多效唑对8种经济树种生长和结果的调控作用

对桃、李、梨、栗和银杏等８种水果和干果树种不同施用方法施以不同浓度的多效唑。结果表明多效唑对这８个树种的生长均有不同程度的抑制作用，新梢变短，叶面积缩小。桃抑制程度最为强烈；李和梨较为缓和，抑制作用较弱；栗强烈反应出现在第２年。多效唑可促进桃和李花芽形成。桃幼树施用多效唑后坐果率下降，但成年桃和梨坐果率提高。树种间抑制作用开始、持续和消失时间各异。抑制作用消失后，后期出现补偿生长，年生长量增加。因

Effect of PP_(333)on Growth and Fruiting for 8 Species of Economic Trees

PP333 at different concentrations was used in 8 economic species of trees sucha as peach, plum, chestnut and ginkgo in different ways.Results showed that PP333, to various extents,had some retardant effect on elongation of new growth and enlargement of leaf area in these 8 species,especially in peach followed by plum,pear and chestnut trees.In chestnut,the effect was very obvious on new growth in the 2nd year of zeatment.Floral bud form-ation was acce lerated in peach and plum with the treatment of PP333,so was fruit set in adult peach trees,which was opposite to what was observed in young peach trees.In addition,appearance,disappearance and duration of retardant effect of PP333 proceeded at the different time among species.Compensating growth usualy followed disappearance of the retardant effect at the time of early growth.For some species,PP333 came to effect only by increasing con-centration or by increasing times of treatment.