Institute of Plant Genetics, Polish Academy of Sciences, Strzeszyńska 34, 60-479 Poznań, Poland.
Department of Plant Ecophysiology, Institute of Experimental Biology, Faculty of Biology, Adam Mickiewicz University, 61-614 Poznań, Poland.
Int J Mol Sci. 2020 Apr 30;21(9):3174. doi: 10.3390/ijms21093174.
Impact of photosynthetic and antioxidant capacities on drought tolerance of two closely related forage grasses, and , was deciphered. Within each species, two genotypes distinct in drought tolerance were subjected to a short-term drought, followed by a subsequent re-watering. The studies were focused on: () analysis of plant physiological performance, including: water uptake, abscisic acid (ABA) content, membrane integrity, gas exchange, and relative water content in leaf tissue; () analysis of plant photosynthetic capacity (chlorophyll fluorescence; gene expression, protein accumulation, and activity of selected enzymes of the Calvin cycle); and () analysis of plant antioxidant capacity (reactive oxygen species (ROS) generation; gene expression, protein accumulation and activity of selected enzymes). Though, and revealed different strategies in water uptake, and partially also in ABA signaling, their physiological reactions to drought and further re-watering, were similar. On the other hand, performance of the Calvin cycle and antioxidant system differed between the analyzed species under drought and re-watering periods. A stable efficiency of the Calvin cycle in was crucial to maintain a balanced network of ROS/redox signaling, and consequently drought tolerance. The antioxidant capacity influenced mostly tolerance to stress in .
解析了两种密切相关的饲用草（ 和 ）的光合和抗氧化能力对干旱胁迫耐受性的影响。在每个物种中，选取了两个耐旱性有明显差异的基因型进行短期干旱胁迫处理，随后进行复水。研究重点在于：（i）分析植物生理性能，包括：水分吸收、脱落酸（ABA）含量、细胞膜完整性、气体交换和叶片组织的相对含水量；（ii）分析植物光合作用能力（叶绿素荧光；基因表达、卡尔文循环选定酶的蛋白积累和活性）；（iii）分析植物抗氧化能力（活性氧（ROS）产生；基因表达、卡尔文循环选定酶的蛋白积累和活性）。尽管 和 在水分吸收方面表现出不同的策略，并且在 ABA 信号转导方面也有部分差异，但它们对干旱和复水的生理反应是相似的。另一方面，在干旱和复水期间，分析的物种之间卡尔文循环和抗氧化系统的性能存在差异。在 中，卡尔文循环的稳定效率对于维持 ROS/氧化还原信号的平衡网络以及干旱耐受性至关重要。抗氧化能力主要影响 对胁迫的耐受性。
