College of Soil and Water Conservation, Beijing Forestry University, Beijing, 100083, China.
Engineering Research Center of Forestry Ecological Engineering of Ministry of Education, Beijing, 100083, China.
Sci Rep. 2021 Jun 28;11(1):13379. doi: 10.1038/s41598-021-92782-z.
Because of its high flooding tolerance, in recent years, mulberry has become a tree species that is used in plant restoration in impact zones in reservoir areas. Therefore, 3-year-old potted forage mulberry seedlings were used to investigate the mechanism of mulberry adaptation to flooding stress. An indoor simulated flooding method was adopted to study the morphology of mulberry seedling leaves and the changes in leaf chlorophyll fluorescence parameters and fluorescence imaging under different flooding times and depths. The results showed that the leaves of mulberry seedlings treated with shallow submergence remained healthy during the flooding period, while the leaves of mulberry seedlings treated with half submergence and full submergence showed different degrees of waterlogging symptoms in the middle and late flooding periods and formed adventitious roots at the base of the stem. Most of the chlorophyll fluorescence parameters decreased at the beginning of flooding, but the steady-state degree of closure of PS II reaction centres (1-qP_Lss) increased significantly. In the later stage of flooding, the fluorescence parameters showed relatively stable trends. Based on these results, we conclude that mulberry has high flooding tolerance due to a combination of morphological and physiological responses.
由于其较强的耐水淹能力，近年来桑树已成为库区影响带植被恢复的树种之一。因此，本试验选用 3 年生盆栽桑苗，采用室内模拟水淹的方法，研究桑树适应水淹胁迫的机制。研究了不同水淹时间和深度下桑苗叶片的形态以及叶片叶绿素荧光参数和荧光成像的变化。结果表明，在水淹期间，轻度水淹处理的桑苗叶片保持健康，而中度和重度水淹处理的桑苗叶片在水淹中后期表现出不同程度的渍水症状，并在茎基部形成不定根。大多数叶绿素荧光参数在水淹初期下降，但 PSII 反应中心的稳态关闭程度（1-qP_Lss）显著增加。在水淹后期，荧光参数表现出相对稳定的趋势。基于这些结果，我们得出结论，桑树具有较高的耐水淹能力，这是由于其形态和生理响应的综合作用。
