Study On Prediction Model Of Plasmopara Viticola

Grape downy mildew, one of the most serious diseases, is harmful to China's grape production. It's the most important event to effectively forecast downy mildew during grape production management. Purpose of this paper was getting an effective way to predict downy mildew, and building a Grape downy mildew early warning system. In this paper, the oospores germination model of plasmopara viticola, the application of artificial neural network in forecasting grape downy mildew, building the grape downy mildew early warning system, the situation of plasmopara viticola oospores germination and the disease prevalence in the past three years were studied in Yangling district, and the results showed:The oospores germination model was accurate in forecasting Oospores germination, and the precision was 85.966 percent. So the model can accurately predict the oospores germination period, and it can be used to guide the control of downy mildew in the course of grape production management.Rainfall period is the most critical period in the course of the control of downy mildew. Rainfall would lead to low temperature and high humidity in summer. The low temperature and high humidity would help to Oospores germination, the first infection and distribution of downy mildew. While we lack of information concerned, rainfall should be believed as the most important fact in prediction.If we want to control the downy mildew well, we must consider the three crucial periods: the oospores germination period, the first infection of downy mildew period and the rainfall period.The model of forecasting grape downy mildew, based on Artificial Neural Network, is precise and effective in forecasting downy mildew. And the precision was 93.554 percent. So, it's available to predict the trend of downy mildew by Artificial Neural Network model. The trend of downy mildew will be predicted effectively.Based on the research of the oospores germination model and the grape downy mildew forecasting model, the Grape downy mildew early warning system was built by the computer program VC++.