Mechanism of drought tolerance of regume

豆科作物的叶片衰老往往伴随着籽粒的灌浆和成熟，因为营养物质从源器官到库器官的有效转运是高产的必要条件。脱荚处理抑制了豇豆生殖期叶片的衰老。生殖期干旱胁迫对豇豆叶片衰老和种子成熟均有促进作用。干旱胁迫还会使叶片糖含量短暂升高，进而显著促进叶片向种子的糖转运。这些结果表明，叶片衰老受叶片、茎和豆荚等器官间糖转运状态的影响。结果表明，自噬相关基因（ATGs）参与了豇豆叶片衰老过程，该过程首先受糖营养调控。此外，活性氧处理提高了大豆叶片的抗旱性。

Leaf senescence of legume crops is often accompanied with the grain filling and maturation at the reproductive stage, because efficient nutrient translocation from source organs to the sink organs is essential for high yield. The leaf senescence of cowpea at the reproductive stage was suppressed by depodding treatment. Drought stress on cowpea at the reproductive stage enhanced both leaf senescence and seed maturation. Drought stress also transiently increased sugar contents in leaf and then significantly enhanced sugar translocation from leaves to seeds. These results suggest that the leaf senescence was affected by a status of sugar translocation among organs such as leaves, stems, and pods. It was indicated that autophagy- related genes (ATGs) was involved in leaf senescence of cowpea firstly regulated by sugar nutrient. In addition, ROS treatmenttoleaves enhanced drought tolerance of soybean.