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Miao Y, Gao X, Li B, Wang W, Bai L. Low red to far-red light ratio promotes salt tolerance by improving leaf photosynthetic capacity in cucumber. FRONTIERS IN PLANT SCIENCE 2023; 13:1053780. [PMID: 36684769 PMCID: PMC9853560 DOI: 10.3389/fpls.2022.1053780] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 11/30/2022] [Indexed: 06/17/2023]
Abstract
Soil salinity severely inhibits leaf photosynthesis and limits agricultural production. Red to far-red light ratio (R/FR) affects leaf photosynthesis under salt stress, however, its regulation mechanism is still largely unknown. This study investigated the effects of different R/FR on plant growth, gas exchange parameters, photosynthetic electron transport, Calvin cycle and key gene expression under salt stress. Cucumber seedlings were exposed to four treatments including 0 mM NaCl and R/FR=7 (L7, control), 0 mM NaCl and R/FR=0.7 (L0.7), 80 mM NaCl and R/FR=7 (H7) and 80 mM NaCl and R/FR=0.7 (H0.7) for 9 days in an artificial climate chamber. The results showed that compared to L7 treatment, H7 treatment significantly reduced relative growth rate (RGR), CO2 assimilation rate (P n), maximum photochemical efficiency PSII (F v/F m), most JIP-test parameters and total Rubisco activity, indicating that salt stress severely inhibited photosynthetic electron transport from PSII to PSI and blocked Calvin cycle in cucumber leaves. However, these suppressions were effectively alleviated by low R/FR addition (H0.7 treatment). Compared to H7 treatment, H0.7 treatment significantly increased RGR and P n by 209.09% and 7.59%, respectively, enhanced F v/F m, maximum quantum yield for primary photochemistry (φ Po), quantum yield for electron transport (φ Eo) and total Rubisco activity by 192.31%, 17.6%, 36.84% and 37.08%, respectively, and largely up-regulated expressions of most key genes involved in electron transport and Calvin cycle. In conclusion, low R/FR effectively alleviated the negative effects of salt stress on leaf photosynthesis by accelerating photosynthetic electron transport from PSII to PQ pool and promoting Calvin cycle in cucumber plants. It provides a novel environmentally friendly light-quality regulation technology for high efficiency salt-resistant vegetable production.
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Affiliation(s)
- Yanxiu Miao
- College of Horticulture, Shanxi Agricultural University, Jinzhong, China
- Collaborative Innovation Center for Improving Quality and Increase profits of Protected Vegetables in Shanxi, Shanxi Agricultural University, Jinzhong, China
| | - Xingxing Gao
- College of Horticulture, Shanxi Agricultural University, Jinzhong, China
| | - Bin Li
- College of Horticulture, Shanxi Agricultural University, Jinzhong, China
- Collaborative Innovation Center for Improving Quality and Increase profits of Protected Vegetables in Shanxi, Shanxi Agricultural University, Jinzhong, China
| | - Wenjiao Wang
- College of Horticulture, Shanxi Agricultural University, Jinzhong, China
- Collaborative Innovation Center for Improving Quality and Increase profits of Protected Vegetables in Shanxi, Shanxi Agricultural University, Jinzhong, China
| | - Longqiang Bai
- College of Horticulture, Shanxi Agricultural University, Jinzhong, China
- Collaborative Innovation Center for Improving Quality and Increase profits of Protected Vegetables in Shanxi, Shanxi Agricultural University, Jinzhong, China
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Environmental and Cultivation Factors Affect the Morphology, Architecture and Performance of Root Systems in Soilless Grown Plants. HORTICULTURAE 2021. [DOI: 10.3390/horticulturae7080243] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Soilless culture systems are currently one of the fastest-growing sectors in horticulture. The plant roots are confined into a specific rootzone and are exposed to environmental changes and cultivation factors. The recent scientific evidence regarding the effects of several environmental and cultivation factors on the morphology, architecture, and performance of the root system of plants grown in SCS are the objectives of this study. The effect of root restriction, nutrient solution, irrigation frequency, rootzone temperature, oxygenation, vapour pressure deficit, lighting, rootzone pH, root exudates, CO2, and beneficiary microorganisms on the functionality and performance of the root system are discussed. Overall, the main results of this review demonstrate that researchers have carried out great efforts in innovation to optimize SCS water and nutrients supply, proper temperature, and oxygen levels at the rootzone and effective plant–beneficiary microorganisms, while contributing to plant yields. Finally, this review analyses the new trends based on emerging technologies and various tools that might be exploited in a smart agriculture approach to improve root management in soilless cropping while procuring a deeper understanding of plant root–shoot communication.
