西维因是果树化学疏花疏果比较理想的药剂之一。其施药期,正值梨蚜大量发生期,采用适宜浓度的西维因疏果如能同时兼治梨蚜,则对降低果树管理费用,提高果园经济效益,有很大的意义。为此,1982年我们利用所内试验区,对梨蚜的防治效果进行了田间及室内观察。现将结果总结如下。试验方法供试梨树品种为鸭梨、秋自梨(4年生),生长发育正常。药剂为西维因(25%可湿性粉 Xiweidin is one of the more ideal chemical agents for fruit tree thinning and thinning. Its application period is at a time when there are a large number of occurrences of pear aphids. It is of great significance to reduce costs of fruit tree management and increase the economic benefits of orchards by using suitable concentrations of Xylomephan. To this end, in 1982 we used the experimental area, the pear aphid control effects were field and indoor observations. The results are summarized below. Test methods pear varieties for the test pear, autumn from pear (4-year-old), normal growth and development. The agent is Cimetidine (25% wettable powder