Drought is one of the most severe environmental stresses affecting soybean growth and development,especially in arid and semi-arid areas.The aim of this experiment is to evaluate the effect of regulated deficit irriga...Drought is one of the most severe environmental stresses affecting soybean growth and development,especially in arid and semi-arid areas.The aim of this experiment is to evaluate the effect of regulated deficit irrigation during the vegetative stages on soybean plants and determine the amount irrigation water can be reduced without affecting the physiological parameters,the crop phenology,and the yield of the soybean crop.The field experiments were conducted during two irrigation crop seasons(2021 and 2022)in Louata,Morocco.The results showed that regulated deficit irrigation regimes during the vegetative stages was combined with high temperatures and low air humidities during the beginning of flowering and the pod filling stage during 2021 in comparison with 2022,especially for 25%CWR(crop water requirements).Regulated deficit irrigation regimes reduced the stomatal conductance by 46%and 52%respectively during the first and second growing seasons by limiting CO_(2) intake for the Calvin cycle.The stomata closure increased the leaf temperature and affected the functioning of the photosynthetic apparatus by damaging the chlorophyll pigments and impairment of electron transport chains in chloroplasts.The transition from regulated deficit irrigation to 100%CWR at the beginning of flowering(R1)compensated for the photosynthetic loss,improved the growth and development of soybean plants and enhanced the yield and its components for 50%and 75%CWR.The adaptative mechanism such as the remobilization of the carbon reserved in the stems and leaves(vegetative tissues)to the grains improved the grain yield by 36.7%during 2021 and by 32.2%during 2022 and.This consequently improved the water use efficiency,the water productivity of soybean for 50%and 75%CWR and contributed to water saving with an average of 60 mm per growing season.展开更多
Effects of continuous negative pressure water supply on water consumption, growth and development, as well as physiological mechanism and quality of Capsicum annuum L. were investigated in this paper. Meanwhile, the o...Effects of continuous negative pressure water supply on water consumption, growth and development, as well as physiological mechanism and quality of Capsicum annuum L. were investigated in this paper. Meanwhile, the optimal negative pressure water supply conditions for growth of C. annuum L. were screened out to achieve the goals of water conservation, high yield and high quality, thus providing theoretical foundation for its field production. The pot experiment within the greenhouse was utilized; the continuous negative pressure water supply was adopted; the four treatments, artificial watering（CK）, –5 k Pa（T1）, –10 k Pa（T2）, and –15 k Pa（T3） were set; and the daily water consumption, yield, as well as the biomass, nitrate reductase, root activity, vitamin C, capsaicin, and nutrient uptakes of nitrogen（N）, phosphorus（P） and potassium（K） during various stages of its growth were determined. Compared with CK, when the water supply pressure was controlled at –5 to –15 k Pa in the experiment, the total water consumption of C. annuum L. reduced by 53.42 to 67.75%, the total water consumption intensity reduced by 54.29 to 67.14%, and the water use efficiency increased by 12.66 to 124.67%. The N accumulation in a single strain of C. annuum L. from the color turning stage to the red ripe stage increased by 15.99 to 100.55%, respectively, compared with that of CK; the P accumulation increased by 20.47 to 154.00% relative to that of CK, and the K accumulation increased by 64.92 to 144.9% compared with that of CK. Compared with CK, C. annuum L. yield was remarkably improved by 13.79% at T1, and contents of vitamin C, capsaicin as well as carotenoids at all growth stages were enhanced by 13.42–147.01%, 11.54–71.01%, and 41.1–568.06%, respectively. Nitrate reductase activity, root activity and chlorophyll（a＋b） were markedly increased by 335.78–500%, 79.6–140.68% and 114.95–676.19%, respectively, from immature stage to full ripe stage. Adopting the continuous negative pressure water supply for C. annuum L. has a significant water-saving effect, and the water supply pressure being stable at –5 k Pa contributes to its growth and development, improves yield, enhances root activity, promotes nutrient uptake, and improves its quality, thus achieving the effects of water conservation, high yield, high quality and high efficiency.展开更多
基金financially supported by Domaine Louata of Providence Verte Company,Agricultural Training and Research Center.