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Studies of Vegetative Growth, Inflorescence Development and Eco-Dormancy Formation of Abscission Layers in Streptocarpus formosus (Gesneriaceae). HORTICULTURAE 2021. [DOI: 10.3390/horticulturae7060120] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Streptocarpus formosus (Hilliard & B.L. Burtt) T.J. Edwards is a flowering herbaceous perennial indigenous to South Africa and is part of the rosulate group of herbaceous acaulescent plants within the Gesneriaceae family. According to the National Assessment database for the Red List of South African Plants version 2020.1., the plant is listed as rare. The ornamental use of S. formosus has untapped commercial potential as a flowering indoor pot plant, an outdoor bedding plant for shade and as a cut flower for the vase, all of which are limited by a five-month eco-dormancy period during the late autumn and all through the cold season in the short-day winter months. Viable commercial production will require cultivation techniques that produce flowering plants all year round. This study investigated the effectiveness of applying root zone heating to S. formosus plants grown in deep water culture hydroponics during the eco-dormancy period in preventing abscission layer formation and in encouraging flowering and assessed the growth activity response of the plants. The experiment was conducted over eight weeks during the winter season in the greenhouse at Kirstenbosch Botanical garden in water reservoirs, each maintained at five different experimental temperature treatments (18, 22, 26—control, 30 and 34 °C) applied to 10 sample replicates. The results showed that the lowest hydroponic root zone temperature of 18 °C had the greatest effect on the vegetative growth of S. formosus, with the highest average increases in fresh weight (1078 g), root length (211 cm), overall leaf length (362 cm) and the number of newly leaves formed (177 = n), all noted as statistically significant when compared with the other water temperature treatments, which yielded negative results from reduced vegetative growth. Findings from the study also revealed that while all heated solutions significantly prevented the formation of abscission layers of S. formosus, they had a less significant effect on inflorescence formation, with only 18 °C having the greatest positive effect on flower development.
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Anwar A, Li Y, He C, Yu X. 24-Epibrassinolide promotes NO 3- and NH 4+ ion flux rate and NRT1 gene expression in cucumber under suboptimal root zone temperature. BMC PLANT BIOLOGY 2019; 19:225. [PMID: 31146677 PMCID: PMC6543628 DOI: 10.1186/s12870-019-1838-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Accepted: 05/17/2019] [Indexed: 05/19/2023]
Abstract
BACKGROUND Suboptimal root zone temperature (RZT) causes a remarkable reduction in growth of horticultural crops during winter cultivation under greenhouse production. However, limited information is available on the effects of suboptimal RZT on nitrogen (N) metabolism in cucumber seedlings. The aim of this study is to investigate the effects of 24-Epibrassinolide (EBR) on nitrate and ammonium flux rate, N metabolism, and transcript levels of NRT1 family genes under suboptimal RZT in cucumber seedlings. RESULTS Suboptimal RZT (LT) negatively affected on cucumber growth and proportionately decreased EBR contents, bleeding rate, root activity, enzyme activities of nitrate reductase (NR), nitrite reductase (NiR), glutamine synthetase (GS), and glutamate synthase (GOGAT), nitrate (NO3-) influx rate, ammonium (NH4+) efflux rate, and transcript levels of nitrate transporter (NRT1) encoding genes. However, exogenous EBR reduced the harmful effects of suboptimal RZT and increased endogenous EBR contents, bleeding rate, root activity, enzyme activities of NR, NiR, GS, and GOGAT, NH4+ and NO3- flux rates and contents, and N accumulation. EBR-treated seedlings also upregulated the transcript levels of nitrate transporters CsNRT1.1, CsNRT1.2A, CsNRT1.2B, CsNRT1.2C, CsNRT1.3, CsNRT1.4A, CsNRT1.5B, CsNRT1.5C, CsNRT1.9, and CsNRT1.10, and downregulated CsNRT1.5A and CsNRT1.8. LT treatment upregulated the expression level of CsNRT1.5A, while exogenous BZR application downregulated the expression level of NRT1 genes. CONCLUSION These results indicate that exogenous application of EBR alleviated the harmful effects of suboptimal RZT through changes in N metabolism, NH4+ and NO3- flux rates, and NRT1 gene expression, leading to improved cucumber seedlings growth. Our study provides the first evidence of the role of EBR in the response to suboptimal RZT in cucumber, and can be used to improve vegetable production.
