中国昆虫病原线虫共生细菌的研究概况

RESEARCH ON THE SYMBIOTIC XENORHABDUS BACTERIA ASSOCIATED WITH ENTOMOPATHOGENIC NEMATODES IN CHINA

Steinernema和Heierorhabditis属昆虫病原线虫作为生物防治因子已受到世界各国的广泛重视。这类线虫感染期幼虫肠腔中专化性地携带Xenorhabdus属共生细菌。近年来,明确了Xenorhabdus共生细菌对线虫大量培养的作用,筛选了廉价、方便的线虫人工培养基,从而导致了线虫的商业化生产。自五十年代,特别是七十年代末,我国从捷克斯洛伐克、澳大利亚、美国等地引进了大批Steinernema与Heterorhabditis线虫,同时也从土壤或自然寄主中分离出许多本国线虫种或品系(李丽英 1979;戴冠群 1984;王国汉 1984;刘杰。

This paper attempts to give an outline of the research on Xenorhabdus bacteria associated with entomopathogentc nematodes in their intestines in China. Two bacterial isolates from Guangdong Province were identified to be Chinese strain of X. poinarii. Two non-luminescens isolates (86H1 and X1H3) and a pale pigment-producing isolate X1G12 of X. luminescens were isolated from Guangdong and Hainan respectively. Among seven X. luminescens isolates four groups could be divided on the basis of acceptability as food source by different Heterorhabditis nematode populations. Each nematode strain grows only on some bacterial isolates. This leads support for the existence of subspecies or speeies within X. luminescens. It has been established that both forms of X. luminescens isolates show antimicrobial activities. The spectrum of antibiotic activity suggested that X. luminescens may produce different antimicrobial compounds and that each compound may identify a subspecies of X. luminescens. Influence of Xenorhabdus on the mass production of nematode was carried out. It was reported that on sponge medium the Heterorhabditis nematodes could grow better on the secondary form of some X. luminescens isolates than on the corresponding primary form.