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随着农业种植结构的调整,耕作方式的改变和社会经济活动的变化,作物相更加多样化,各作物茬口关联更紧密,人为的影响加剧。河北省农作物病虫害发生与20世纪90年代前相比发生了很大变化,仅2005年就有许多新的种类或新的表现。为了研究、掌握新病虫发生动态及其发生规律,及时科学
With the adjustment of agricultural planting structure, changes in farming practices and changes in socio-economic activities, crop diversification is more diversified, and crop rotation is more closely linked and human-induced effects are aggravated. The occurrence of crop pests and diseases in Hebei Province has greatly changed from that of the 1990s before the 1990s. In 2005 alone, there were many new species or new manifestations. In order to study, grasp the dynamics of new diseases and pests and its occurrence, timely science