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Affiliation(s)
- Ali Anwar
- The Institute of Vegetables and Flowers, Chinese Academy of Agricultural Scieces, Beijing, China
| | - Yansu Li
- The Institute of Vegetables and Flowers, Chinese Academy of Agricultural Scieces, Beijing, China
| | - Chaoxing He
- The Institute of Vegetables and Flowers, Chinese Academy of Agricultural Scieces, Beijing, China
| | - Xianchang Yu
- The Institute of Vegetables and Flowers, Chinese Academy of Agricultural Scieces, Beijing, China
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Cao YY, Qi CD, Li S, Wang Z, Wang X, Wang J, Ren S, Li X, Zhang N, Guo YD. Melatonin Alleviates Copper Toxicity via Improving Copper Sequestration and ROS Scavenging in Cucumber. PLANT & CELL PHYSIOLOGY 2019; 60:562-574. [PMID: 30496548 DOI: 10.1093/pcp/pcy226] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 11/20/2018] [Indexed: 05/17/2023]
Abstract
Melatonin plays an important role in stress tolerance in plants. In this study, exogenous melatonin significantly alleviated the dwarf phenotype and inhibited the decrease of plant fresh weight induced by excess copper (Cu2+). Our results indicated that melatonin alleviated Cu2+ toxicity by improving Cu2+ sequestration, carbon metabolism and ROS (reactive oxygen species) scavenging, rather than by influencing the Cu2+ uptake under excess Cu2+ conditions. Transcriptome analysis showed that melatonin broadly altered gene expression under Cu2+ stress. Melatonin increased the levels of glutathione and phytochelatin to chelate excess Cu2+ and promoted cell wall trapping, thus keeping more Cu2+ in the cell wall and vacuole. Melatonin inhibited ROS production and enhanced antioxidant systems at the transcriptional level and enzyme activities, thus building a line of defense in response to excess Cu2+. The distribution of nutrient elements was recovered by melatonin which was disturbed by Cu2+. In addition, melatonin activated carbon metabolism, especially glycolysis and the pentose phosphate pathway, to generate more ATP, an intermediate for biosynthesis. Taken together, melatonin alleviated Cu2+ toxicity in cucumber via multiple mechanisms. These results will help to resolve the toxic effects of Cu2+ stress on plant growth and development. These results can be used for new strategies to solve problems associated with Cu2+ stress.
