微孢子虫饵剂的不同配方对新疆草原蝗虫的防治效果

EFFECS OF THE CONTROL OF GRASSHOPPERS IN X INJIANG RANGELAND BY USING NOSEMA LOCUSTAE BRAN BAIT WITH DIFFERENT FORMULATION

在新疆用微孢子虫对３种草原蝗虫进行室内感病性试验，结果不同种蝗虫的感病率差异很大，红胫戟纹蝗的感病率高达８３．５％，而意大利蝗和西伯利亚蝗仅分别为３４．５％和１７．７％。用飞机在草原喷洒，微孢子虫饵剂每１００克加５０％马拉硫磷４ｍｌ和１０ｍｌ，对意大利蝗和红胫戟纹蝗虫口减退率可增加到７６．７％和７６．０％，明显高于单用微孢子虫饵剂的杀虫效果。作者认为在一般蝗虫发生年份，单用微孢子虫饵剂可压低虫口到防治指标（１０头／ｍ２）以下，蝗虫发生量大的年份，采用加微量农药的微孢子虫饵剂，既可提高防效。

Experiments were conducted to study the susceptibility of 3 species of rangeland grasshopper to Nosema locustae in Xinjiang. Result showed the susceptibili ty of Dociostaurus kraussi was 86.3%, but that of Caliiptamus italicus a nd Gomphocerus sibiricus were 34.5% and 17.7% only. Adding 4 ml of 50% mala t ion to 100g Nosema locustae bran, the rate of population reduction of Cali iptamus italicus was 76.7%, which was much higher than that of using Nosema locustae alone. It seems that in a moderate grasshopper year, only applying Nosema locustae bran would suppress the population density under the control i ndex (10 head/m 2). But, in the years of grasshopper outbreak, Nosema locusta e bran should be mixed with small dosage of insecticide tp improve the control effect.