Sufficient nitrogen nutrition could improve the contents of soluble protein and nucleic acid in flag leaf and reduce the activities of protease and nuclease, and delay the senescence of plant.

• 氮素营养充足可以提高旗叶可溶性蛋白质和核酸含量 ,降低蛋白酶和核酸酶活性 ,从而延缓小麦旗叶的衰老。