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Affiliation(s)
- Yun-Yun Cao
- College of Horticulture, Beijing Key Laboratory of Growth and Developmental Regulation, China Agricultural University, Beijing, China
| | - Chuan-Dong Qi
- College of Horticulture, Beijing Key Laboratory of Growth and Developmental Regulation, China Agricultural University, Beijing, China
| | - Shuangtao Li
- College of Horticulture, Beijing Key Laboratory of Growth and Developmental Regulation, China Agricultural University, Beijing, China
| | - Zhirong Wang
- College of Horticulture, Beijing Key Laboratory of Growth and Developmental Regulation, China Agricultural University, Beijing, China
| | - Xiaoyun Wang
- College of Horticulture, Beijing Key Laboratory of Growth and Developmental Regulation, China Agricultural University, Beijing, China
| | - Jinfang Wang
- College of Horticulture, Beijing Key Laboratory of Growth and Developmental Regulation, China Agricultural University, Beijing, China
| | - Shuxin Ren
- School of Agriculture, Virginia State University, Petersburg, VA, USA
| | - Xingsheng Li
- Shandong Provincial Key Laboratory of Cucurbitaceae Vegetable Biological Breeding, Shandong Huasheng Agriculture Co. Ltd, Shandong, China
| | - Na Zhang
- College of Horticulture, Beijing Key Laboratory of Growth and Developmental Regulation, China Agricultural University, Beijing, China
| | - Yang-Dong Guo
- College of Horticulture, Beijing Key Laboratory of Growth and Developmental Regulation, China Agricultural University, Beijing, China
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Li Y, Li J, Gao L, Tian Y. Irrigation has more influence than fertilization on leaching water quality and the potential environmental risk in excessively fertilized vegetable soils. PLoS One 2018; 13:e0204570. [PMID: 30261079 PMCID: PMC6160137 DOI: 10.1371/journal.pone.0204570] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 09/11/2018] [Indexed: 11/18/2022] Open
Abstract
Excessive fertilization is a common agricultural practice that often negatively influence soil and environmental quality in intensive vegetable production systems in China. To reduce negative effects of excessive fertilization, current studies generally focused on fertilizer management but not irrigation. In this study, we investigated the effects of fertilization and irrigation on soil properties, leaching water characteristics, plant growth, cucumber yield, irrigation water use efficiency (IWUE) and partial factor productivity of nitrogen (PFPN) in a double cropping system. The treatments included (i) conventional irrigation with conventional N fertilization (IcNc), (ii) optimal irrigation with conventional N fertilization (IoNc), (iii) conventional irrigation with optimal N fertilization (IcNo), and (iv) optimal irrigation with optimal N fertilization (IoNo). In general, fertilization merely influenced concentrations of nitrate (NO3-), phosphorus (P) and potassium (K), but did not affect most leaching water characteristics. In contrast, irrigation influenced pH, EC and concentrations of P, K, Ca, Mg, Na and Cu. Cumulative leached amounts of NO3-, P, K, Ca, Mg, Na, Fe, Cu and Zn were significantly decreased by optimal irrigation as compared to conventional irrigation under same fertilization conditions, but not by optimal fertilization as compared to conventional fertilization under same irrigation conditions. The leachate volume was strongly positively correlated with cumulative leached amounts of all tested elements, and these relationships were obviously influenced by irrigation but not fertilization. The IoNo treatment significantly increased both IWUE and PFPN as compared to the IcNc treatment. However, the IcNo treatment only enhanced PFPN, while the IoNc treatment improved IWUE, when compared to the IcNc treatment. Our results suggested that irrigation has more influence than fertilization on leaching water quality and that the optimal irrigation combined with optimal fertilization was efficient in reducing the potential environmental risk caused by excessive fertilization in intensive vegetable production systems.
