| Zhejiang province, which has biggest plant area of vegetable soybean, is the biggest produce and process base of vegetable soybean in china. Taiwan75, which is good quality and high yield, was transferred and planted from Taiwan to Zhejiang province in 1994, and was the unique variety require to export by foreign merchant. Up to the present, there is no other variety can replace the Taiwan75. In the summer of 2001, a kind of brown stria-like lesion, much like mechanical nick, was observed on the pods of vegetable soybean Taiwan75 ,which was the leading variety planted in the zhejiang province, the rates of diseased plants and infected pods were 50% and 30% in the field on average, in the serious diseased field, which can be more than 90%and 50%, so the pods' mercantile worth was seriously affected.Isolation, identification of pathogen and pathogenicity tests showed that, brown stria-like lesion was caused by Colletotrichum truncatum (Schwein) Andrus & W. D. Moore. Isolate XST01 was isolated from diseased pods. There were 2 types of symptom on the taiwan75's pods, which inoculated with XST01, one type is stria-like and irregular lesions, and the other type is round blotch, the pathogens isolated from two types of symptoms, have same morphological characters and rDNA ITS sequences. The same pathogen on the different soybean varieties, have different symptoms: stria-like and irregular lesions were mainly on the Taiwan75, on the other 6 tested varieties, round blotches were mainly symptoms. On the some varieties, such as Qinshu2hao, Yindou9701, there were few stria-like and irregular lesions be found on them.The result of our study showed that, the brown stria-like lesions, which ever were mistaken for mechanical nick, were caused by C. truncatum, and were one symptom type of soybean anthracnose. To our knowledge, this is the first time research about brown stria-like lesions, and also is the first time research in detail about pathogens and symptoms of soybean anthracnose.It is sure that the main factors, which affect disease indexes of soybean pod Anthracnose, were temperature, humidity and rainfall .etc. high temperature in the phase of flowering, fruiting and pod-plumping, high humidity in the phase of pod-plumping ,the high rainfall in whole of phases of soybean growing, will lead to a high disease index.what's the effective fungicide for prevention and control was found out, what's the available time for prevention and control was maken clear, and formes a set of systematic control techniques. Namely, adjusting the seedtime properly, to make the period of duration which soybean usually got sick avoid the suitable temperature and high humid influence as far as possible. At the year when disease commonly occurred (the year with few rainy days at flowering and podding stages of soybean) , fungicide was applied each time in blooming and full blooming period; At the year when disease severely occurred (the year with lots of rainy days at flowering and podding stages of soybean) , fungicide was applied each time in blooming, full blooming and pod setting period, it means apply fungicide 3 times continuously in every week; Take Topsin-M 70% W.P.as the first choice medicament, and take turns to use 25% 'Bao Xian Ke' EC, 43% 'Hao Li Ke' SC, 60% 'Bai Tai' DC, 10% 'Shi Gao' WG, 20% 'Hao Liang' WP and so on.
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