棉蚜体表微生物对弗氏虫霉侵染的影响

THE EFFECT OF SUPERFICIAL MICROBES OF COTTON APHID ON THE GERMINATION AND INFECTION OF ENTOMOPHTHORA FRESENII

对棉蚜体表微生物[芽枝霉(Cladosporium sp.),细菌—8(Bacillus—8)]和弗氏虫霉之间关系的研究结果表明:棉蚜体表微生物对弗氏虫霉[Entomophthora fresenii (Nowak) Gustafs,简称Ef]的孢子萌发、孢子形态变化、侵染力有很大影响。用体表微生物培养液浸Ef孢子能显著提高其萌发率。在Ef菌培养过程中加入体表微生物能产生相似于天然大孢子。将体表微生物和Ef菌剂混合用于田间防蚜,增效作用达29.2％～53.6％。所以笔者认为Ef和棉蚜体表微生物之间有密切的协生关系。

The relationships between germination and infection of Entomophthora fre-senit (Ef) ,one of the important pathogenic fungi found commonly on cotton aphid Aphis gossypii Glover in Shaanxi Province, and some superficial microbes (SM) such as a species of Cladosporium and a bacterium Bacillus-8 collected by the authors, were studied. The results showed that there were significant promotions of SM to Ef. As soaking the spores of Ef in culture solution of SM,its germination rate of spores and infection rate on cotton aphid increased obviously. The Ef culture put with SM was capable to produce big spores similar to the natural ones. 29. 2% - 53. 6% of synerginsms were got by using a mixture of Ef with SM in field trials of cotton aphid control,in comparison with single use of Ef.