Molecular Regulatory Mechanism of Exogenous Hydrogen Sulfide in Alleviating Low-Temperature Stress in Pepper Seedlings

作者：Xueping Song, Li Zhu, Dong Wang, Le Liang, Jiachang Xiao, Wen Tang, Minghui Xie, Zhao Zhao, Yunsong Lai, Bo Sun, Yi Tang, Huanxiu Li · 发表于：International Journal of Molecular Sciences · 年份：2023 · DOI：10.3390/ijms242216337 · 被引用次数：16 · 研究领域：Plant Stress Responses and Tolerance、Plant responses to elevated CO2、Plant Molecular Biology Research

Pepper (Capsicum annuum L.) is sensitive to low temperatures, with low-temperature stress affecting its plant growth, yield, and quality. In this study, we analyzed the effects of exogenous hydrogen sulfide (H2S) on pepper seedlings subjected to low-temperature stress. Exogenous H2S increased the content of endogenous H2S and its synthetase activity, enhanced the antioxidant capacity of membrane lipids, and protected the integrity of the membrane system. Exogenous H2S also promoted the Calvin cycle to protect the integrity of photosynthetic organs; enhanced the photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), and photosynthesis; and reduced the intercellular CO2 concentration (Ci). Moreover, the activities of superoxide dismutase, peroxidase, catalase, and anti-cyclic glutathione (ASA-GSH) oxidase were improved to decompose excess reactive oxygen species (ROS), enhance the oxidative stress and detoxification ability of pepper seedlings, and improve the resistance to low-temperature chilling injury in ‘Long Yun2’ pepper seedlings. In addition, the H2S scavenger hypotaurine (HT) aggravated the ROS imbalance by reducing the endogenous H2S content, partially eliminating the beneficial effects of H2S on the oxidative stress and antioxidant defense system, indicating that H2S can effectively alleviate the damage of low temperature on pepper seedlings. The results of transcriptome analysis showed that H2S could induce the MAPK-signaling pathway and plant...