Abstract:

Downy mildew is the main disease of Vitis amurensis Rupr.We had a further knowledge of downy mildew by many years observation of the downy mildew and the meteorologic conditions of the vineyard.We found that the incubation period of downy mildew was not longer than 24 hours on certain climate conditions,shorter than what people knew before.Meanwhile we found that the abilities of the germ in a certain strain transmited to other strains had marked difference,and so ,we put forward a new idea about how to prevent and cure Vitis amurensis Rupr. downy mildew.