【摘要】 【目的】为完善湿热产区梨早期落叶综合防控技术措施,探讨植物生长抑制剂对梨叶部病害及早期落叶与二次开花的影响。【方法】以5年生‘翠冠’梨植株为试材,通过叶面喷施多效唑、华叶牌PBO、氟硅唑、丙环唑、磷酸氢二钾5种化学制剂及清水对照处理,调查分析梨梢叶生长及叶部病害、早期落叶、二次开花发生情况。【结果】与对照相比,5种化学制剂对梨梢生长均具一定的抑制作用,由强至弱依次为:多效唑>PBO>氟硅唑、丙环唑>磷酸二氢钾,新梢停长分别提早27.8、15.2、19.4、18.8、11.5 d;对叶生长多效唑表现显著或极显著的促进作用,其他处理表现不同程度的抑制作用。不同处理对叶部病害、早期落叶、二次开花发生具有显著或极显著的延缓和减轻作用,不同阶段4种主要叶部病害病情指数由低至高依次为:氟硅唑<PBO<丙环唑<磷酸氢二钾<多效唑;控制早期落叶作用强弱依次为:氟硅唑>PBO、丙环唑>磷酸氢二钾>多效唑,大量落叶期分别推迟25、22、20、15、12 d。【结论】化学控梢作为梨保叶保花配套技术措施以选择功能复合制剂(PBO)效果为好。更多还原

【Abstract】 【Objective】 Effects of spraying plant growth inhibitors on the leaf diseases, early defoliation and reflorescence of pear trees were studied for improvements on prevention and control of the commonly occurred defects on pear trees in areas under hot and humid conditions. 【Method】Five-year-old Cuiguan pear trees were sprayed with one of the 5 plant growth inhibitors or water(control) to observe the effects on the growth of shoots and leaves as well as the occurrence of leaf diseases, early defoliation and reflorescence. 【Result】 The chemicals applied controlled the growth of shoots in varying degrees ranking in the order of paclobutrazol>PBO>flusilazole>propiconazole>monopotassium phosphate. These inhibitors stopped shoot elongation 27.8 d, 15.2 d, 19.4 d, 18.8 d and 11.5 d, respectively, sooner than did control. On the leaves, paclobutrazol stimulated their growth, while the other chemicals exerted varying degrees of inhibitory effect on the growth. All inhibitors either significantly or extremely significantly alleviated the leaf diseases or delayed the early defoliation and reflorescence. The indices on 4 major diseases in various periods after treatments ranked in the order of flusilazole<PBO<propiconazole<monopotassium phosphate<paclobutrazol. The control effect of the inhibitors on early defoliation were in the order of flusilazole>PBO>propiconazole>monopotassium phosphate>paclobutrazol. The defoliation was delayed 25 d by flusilazole, 22 d by PBO, 20 d by propiconazole, 15 d by monopotassium phosphate, and 12 d by paclobutrazol. 【Conclusion】 Chemical control could be effective for leaf and flower retentions of a pear tree. Spraying combined agents might produce better effect.更多还原