Abstract: Michelia alba, with a high height and few flowers in blooming period, is not good for cultivation in house. To overcome these disadvantages, Michelia alba were treated with paclobutrazol and ABA in various ways, such as soil application, foliage spraying, and used to detect the height, blossom condition, phytohormones concentrations and photosynthetic efficiency in different positions of plant. The results showed that the concentration of phytohormones, such as IAA, GA3, Z, ZR and ABA,displayed different regularity of change, and the photosynthesis rate changed obviously after treatments. The plants treated was short and small, flowering early, and the amount of flowers and flowering frequency increased. Soil application and foliage spraying of paclobutrazol and ABA were found the best way to dwarf the height of Michelia alba to 40%～50% of CK, and increase the amount of flowers 2.3 times of CK.

Key words: Michelia alba, paclobutrazol, ABA, blossom, photosynthetic rate

摘要： 以白兰花为试材，采用土施、喷施多效唑和脱落酸的方式对其植株进行处理，观察株高和开花情况，同时结合主要内源激素含量及光合特性进行分析。结果表明：经处理后，白兰花内源激素IAA、GA3、Z、ZR和ABA含量呈现不同的变化规律，且光合速率也出现明显的变化；经处理后的植株明显矮化，盛花期提前，开花数量大幅度增加，且开花次数也显著增多。其中以土施和喷施多效唑与脱落酸的效果最好，处理后的植株只有正常株高的40%～50%，开花数却达到正常植株的2.3倍。

关键词: 白兰花, 多效唑, 脱落酸, 内源激素, 光合特性