Entomopathogenic nematodes (EPN) are distributed all over the world, and therefore some entomopathogenic nematodes can withstand long cold winter in northern hemisphere. Our objective was to find more resources of EPN of cold tolerance that can withstand overwintering conditions in Heilongjiang Province. Twentynine soil samples were collected from different areas in Heilongjiang Province and EPN were extracted by Galleria mellonella (L.) trap baiting method in 2 samples from Harbin. The prevalence of EPN was 6.9％, which was identified as Heterorhabditis bacteriophora-HBN and H. bacteriophora-ZT. Outdoor investigation showed that the majority of EPN infective juveniles tended to be present at 5 to 15 centimeters below the soil surface during overwintering, where soil temperature was -5 ℃ to -13 ℃ in winter and water content was from (12.9±2.9)％ to (17.3± 1.2)％. In contrast, none of EPN Heterorhabditis bacteriophora NJ strain, an isolate from New Jersey USA as a control group, survived the freezing winter.%为明确我国黑龙江省昆虫病原线虫资源及其越冬情况,在黑龙江省9个县市林下和农田中采集土样分离昆虫病原线虫,并选用从哈尔滨分离的线虫和从美国新泽西引进的昆虫病原线虫进行越冬条件的调查,调查线虫在土壤中越冬深度及土壤温湿度.据不完全统计目前从黑龙江省29份土壤样品中分离得到2个昆虫病原线虫品系,分离频率是6.9%,经鉴定为Heterorhabditis bacteriophora-HBN和H.bacteriophora-ZT.户外调查结果显示侵染期病原线虫在土壤中越冬深度为5～15 cm,土壤温度为-5～-13℃,土壤湿度为(12.9±2.9)%～(17.3±1.2)%.而来自新泽西的对照组线虫在哈尔滨的冬天不能存活.本文调查结果表明在中国最北部黑龙江省有嗜菌异小杆线虫分布,增加了我国昆虫病原线虫资源,扩大了调查地域.
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