大豆疫霉的土壤诱集检测

DETECTION OF PHYTOPHTHORA SOJAE FROM SOIL WITH SOYBEAN LEAF-DISC BAITING

采用大豆叶碟诱集的方法研究了影响大豆疫霉土壤检测的因素。结果表明，自然感病的风干土壤加蒸馏水湿润至饱和或接的饱和状态，光照条件下预培养４－６ｄ，加５－１０ｍｍ的蒸馏水浸泡，中感病大豆品种的叶碟诱集６－２４ｈ，可以较稳定地检测到大豆疫霉。叶碟诱集后用蒸馏水培养或用选择性培养的检测效果相似但用蒸馏水培养便于检查检测结果，当诱集用的离体叶碟采自含抗病基因的大豆品种的植株时。

The factors concerning of the detection of Phytophthora sojae from soil with soybean leafdisc baiting method were studied. High detection rate of flask and leaf-disc infection ofP. sojae were obtained, when air -dried, naturally infected soybean field soils in flaskwere moistened and pre-incubated under lights at 22~26℃ for 4~6 days, then floodedwith 5~10mm depth excess distilled water, and then baited with soybean leaf-discs for6~24 hours. Distilled water, other than selective medium. was adopted to incubate thebaited leaf-discs. which proved a sensitive technique for the detection of P. sojae. Whenbaiting leaf-discs came from a plant with special resistant gene, only those pathogenswhich can overcome this gene can be baited and detected.