嗜菌异小杆线虫的分离鉴定及生物学特性分析  

Isolation and Identification of Entomopathogenic Nematode and the Analysis of Its Biological Characteristics

作　　者：张红玉[1] 韩岚岚[1] 李冉[1] 赵奎军[1] 程媛[1] 王坤[1] 

机构地区：[1]东北农业大学农学院,哈尔滨150030

出　　处：《中国生物防治学报》2016年第2期196-204,共9页Chinese Journal of Biological Control

基　　金：现代农业产业技术体系建设专项(CARS-04);国家公益性行业(农业)科研专项(201103002)

摘　　要：为了发掘具有耐高温特性的昆虫病原线虫,本实验室对在山东地区采集的122份土样进行了线虫分离,得到异小杆线虫JNR,扩增其ITS基因和D2-D3基因,并构建系统进化树,分析可得:线虫JNR与嗜菌异小杆线虫Heterorhabditis bacteriophora在同一分支,同源性达到98%以上,为嗜菌异小杆线虫品系。为进一步了解该线虫品系的生物学特性,本试验研究了其侵染力、高温耐受力及水平运动能力。结果表明,线虫JNR有较好的耐热性,38℃条件下处理16 h,存活率最高54%,24 h时为32%;40℃水浴处理2 h,低浓度500 IJs/m L下存活率28%,3 h后全部死亡。对大蜡螟和小菜蛾的生测结果显示,在10、15、20、25、30、35、40、60、120、240 IJs/头剂量下处理24 h,蔬菜害虫小菜蛾先出现死亡,大蜡螟则在48 h后出现死亡;大于20 IJs/头剂量下,处理48 h后线虫对大蜡螟的校正死亡率达到59.5%,高于对小菜蛾的侵染效果。在剂量120 IJs/头以上,72 h后寄主的校正死亡率均能达到100%。异小杆线虫JNR在30℃条件下水平运动能力比在18、25℃时强,48 h时有31%的个体运动到3.6 cm处。以上研究表明,该线虫有较强的侵染力,特别是在温度相对较高时具有较好的耐热力和水平运动能力,对防治蔬菜田小菜蛾具有应用开发潜力。In order to discover the heat-tolerant entomopathogenic nematodes, we gathered 122 soil samples from Shandong province and isolated entomopathogenic nematodes named JNR, a strain of Heterorhabditis. After amplified ITS-r DNA and D2-D3 sequence and building the phylogenetic tree, JNR has the closest genetic relationship with Heterorhabditis bacteriophora. The homology was up to 98%. This paper discussed the infectivity, heat tolerance and ability of transverse diffusion of the nematode for biological characteristics. Result shows that JNR has good heat tolerance. At 38 ℃, the survival rate is up to 54% for 16 h while the survival rate was 32% for 24 h; at 40 ℃, the survival rate was 28% for 2 h under 500 IJs/m L while the survival rate was 0 for 3 h. The bio-analysis results showed that Plutella xyllostella begin to die after 24 h under 10, 15, 20, 25, 30, 35, 40, 60, 120, 240 IJs/larvae while Galleria mellonella died after 48 h. The proofreaded mortality（PM） of G. mellonella was up to 59.5% for 48 h under the dosages of 20 IJs/larva or higher. The effect is better than it for P. xyllostella. The PM of hosts was 100% at the dosage of higher than 120 IJs/larva for 72 h. JNR＇s ability of transverse diffusion at 30 ℃ was better than that at 18 ℃ and 25 ℃. There was 31% individuals could move to 3.6 cm in 48 h at 30 ℃. All in all, results indicated that JNR had good capacity of infectivity, heat tolerance（especially at high temperature）, and transverse diffusion, and had the potential of being developed and applied, especially in the control of P. xyllostella.

关 键 词：嗜菌异小杆线虫 分离鉴定 生物学特性 侵染力 耐受力 

分 类 号：S476.15[农业科学—农业昆虫与害虫防治]