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Affiliation(s)
- Yang Li
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, China Agricultural University, Beijing, China
- College of Horticulture, Henan Agricultural University, Zhengzhou, China
| | - Juanqi Li
- College of Horticulture, Henan Agricultural University, Zhengzhou, China
| | - Lihong Gao
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, China Agricultural University, Beijing, China
- * E-mail: (YT); (LG)
| | - Yongqiang Tian
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, China Agricultural University, Beijing, China
- * E-mail: (YT); (LG)
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Li Y, Li J, Yan Y, Liu W, Zhang W, Gao L, Tian Y. Knock-Down of CsNRT2.1, a Cucumber Nitrate Transporter, Reduces Nitrate Uptake, Root length, and Lateral Root Number at Low External Nitrate Concentration. FRONTIERS IN PLANT SCIENCE 2018; 9:722. [PMID: 29911677 PMCID: PMC5992502 DOI: 10.3389/fpls.2018.00722] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Accepted: 05/14/2018] [Indexed: 05/08/2023]
Abstract
Nitrogen (N) is a macronutrient that plays a crucial role in plant growth and development. Nitrate ( NO 3 - ) is the most abundant N source in aerobic soils. Plants have evolved two adaptive mechanisms such as up-regulation of the high-affinity transport system (HATS) and alteration of the root system architecture (RSA), allowing them to cope with the temporal and spatial variation of NO 3 - . However, little information is available regarding the nitrate transporter in cucumber, one of the most important fruit vegetables in the world. In this study we isolated a nitrate transporter named CsNRT2.1 from cucumber. Analysis of the expression profile of the CsNRT2.1 showed that CsNRT2.1 is a high affinity nitrate transporter which mainly located in mature roots. Subcellular localization analysis revealed that CsNRT2.1 is a plasma membrane transporter. In N-starved CsNRT2.1 knock-down plants, both of the constitutive HATS (cHATS) and inducible HATS (iHATS) were impaired under low external NO 3 - concentration. Furthermore, the CsNRT2.1 knock-down plants showed reduced root length and lateral root numbers. Together, our results demonstrated that CsNRT2.1 played a dual role in regulating the HATS and RSA to acquire NO 3 - effectively under N limitation.
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Affiliation(s)
- Yang Li
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing, China
| | - Juanqi Li
- College of Horticulture, Henan Agricultural University, Zhengzhou, China
| | - Yan Yan
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing, China
| | - Wenqian Liu
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing, China
| | - Wenna Zhang
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing, China
| | - Lihong Gao
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing, China
| | - Yongqiang Tian
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing, China
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Li J, Li Y, Tian Y, Qu M, Zhang W, Gao L. Melatonin Has the Potential to Alleviate Cinnamic Acid Stress in Cucumber Seedlings. FRONTIERS IN PLANT SCIENCE 2017; 8:1193. [PMID: 28751899 PMCID: PMC5508022 DOI: 10.3389/fpls.2017.01193] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Accepted: 06/23/2017] [Indexed: 05/14/2023]
Abstract
Cinnamic acid (CA), which is a well-known major autotoxin secreted by the roots in cucumber continuous cropping, has been proven to exhibit inhibitory regulation of plant morphogenesis and development. Melatonin (MT) has been recently demonstrated to play important roles in alleviating plant abiotic stresses. To investigate whether MT supplementation could improve cucumber seedling growth under CA stress, we treated cucumber seeds and seedlings with/without MT under CA- or non-stress conditions, and then tested their effects on cucumber seedling growth, morphology, nutrient element content, and plant hormone. Overall, 10 μM MT best rescued cucumber seedling growth under 0.4 mM CA stress. MT was found to alleviate CA-stressed seedling growth by increasing the growth rates of cotyledons and leaves and by stimulating lateral root growth. Additionally, MT increased the allocation of newly gained dry weight in roots and improved the tolerance of cucumber seedlings to CA stress by altering the nutrient elements and hormone contents of the whole plant. These results strongly suggest that the application of MT can effectively improve cucumber seedling tolerance to CA stress through the perception and integration of morphology, nutrient element content and plant hormone signaling crosstalk.
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Affiliation(s)
- Juanqi Li
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, China Agricultural UniversityBeijing, China
| | - Yang Li
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, China Agricultural UniversityBeijing, China
| | - Yongqiang Tian
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, China Agricultural UniversityBeijing, China
| | - Mei Qu
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, China Agricultural UniversityBeijing, China
| | - Wenna Zhang
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, China Agricultural UniversityBeijing, China
| | - Lihong Gao
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, China Agricultural UniversityBeijing, China
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