Blast is one of serious obstacles for agricultural production in Vietnam as well as other countries. The emergence and development of the disease depends rapidly on some factors, such as: the influence of soil, fertilizer, chemical fungicides and characteristics of rice cultivars. The results showed that current cultivation status of the three investigated areas in both 2008-2009 and 2009-2010 Winter-Spring crops differed from each other. The use of fertilizers among the rice growing areas were different, the dosage of fertilizer used by most farmers in the areas was not following by recommendation of producer, with a low level comparing with the recommended dosage. Significant blast took place in Quang Loi and the average yield obtained in this area reached the lowest (-2,1 quintals per 500m2). Therefore, type of soil and structure of rice cultlvars, fertilizer have a significant impact to the situation of blast and yield of rice.Beam 75WP and Fuji-one 40EC were used popularly to prevent of blast epidemic, 59.7 percent (2008-2009), 58.8 percent (2009-2010) of Beam 75WP and 38.5 percent (2008-2009), 39.4 percent (2009-2010) of Fuji-one 40EC. They were utilized in the heavy blast epidemic areas more than others. Assessing directly of blast on the field illustrated that the disease appeared popularly on 13/2 and Xi23 cultivars, especially
13/2 cultlvar was a heavy susceptible to blast disease. In addition, the blast only appeared sparsely on Khang dan, HT1, N97 cultivars. Moreover, the authors also compared the blast resistance of rice cultlvars between three areas through the survey. The blast resistance of rice cultivars in different areas were not the same.