文摘Drought is one of the most severe environmental stresses affecting soybean growth and development,especially in arid and semi-arid areas.The aim of this experiment is to evaluate the effect of regulated deficit irrigation during the vegetative stages on soybean plants and determine the amount irrigation water can be reduced without affecting the physiological parameters,the crop phenology,and the yield of the soybean crop.The field experiments were conducted during two irrigation crop seasons(2021 and 2022)in Louata,Morocco.The results showed that regulated deficit irrigation regimes during the vegetative stages was combined with high temperatures and low air humidities during the beginning of flowering and the pod filling stage during 2021 in comparison with 2022,especially for 25%CWR(crop water requirements).Regulated deficit irrigation regimes reduced the stomatal conductance by 46%and 52%respectively during the first and second growing seasons by limiting CO_(2) intake for the Calvin cycle.The stomata closure increased the leaf temperature and affected the functioning of the photosynthetic apparatus by damaging the chlorophyll pigments and impairment of electron transport chains in chloroplasts.The transition from regulated deficit irrigation to 100%CWR at the beginning of flowering(R1)compensated for the photosynthetic loss,improved the growth and development of soybean plants and enhanced the yield and its components for 50%and 75%CWR.The adaptative mechanism such as the remobilization of the carbon reserved in the stems and leaves(vegetative tissues)to the grains improved the grain yield by 36.7%during 2021 and by 32.2%during 2022 and.This consequently improved the water use efficiency,the water productivity of soybean for 50%and 75%CWR and contributed to water saving with an average of 60 mm per growing season.
基金supported by the National High-Technology Research and Development Program of China (863 Program, 2013AA102900-3)
文摘Effects of continuous negative pressure water supply on water consumption, growth and development, as well as physiological mechanism and quality of Capsicum annuum L. were investigated in this paper. Meanwhile, the optimal negative pressure water supply conditions for growth of C. annuum L. were screened out to achieve the goals of water conservation, high yield and high quality, thus providing theoretical foundation for its field production. The pot experiment within the greenhouse was utilized; the continuous negative pressure water supply was adopted; the four treatments, artificial watering（CK）, –5 k Pa（T1）, –10 k Pa（T2）, and –15 k Pa（T3） were set; and the daily water consumption, yield, as well as the biomass, nitrate reductase, root activity, vitamin C, capsaicin, and nutrient uptakes of nitrogen（N）, phosphorus（P） and potassium（K） during various stages of its growth were determined. Compared with CK, when the water supply pressure was controlled at –5 to –15 k Pa in the experiment, the total water consumption of C. annuum L. reduced by 53.42 to 67.75%, the total water consumption intensity reduced by 54.29 to 67.14%, and the water use efficiency increased by 12.66 to 124.67%. The N accumulation in a single strain of C. annuum L. from the color turning stage to the red ripe stage increased by 15.99 to 100.55%, respectively, compared with that of CK; the P accumulation increased by 20.47 to 154.00% relative to that of CK, and the K accumulation increased by 64.92 to 144.9% compared with that of CK. Compared with CK, C. annuum L. yield was remarkably improved by 13.79% at T1, and contents of vitamin C, capsaicin as well as carotenoids at all growth stages were enhanced by 13.42–147.01%, 11.54–71.01%, and 41.1–568.06%, respectively. Nitrate reductase activity, root activity and chlorophyll（a＋b） were markedly increased by 335.78–500%, 79.6–140.68% and 114.95–676.19%, respectively, from immature stage to full ripe stage. Adopting the continuous negative pressure water supply for C. annuum L. has a significant water-saving effect, and the water supply pressure being stable at –5 k Pa contributes to its growth and development, improves yield, enhances root activity, promotes nutrient uptake, and improves its quality, thus achieving the effects of water conservation, high yield, high quality and high efficiency.
