李裂果病防治研究

为了研究有效防止李（Prunus salicina L.）裂果问题，从乙烯利抑制果实水分超量吸收和GA₃促进表皮增长角度入手，筛选试剂及其浓度、组合、剂量和施用时期最佳组合，比较各处理组合果实内物质含量及果皮细胞结构差异。采收前30 d左右，向果实均匀喷布0.5 g · L^-1乙烯利，第2天再用0.5 g · L^-1 GA₃喷布1次，此处理组合裂果率仅为0.4%（对照21.2%），防治效果98.13%，果实可溶性糖、维生素C含量极显著高于对照，可滴定酸、含水量极显著低于对照。对照的表皮细胞很小，下皮层个别细胞很大，生长速度不同步是导致果皮胀裂的原因。乙烯利可减少果实水分，使下皮层细胞横向变窄小，并由纵向长条形变为横向长条形排列，果皮不易纵向开裂。GA₃使表皮细胞明显增大。乙烯利与GA₃配合施用，使表皮和下皮层两部分细胞同步增长。单独使用乙烯利易引起落果，降低果实含糖量，结合使用GA₃可防止落果，增加含糖量。

Studies on Prevention of Plum Fruit Cracking Disease

For the purpose of effectively prevent plum fruit（Prunus salicina L.）cracking disease，suppress the fruits of moisture absorption and GA₃ promote epidermal growth angles from ethephon. The optimum combination of the screening reagent concentration，composition，dosage and administration period，comparing each treatment differences matter content in the combination of fruit and peel the cell structure. Thirty days before harvest，painstaking sprayed ethephon（0.5 g · L^-1）one time，then sprayed GA₃（0.5 g · L^-1）one time the day after. After this，the results shows that the cracking rate is only 0.4%（control 21.2%）and control efficiency is 98.13%. The contents of soluble sugar and vitamin C are significantly higher than the control group. Titratable acid and water content are significantly lower than the control group. The core reason of peel splitting is that the compared epidermal cells is relatively small and several cells in the cortical is relatively great and the growth rates are not synchronized. By reducing moisture，using ethephon could be narrow under cortical cells，and translate into a horizontal strip from a vertical strip while the longitudinal cracking of skin is not easy. GA₃ significantly increase the epidermal cells. Due to reducing water content，the epidermal cells and under cortical cells are increasedsimultaneously. Using ethephon alone could lead premature fruits drop and reduce the sugar content of fruits. With combination of GA₃，premature fruits drop can be prevented and sugar content can be increase.