克螨特是一种低毒性杀螨剂,在苹果树上施用防治螨类,效果良好。但是,今年5月间,在我县张邴堡村梨园喷施3 000倍液克螨特加2 500倍液灭百克,用于防治梨树叶螨,并兼治梨木虱。喷药3天后,发现梨的一些品种和株系出现不同程度的药害,主要表现为嫩叶边缘有烧伤的药斑,成叶背面散布黄褐色药斑,正面出现圆形密生枯斑,6天后叶片开始脱落,茌梨叶片脱落率达85％以上,香水梨为8％左右,其他品种无落叶现象。果实上也出现了不规则的条纹状药斑,以香水、长把梨为重,茌梨轻微。6月份,我们又在牟(田仝)姜家村梨园进行了少量试验,结果与张邴堡村梨园相似。另外,我们还发现上午10时前喷药的受害程度轻于10时以后喷药的。因此我们认为,梨园应用克螨特最好先做小面积试验,易受害的品种茌梨应忌用。喷布最好在上午10时前和下午4时后气温较低时进行。 Propargite is a low toxicity acaricide, applied to control apple mites, the effect is good. However, in May this year, in my county Zhangbei Fort pear orchard spraying 3000 times the liquid mites plus 2,500 times the liquid off 100 grams, for the control of pear spider mites, and cure pest. After spraying for 3 days, some varieties and strains of pear were found to have different degrees of phytotoxicity, mainly manifested as burn spots on the edges of young leaves, yellow-brown drug spots scattered on the back of the leaves, and round dense spots on the front, 6 Days after the leaves began to fall off, Pei leaves off rate of 85% or more, perfume Pear is about 8%, no other leaves deciduous phenomenon. The fruit also appeared irregular stripes of drug-like spots, with perfume, long pears as heavy, dizi pear slightly. In June, we conducted a small amount of experiments at Mou (Tian Tong) Lijiayuan, a village similar to Zhangjiapu Village. In addition, we also found that the spraying of pesticides was less than 10 in the morning before 10 o’clock. Therefore, in our opinion, it is advisable to apply a small area test to the pear orchard for the first time, and the susceptible varieties should not be used. Spraying is best done before 10 am and after 4 pm when temperatures are low.