泡沫塑料塞孔法施病原线虫防治多纹豹蠹蛾幼虫

1990年在福建室内试验,用芜菁夜蛾昆虫病原线虫北京品系感染多纹豹蠹蛾,按每头豹蠢蛾接线虫500条,5天后即可将幼虫全部杀死。12天后杀死蛹95％。在木麻黄林间试验,线虫剂量均为1000条/毫升,用不同施线虫方法结果,以在蛀孔注入线虫水悬液法和线虫泡沫塑料塞孔法为最好,豹蠹蛾死亡率分别为97和93％,“线虫糊”涂孔法效果为75％。线虫泡沫塑料塞孔法操作简单,省水,省工。在平潭县莲花山林场用线虫泡沫塑料塞孔法处理木麻黄树38000株,豹蠹蛾平均死亡率达90％。

CONTROL OF LEOPARD MOTH, ZEUZERA MULTISTRIGATA LEUCONOTA [LEP.:COSSIDAE] ON CASUARINA TREES BY PLUGGING SPONGE CARRYING STEINERNEMA FELTIAE

Results of the laboratory tests conducted in Fuzhou in 1990 showed that a Beijing strain of Steinernema feltiae, isolated from a dead larva of Holotrichia sp. Col.:Scarabaeidae] in 1986, had high infectivity to Zeuzera multistrigata. an important pest of Casuarina trees (Casuarina equisetifolia) in Fujian. When the leopard moth larvae were exposed to the nematode at 500 juveniles per larva in petri dishes, the larval and pupal mortalities were 100% after 5 days and 95% after 12 days, respectively. In the field experiment carried out in a Casuarina forest, the nematode was applied at 1,000 juveniles/ml with four different application methods. Two methods were found to be most effective. They were direct injection of nematode water suspension into the boring holes and inserting small pieces of synthetic foam sponge soaked with nematode water suspension into the boring holes. The larval mortality of the pest was 97% and 93%. respectively, for the two methods. The "Sponge-plug Method" was found to be easier to operate and required less water and labor compared with other methods. Applying the nematode with the "Sponge-plug Method" in a Casuarina forest of 25.3 ha in 1990 resulted in a 90% average mortality of Z. multistrigata.