Study on overwinterring place and resource of initial inoculums of carrot spotted blight
wang zhi-jiang1; wei sheng-long1; zhang fen-qin2; li jian-jun3(1.institute of edible mushroom; college of hexi; gansu zhangye; 734000; china; 2.department of biology; college of hexi; gansu zhangye; 734000; china; 3.forest pest prevention and quarantine station in zhangye; gansu; gansu zhangye; 734000; china)