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我县四分之三的面积属丘陵山区,作物布局以稻麦两熟为主,中稻占水稻面积的80％以上。多年来,水稻病害造成的损失往往大于虫害,主要有白叶枯病和纹枯病,其次为云形病、叶鞘腐败病、穗颈稻瘟、稻叶尖枯病、稻曲病等。在近14年中,白叶枯病中等及中等以上流行年有8年,特别是1979～1982年连续4年全县每年损失稻谷100万斤左右。纹枯病对株型松散、叶片较宽的品种发病更重,近几年病穴率一般在60％以上。病情指数23.2～45.6。云形病1982年一般病叶率8～26.8％,个别重病田块达43.3％;1983年病叶率9.2～36.7％,个别重病田达70.1％。功能叶发病后,造成减产6.2～18.1％。叶鞘腐败病一般病株率10～30％,个别重病田44.6％,
Three-fourths of the county’s area belongs to the hilly and mountainous areas. The layout of crops is dominated by rice and wheat and middle rice accounts for more than 80% of the rice area. Over the years, the losses caused by rice diseases are often greater than insect pests, mainly bacterial blight and sheath blight, followed by cloud disease, leaf sheath rot disease, panicle blast, rice leaf blight, rice false smut. In the past 14 years, the bacterial blight in medium and over the popular eight years, especially 1979 to 1982 for four consecutive years the county lost about 1000000 pounds of rice each year. Sheath blight on the plant type loose, leaves a wider variety of incidence is more serious in recent years, the rate of disease points are generally above 60%. Disease index 23.2 ~ 45.6. In 1982, the rate of general disease was 8 ~ 26.8%. The number of individual sick diseases was 43.3%. In 1983, the rate of diseased leaves was 9.2% ~ 36.7%, while that of individual severe diseases was 70.1%. Functional leaf disease, resulting in 6.2 to 18.1% reduction in production. Sheath rot disease generally plant disease rate of 10 to 30%, 44.6% of individual severe disease,