中文摘要：

对31个桃品种（系）幼树新梢的叶面喷施外源PBZ和GA3,然后进行3个生长指标（枝条初期生长量、枝条总生长量、节间长度）的调查,对不同桃品种（系）对外源GA3和PBZ的敏感性进行了聚类分析。结果表明：与喷施清水对照相比,外源GA3处理后3个生长指标均值均增大,PBZ处理后3个生长指标均值均减小;特早红、中桃5号、北京9号对外源GA3敏感性较高,春美、大久保等20个品种（系）对外源GA3敏感性较低;永莲水蜜、中农金辉等15个品种（系）对PBZ表现出较高的敏感性,红花山桃、春美等6个品种（系）对PBZ表现出较低的敏感性。

英文摘要：

The leaves of new shoots of 31 peach variety （line） saplings were sprayed by exogenous GA3 and paclobutrazol （ PBZ）, the three growth indexes （ initial shoot growth, total shoot growth, and internode length） of these saplings in different treatments were investigated, and the sensitivity of various peach varieties （lines） to exogenous GA3 and PBZ were studied by clustering analysis. The results showed that： in comparison with the control （spraying with pure water）, the foliar application of exogenous GA3 increased the average values of three growth indexes, while spraying with PBZ decreased the average values of three growth indexes. The results of clustering analysis indicated that： Tezaohong, Zhongtao 5 and Beijing 9 were highly sensitive to exogenous GA3; twenty varieties （lines） including Chunmei and Dajiubao were lowly sensitive to exogenous GA3; fifteen varieties （lines） such as Yonglianshuimi and Zhongnongjinhui had a higher sensitivity to PBZ; six varieties （lines） containing Honghuashantao and Chunmei had a lower sensitivity to PBZ.