香梨果实成熟衰老过程中4种内源激素的变化

以库尔勒香梨白梨(PyrusbretschneideriRehd.)的变种]为材料，在果实生长发育、成熟衰老期间检测内源IAA、GA3、ABA、乙烯含量变化规律及其相互关系。结果表明果实发育初期IAA、GA3、ABA含量最高，有利于幼果坐果；CA3与ABA的比值变化对果实迅速膨大起关键作用；高浓度GA3对阻抑叶绿素分解起明显作用；果实成熟衰老期间，IAA含量与乙烯释放速率呈方向相同的变化；在此期间GA3含量变化与乙烯释放变化相反。

Changes in Content or Release Rate of 4 Kinds of Plant Hormones in Relation to the Development, Ripening and Senescence of Fragrant Pear Fruit

Changes in endogenous IAA,GA 3 and ABA contents and release rate of ethylene of fragrant pear a variety of bretschneider pear (Pyrus bretschneideri Rehd.)] fruit and the interrelations between 4 kinds of plant hormones were studied during fruit development, ripening and senescence. It was shown that IAA,GA 3 and ABA contents were highest during the early period of fruit development (Fig.2), which favored fruit set. The changes in ABA/GA 3 rate seemed to be the key factor in determining fruit expansion (Fig.3).High GA 3 content obviously inhibited the decomposion of chlorophyll (Fig.2); At the period of fruit maturity, the change in IAA content and the ethylene release rate were along the same direction, the change in GA 3 content was negativly correlated with the ethylene release rate (Fig.5).