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1998年我国大部分地区气候异常。长江、松花江流域发生了严重的洪涝灾害,黄河流域及华北大部分地区干旱少雨,加之耕作制度和栽培技术的改变、作物品种更替以及上年病虫越冬基数大等原因,造成病虫灾害频发。总的发生特点是虫害重于病害、稻区重于旱作区、上半年重于...
In most parts of China in 1998, the climate was anomalous. Severe floods occurred in the Yangtze River and Songhua River basins, and the drought and rain in the Yellow River valley and most parts of North China combined with changes in cropping system and cultivation techniques, the replacement of crop varieties and large numbers of pests and diseases over the previous year resulted in frequent occurrence of pest and disease disasters hair. The peculiarities of pests are more serious than diseases, and the area of rice is heavier than that of dry land.