Isolation and identification of the pathogens causing vine stalk and root rot of sweetpotato

摘要

A severe sweetpotato disease damage was found in several district of Guangdong(GD)provinces during 2006 and 2007.Three typical symptoms of vine stalk expansion,vine stalk rot and tuberous root rot were observed on the disease infected plants.In order to isolate the pathogen fungus,ten sampies of the disease infected plants were collected from Guangzhou and Haifeng in GD province.Two typical pathogenicity of pathogen fungus were isolated from these samples by the standard means of the Kochs Postulation and uniform symptoms were showed from inoculation test.Classify search indicated that this disease was caused by the ascomycete Nectria (anamorph：Fusarium).It was temporarily named as sweetpotato vine stalk and root rot (SPVSRD) base on the symptoms and pathogens characteristics of this disease and further confirm study on the pathogens characteristics and epidemic of diseases should be carried out.