球孢白僵菌对月季长管蚜的生物防治效果

研究了1株分离自月季长管蚜(Macrosiphum roswomm Zhang)的球孢白僵菌(Beauveria bassiana(Bals.)Vuill)对月季长管蚜若虫和成虫的致病力及温室防治效果,并对球孢白僵菌孢子在月季叶片上的存活动态进行了深入观测。结果表明:相同条件下,月季长管蚜死亡率随球孢白僵菌孢子浓度的增加而上升,在孢子浓度为108 spores/mL时,月季长管蚜5 d的最高累积死亡率为99.3%; 球孢白僵菌对成虫和3龄若虫的致病性最强,1龄若虫最低。试验发现25 ℃时月季长管蚜死亡率最高,环境湿度越大,月季长管蚜的死亡率越高; 温室内最高感染死亡率达94%,表明球孢白僵菌在月季长管蚜的生物防治中具有很好的应用潜力。
Macrosiphum roswomm is one of the most serious pests on Rosaceae. However, biological control of M.roswomm with Beauveria bassiana still remains unreported. The patho genicity and greenhouse control effect of B.bassiana strain isolated from M.roswomm on aphid nymphs and adults, and the survival of B. bassiana on rose leaves were studied. The results showed that, under the same conditions, aphid mortality increased with increasing spore concentration. At the spore concentration of 108 spores/mL, the highest cumulative mortality was 99.3% in 5 days; the pathogenicity for adults and the third instar nymphs was much higher than the first instar nymph. Under different temperature and humidity, the highest mortality was discovered at the condition of 25 ℃, and the infection mortality rate increased with the increasing of the environment humidity; the highest infection mortality in greenhouse was 94%. These results indicated that B.bassiana has a good potential in biological control of M. roswomm