grande 1749-016 Lisboa, Portugal
| | - Simon P. Driscoll
- Centre of Plant Science, Research Institute of Integrative and Comparative Biology, Faculty of Biological Science, University of Leeds, Leeds LS2 9JT, UK
| | - Maria Celeste Arrabaça
- Centro de Engenharia Biológica e Departamento de Biologia Vegetal, Faculdade de Ciências da Universidade de Lisboa, Campo Grande 1749-016 Lisboa, Portugal
| | - Christine H. Foyer
- Centre of Plant Science, Research Institute of Integrative and Comparative Biology, Faculty of Biological Science, University of Leeds, Leeds LS2 9JT, UK
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Rogiers SY, Greer DH, Hutton RJ, Landsberg JJ. Does night-time transpiration contribute to anisohydric behaviour in a Vitis vinifera cultivar? J Exp Bot 2009; 60:3751-63. [PMID: 19584116 PMCID: PMC2736890 DOI: 10.1093/jxb/erp217] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2009] [Revised: 06/05/2009] [Accepted: 06/15/2009] [Indexed: 05/19/2023]
Abstract
The hypothesis that vines of the Semillon wine grape variety show anisohydric behaviour was tested, i.e. that tissue hydration is unstable under fluctuating environmental conditions. Stomatal conductance and transpiration rates from leaves were measured during the day and at night. Leaf water potential (Psi(l)) in Semillon was negatively correlated to vapour pressure deficit (VPD) both predawn and during the day. Furthermore, Psi(l) fell to significantly lower values than in any of the nine other varieties examined. Night-time values of stomatal conductance (g(n)) and transpiration (E(n)) in Semillon were up to four times higher than in other varieties; plants enclosed in plastic bags overnight to reduce E(n) resulted in better plant-soil equilibration so that predawn Psi(l) in Semillon was the same as in Grenache. These data indicate that the hypothesis is supported, and that night-time transpiration contributes significantly to the low Psi(l) values in Semillon during warm, dry nights. The other contributing factor is daytime stomatal conductance (g(day)), which in Semillon leaves was higher than in other varieties, although the decline in g(day) with increasing VPD was greater in Semillon than in Shiraz or Grenache. The high values of g(day) were associated with high rates of transpiration (E(day)) by Semillon through a day when VPD reached 4.5 kPa. When compared to other varieties, Semillon was not unusual in terms of root length density, stomatal density, xylem sap abscisic acid, or leaf electrolyte leakage. Night-time and daytime water loss and insufficient stomatal regulation therefore account for the tendency to anisohydric behaviour shown by Semillon.
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Affiliation(s)
- Suzy Y Rogiers
- National Wine and Grape Industry Centre, NSW Department of Primary Industries and Charles Sturt University, Wagga Wagga, NSW 2678, Australia.
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Abstract
Distinct potassium, anion, and calcium channels in the plasma membrane and vacuolar membrane of plant cells have been identified and characterized by patch clamping. Primarily owing to advances in Arabidopsis genetics and genomics, and yeast functional complementation, many of the corresponding genes have been identified. Recent advances in our understanding of ion channel genes that mediate signal transduction and ion transport are discussed here. Some plant ion channels, for example, ALMT and SLAC anion channel subunits, are unique. The majority of plant ion channel families exhibit homology to animal genes; such families include both hyperpolarization- and depolarization-activated Shaker-type potassium channels, CLC chloride transporters/channels, cyclic nucleotide-gated channels, and ionotropic glutamate receptor homologs. These plant ion channels offer unique opportunities to analyze the structural mechanisms and functions of ion channels. Here we review gene families of selected plant ion channel classes and discuss unique structure-function aspects and their physiological roles in plant cell signaling and transport.
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Affiliation(s)
- John M. Ward
- Department of Plant Biology, University of Minnesota, St. Paul, Minnesota 55108;
| | - Pascal Mäser
- Institute of Cell Biology, University of Bern, CH-3012 Bern, Switzerland
| | - Julian I. Schroeder
- Division of Biological Sciences, Cell and Developmental Biology Section, University of California, San Diego, La Jolla, California 92093;
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Affiliation(s)
- John S Sperry
- Biology Department, 257S 1400E, University of Utah, Salt Lake City, UT 84112, USA (tel +1801 5850379; fax +1801 5814668; email )
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