赣榆县是徐淮地区五十年代开始进行大面积旱改水的新稻区,1958年前为无病区.由于种子的大调大运,自流灌区的串灌、漫灌和灌区下游的循环水利用等种种原因,六十年代就沦为白叶枯病的常发病区.七十年代初随着密植、增施氮肥等措施的推广,水稻白叶枯病日趋严重.1972年全县种植42.2万亩水稻,发病面积达30万亩,以致严重减产,单产只有450斤. Ganyu County is a new rice paddy in Xuhuai area that began to make large-scale dryland water reform in the 1950s, and was a disease-free zone before 1958. Because of the major seeding of large seeds, the serial irrigation, flood irrigation and the downstream of irrigated area Water use and other reasons, the 1960s became a common occurrence of bacterial blight in the early seventies with the close planting, the application of nitrogen and other measures to promote the spread of bacterial blight is becoming more serious in 1972 the county planted 42.2 million mu of rice, the incidence of 30 million mu, resulting in a serious cut, yield of only 450 pounds.