小麦苗期发育可用数量表示,植株上叶和分蘖上叶的发育均可用Haun’s(1973)方法计算(Klepper等,1982)。未受胁迫的植株叶片和分蘖按照一个固定的形式产生。这种固定形式由两个因素决定:1.分蘖叶的延伸与主茎的发育时间有关;2.根据相同的成叶期间隔估算植株茎秆上叶片的产生。成叶期是指 The number of seedlings available for development in wheat shows that the development of the upper leaves and the upper leaves can be calculated by Haun’s (1973) method (Klepper et al., 1982). Undisturbed plant leaves and tillers are produced in a fixed form. This fixed form is determined by two factors: 1. The extension of tillering leaves is related to the development of the main stem; 2. The production of leaves on the stalk of the plant is estimated on the basis of the same leafing interval. Into the leaf stage is