Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China; University of Chinese Academy of Sciences, Beijing 100039, China.
Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, China.
Sci Total Environ. 2020 May 15;717:137179. doi: 10.1016/j.scitotenv.2020.137179. Epub 2020 Feb 7.
The Salicaceae family consists of dioecious woody plants. Morphological and physiological species-related, sex-specific responses to nocturnal warming in these plants are seldom-reported. In order to explore the different responses of sex-biased species to nighttime warming, males and females of Populus cathayana and Salix paraplesia were used in this study. After 60 days of nighttime warming (+4 °C ambient nighttime conditions) in growth chambers, nighttime warming significantly (p ≤ 0.05) increased height growth rate, leaf proline content, leaf soluble protein content, and root soluble sugar content, while decreased biomass accumulation, photosynthesis, specific leaf area, and ATP levels in both species. Also, nighttime warming resulted in distorted chloroplasts and a greater starch accumulation in P. cathayana and S. paraplesia leaves. Moreover, sex-specific, nighttime warming responses were different, where P. cathayana males and S. paraplesia females exhibited lower aboveground to root mass ratios and higher root dry mass, net photosynthetic rates, stomatal conductance, total chlorophyll contents, specific leaf area, and lower foliar ATP, and less damage to mesophyll cells compared to the opposite sex. Therefore, P. cathayana males and S. paraplesia females exhibit superior adaptability to nighttime temperatures by enlarging their root systems, accumulating more carbohydrates, and adjusting osmotic substances to support their growth processes. Based on these results, it is predicted that P. cathayana males and S. paraplesia females will outperform the opposite sex under ongoing, rising nighttime temperatures in the future.
杨柳科植物为雌雄异株木本植物。形态学和生理学上的物种相关、性别特异性对这些植物夜间变暖的响应很少有报道。为了探讨性别偏向物种对夜间变暖的不同响应，本研究选用了枫杨和白皮柳的雄性和雌性个体。在生长室中进行 60 天的夜间增温（环境夜间温度+4°C）后，夜间增温显著（p≤0.05）增加了两种植物的株高生长率、叶片脯氨酸含量、叶片可溶性蛋白含量和根可溶性糖含量，而降低了生物量积累、光合作用、比叶面积和 ATP 水平。此外，夜间增温导致枫杨和白皮柳叶片中的叶绿体变形和淀粉积累增加。此外，性别特异性的夜间增温响应不同，枫杨雄性和白皮柳雌性的地上部与根质量比较低，根干质量较高，净光合速率、气孔导度、总叶绿素含量、比叶面积较高，叶片 ATP 较低，且对叶肉细胞的损伤较小。因此，枫杨雄性和白皮柳雌性通过扩大根系、积累更多碳水化合物和调节渗透物质来适应夜间温度，表现出更好的适应性。基于这些结果，可以预测在未来持续升高的夜间温度下，枫杨雄性和白皮柳雌性将优于其相反性别。
