Effects of exogenous melatonin on physiology and yield of soybean during seed filling stage under drought stress
Jingnan Zou, Qi Yu, Xijun Jin, Mingyao Wang, Bin Qin, Chun-Yuan REN, Mengxue Wang, Yu-Xian ZHANG
Abstract
<p indent="0mm">Drought stress reduces soybean yield. Exploring the mechanism of improving drought tolerance and reducing yield loss is of great significance for soybean production. Melatonin application can alleviate the growth inhibition and oxidative damage of plants under drought stress. In this experiment, the effects of foliar application of melatonin on photosynthesis, stress resistance, carbon and nitrogen metabolism and yield of soybean during seed filling stage under drought stress were studied in 2017–2018. The application exogenous melatonin increased the antioxidant enzyme activity, inhibited the production of reactive oxygen species, decreased cell membrane damage under drought stress, alleviated the inhibition of photosynthetic capacity by drought stress, improved the carbon and nitrogen assimilation ability, and alleviated the yield loss caused by drought stress. Compared with drought stress, the treatment of melatonin increased the number of pods per plant, the grain number per plant and the hundred grain weight by 2.9%, 0.8%, and 17.2% on average of two years, respectively, and the yield (grain weight per plant) increased by 14.7%.