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一、水稻害虫的类型据记载:水稻害虫有200多种.其中约有95%以上的种类,由天与自然天敌相处在一个既相互制约又相对稳定、且不超过其经济允许受害水平的低密度状态下;所以我省常见的一些水稻害虫随其生活环境的不司而表现出地区间、年度间和季节间所发生的范围和危害程度的较大差异.二、我省水稻害虫的演变及其原因解放以来,随着我省耕作制度的改变和载培技术与管理水平等的不断提高,水稻害虫的演变可分三种类型.
First, the type of rice pests It is documented that there are more than 200 kinds of rice pests, of which about 95% or more of species, by the natural and natural enemies in a mutually restrained and relatively stable, and does not exceed its economic allowable level of victimization Density, so some pests in our province common with their living environment and show the inter-regional, annual and seasonal differences occurred between the scope and degree of harm greater.Second, the evolution of rice pests in our province Since the liberation of its causes and with the continuous improvement of farming system in our province and the continuous improvement of the techniques and management of cultivation and cultivation, the evolution of rice pests can be divided into three types.