Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing, 210037, China.
Planta. 2023 Jul 21;258(3):48. doi: 10.1007/s00425-023-04204-1.
Senescence influences leaf productivity through two aspects: photosynthesis and nutrient remobilization. Through distinctively manipulating progress of leaf senescence, it is promising to improve crop yield and quality simultaneously. Crop yield and quality are two chief goals pursued in agricultural and horticultural production. The basis of crop yield is leaf photosynthesis. Senescence is the last stage of leaf development, which usually causes decreasing of leaf photosynthetic activity. Delaying leaf senescence through physiological or molecular strategies may result in higher photosynthetic activity with a longer duration, thus producing more photoassimilates for biomass accumulation. On the other side, leaf senescence always induces degradation of macromolecular nutrients (including chlorophylls and proteins), and nutritional elements in leaves are then resorbed for development of other organs. For those crops with non-leaf organs as harvested biomass, translocating nutritional elements from leaves to harvested biomass is an indispensable physiological process to increase crop yield and quality. This review summarized successful studies about effects of delaying or promoting senescence on crop yield or quality improvement. Considering the distinctiveness of various crops, manipulation of leaf senescence should be specialized during agricultural and horticultural practices. Rational regulation of leaf senescence, such as inhibiting senescence to maintain leaf photosynthesis and then promoting senescence (with appropriate onset and efficiency) to remobilize more nutrients from leaves to target organs, may ultimately improve both crop yield and quality.
光合作用和养分再利用。通过有区别地调控叶片衰老的进程，有希望同时提高作物的产量和品质。作物产量和品质是农业和园艺生产中追求的两个主要目标。作物产量的基础是叶片光合作用。衰老（senescence）是叶片发育的最后阶段，通常会导致叶片光合作用活性下降。通过生理或分子策略延缓叶片衰老可能会导致更长时间的更高光合作用活性，从而产生更多的光合同化物用于生物量积累。另一方面，叶片衰老总是会诱导大分子营养物质（包括叶绿素和蛋白质）的降解，然后叶片中的营养元素被再吸收用于其他器官的发育。对于那些以非叶片器官作为收获生物量的作物，将营养元素从叶片转移到收获生物量是增加作物产量和品质的必不可少的生理过程。本综述总结了关于延缓或促进衰老对提高作物产量或品质的影响的成功研究。考虑到各种作物的特殊性，在农业和园艺实践中应专门对叶片衰老进行调控。合理调节叶片衰老，例如抑制衰老以维持叶片光合作用，然后促进衰老（具有适当的起始和效率）以将更多的养分从叶片转移到目标器官，最终可能会提高作物的产量和品质。
