Computer simulation approaches for rice blast disease forecasting in Japan

Blast disease causes the most serious damage to rice production in Japan. Air temperature and rainfall are known as critical climatic factors that determine the favorable conditions for infection, and hence the severity of blast epidemics. The Japan Meteorological Agency (JMA) has developed an automated meteorological data acquisition system (AMeDAS) which retrieves data. A decision rule model, BLASTAM, has been developed to evaluate the favorable conditions for blast infection of leaves based on AMeDAS data. BLASTAM can identify when and where favorable infection conditions occur on a meso-scale. The purposes of these extension services are not only to provide information about the current and projected situation of local epidemics, but also to recommend topical countermeasures to growers. For the latter purpose, simulation model, BLASTL, of blast epidemics are very useful. With AMeDAS data automatically retrieved from JMA, the Internet-based national network system (JPP-NET) allows the latest information from BLASTAM and BLASTL to be displayed on a Web site.