密植桃树夏季回缩修剪技术研究

Study on Technology of Retraction Pruning in Summer for Dense Planting Peach Trees

主干形和"Y"字形是密植桃树常用的树形。为了避免密植树形主干上的结果枝组过长,必须进行适时回缩。本研究选用三年生桃砧中油13号"Y"字形和主干形植株,进行了二年生枝的夏季回缩修剪强度及回缩时期对其上新梢生长和成花的影响试验。结果表明,在5月中旬,将主干形植株上二年生枝留基部2、4、8个叶丛枝回缩对再发新梢的增粗、增长及成花没有显著差异,再发新梢的成花均较好;在5月中旬和6月中旬对"Y"字形桃树上所有二年生枝留基部2个或3个叶丛枝回缩修剪,再发新梢的成花均较好,但6月中旬回缩后的再发新梢的空节率和单花芽率明显升高,复花芽率有较大降低。

The peach tree structure in cordon shape or in ＇Y＇ shape were mostly adopted in dense planting peach cultivation. In order to avoidfruit shoots on the trunk too long,retraction pruning was commonly adopted. This study chose three-year-old Zhongyou 13 peach trees with the ＇Y＇ orcorden shape tree structure,the effects of retraction time and retraction strength on shoot growth and flower bud formation were studied.The resultsshowed that the retraction pruning treatments at the 2,4 and 8th shoots with leaf bush away from the branch base on the biennial branches for the cordenshape trees in mid-May had no significant difference in growth and flower bud formation for the new shoots on them,and the flower bud formation of thenew shoots were all good for these treatments. The flower bud formation on new shoots were all good too between the retraction pruning treatments inmid-May and mid- June for ＇Y＇ shape trees,but the no bud node rate and the rate of nodes with single bud for the treatment in mid-June were higherthan one in mid-May,and the rate of nodes with multiple flower buds for the treatment in mid-June was lower than that in mid-May.