【摘要】 早熟棉花品种２８８ 和中棉所１６ 在第２ 片真叶展开时， 中熟棉花品种中棉所１２ 和鲁棉１４ 在第３～４ 片真叶展开时开始花芽分化。供试４ 个品种在开始花芽分化时主茎顶芽皆出现ＩＡＡ 含量低峰和过氧化物酶活性高峰， 未见ＩＡＡ 氧化酶活性的明显变化。推测棉花花芽分化与ＩＡＡ含量的降低有关， 而ＩＡＡ含量的降低可能是由过氧化物酶活性升高所致。更多还原

【Abstract】 Cotton seedlings of two early matured varieties 288 and CCRI 16, and two later matured varieties CCRI 12 and Lumian14 began floral bud initiation at 2 1eaf stage and 3 or 4 leaf stage, respectively. During the emergence of the first floral primordium, there appeared an evident decrease of IAA, and a peak of POD activity in each of the 4 varieties. However, no evident changes of IAA oxidase activities were found. From the above observation, it was predicted that flower differentiation was related to the decrease of IAA content, which might be resulted from the increase of POD activities.更多还原