College of Agronomy, Shanxi Agricultural University, Taigu, Shanxi, 030801, China.
School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Victoria, 3010, Australia.
Plant Physiol Biochem. 2018 Nov;132:660-665. doi: 10.1016/j.plaphy.2018.10.016. Epub 2018 Oct 12.
Soybean (Glycine max (L.) Merr.) is the world's most important grain legume. The impacts of climate change such as elevated CO and drought on soybean physiological and morphological responses are not well understood. This study evaluated the effects of elevated CO (ambient concentration + 200 mmol mol) and drought stress (35-45% of relative water content) on soybean leaf photosynthesis, chlorophyll fluorescence, stress physiological indexes, morphological parameters, biomass and yield over 2 years at the open-top chamber (OTC) experimental facility in North China. We found that drought decreased intrinsic efficiency of PSII (F'/F'), effective quantum yield of PSII photochemistry (Φ), photochemical quenching coefficient (qP), and yield of soybean, increased nonphotochemical quenching (NPQ), peroxidase (POD), and malondialdehyde (MDA), but had no effect on superoxide dismutase (SOD) or soluble sugar content. Elevated [CO] increased net photosynthetic rate (P), water-use efficiency (WUE), Φ, qP, SOD, soluble sugar content and yield of soybean. Elevated [CO] enhanced the positive effects of drought on WUE, but reduced the negative effects of drought on Φ and qP. Elevated [CO] enhanced the resistance to drought by improving the capacity of photosynthesis and WUE in soybean leaves.
大豆（Glycine max (L.) Merr.）是世界上最重要的粮食作物之一。气候变化如升高的 CO 和干旱对大豆生理和形态响应的影响尚未得到很好的理解。本研究在华北开顶式气室（OTC）实验设施中，通过 2 年的实验，评估了升高的 CO（大气浓度+200mmol/mol）和干旱胁迫（相对水含量 35-45%）对大豆叶片光合作用、叶绿素荧光、胁迫生理指标、形态参数、生物量和产量的影响。我们发现，干旱降低了 PSII 的内在效率（F'/F'）、PSII 光化学有效量子产量（Φ）、光化学猝灭系数（qP）和大豆的产量，增加了非光化学猝灭（NPQ）、过氧化物酶（POD）和丙二醛（MDA），但对超氧化物歧化酶（SOD）或可溶性糖含量没有影响。升高的 [CO] 增加了大豆的净光合速率（P）、水分利用效率（WUE）、Φ、qP、SOD、可溶性糖含量和产量。升高的 [CO] 增强了干旱对 WUE 的积极影响，但降低了干旱对 Φ 和 qP 的负面影响。升高的 [CO] 通过提高大豆叶片光合作用和 WUE 的能力来增强对干旱的抗性。
