Key Laboratory of Eco-environments in Three Gorges Reservoir Region/Engineering Research Center of South Upland Agriculture, Ministry of Education/College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715, China.
Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Environment, Ministry of Agriculture, Beijing 100081, China.
Sci Rep. 2019 Mar 7;9(1):3890. doi: 10.1038/s41598-019-40362-7.
Maize is a sensitive crop to drought and heat stresses, particularly at the reproductive stages of development. The present study investigated the individual and interactive effects of drought (50% field capacity) and heat (38 °C/30 °C) stresses on morpho-physiological growth, yield, nutrient uptake and oxidative metabolism in two maize hybrids i.e., 'Xida 889' and 'Xida 319'. The stress treatments were applied at tasseling stage for 15 days. Drought, heat and drought + heat stress caused oxidative stress by the over-production of ROS (O, HO, OH) and enhanced malondialdehyde contents, which led to reduced photosynthetic components, nutrients uptake and yield attributes. The concurrent occurrence of drought and heat was more severe for maize growth than the single stress. However, both stresses induced the metabolites accumulation and enzymatic and non-enzymatic antioxidants to prevent the oxidative damage. The performance of Xida 899 was more prominent than the Xida 319. The greater tolerance of Xida 889 to heat and drought stresses was attributed to strong antioxidant defense system, higher osmolyte accumulation, and maintenance of photosynthetic pigments and nutrient balance compared with Xida 319.
玉米对干旱和热胁迫敏感，特别是在生殖发育阶段。本研究探讨了干旱（田间持水量的 50%）和热（38°C/30°C）胁迫对两个玉米杂交种“先达 889”和“先达 319”的形态生理生长、产量、养分吸收和氧化代谢的单独和交互影响。胁迫处理在抽穗期持续 15 天。干旱、热和干旱+热胁迫通过过量产生 ROS（O、HO、OH）和增强丙二醛含量引起氧化应激，导致光合成分、养分吸收和产量特性减少。与单一胁迫相比，干旱和热同时发生对玉米生长的影响更为严重。然而，这两种胁迫都诱导了代谢物的积累以及酶和非酶抗氧化剂来防止氧化损伤。与先达 319 相比，先达 899 的表现更为突出。与先达 319 相比，先达 889 对热和干旱胁迫的耐受性更强，这归因于其具有更强的抗氧化防御系统、更高的渗透物质积累以及维持光合色素和养分平衡的能力。
