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本文论述了三个问题,即褐稻虱的发生现况及猖撅原因分析;白背飞虱的发生现状及种群增长原因和两种飞虱今后的发生趋势。在亚洲热带国家,褐稻虱的猖獗时期为六十年代中后期至七十年代中期。猖撅原因,多数人认为与1966年以后广泛推广不抗虫的,矮杆高产品种密切相关;另有部分人认为,改良品种的推广,预计螟虫、叶蝉将会大发生,施用六六六、二嗪农等农药,破坏了天敌的调节作用,引起褐稻虱再猖獗等。在这些国家,白背飞虱是在褐稻虱发生程度减轻的七十年代中期以后,种群数量增加,为害程度逐年加重。分析原因主要是大面积种植抗褐稻飞虱而不抗白背飞虱的品种所致。
This article discusses three issues, namely, the status of the brown planthopper and the reason of its rampant; the current situation of the whitebacked planthopper and its reasons for its population growth and the future occurrence of the two planthoppers. In Asian tropical countries, brown planthopper was rampant from the mid-1960s to the mid-1970s. The reason for the rampant is that most people think it is closely related to the widespread promotion of non-insect resistant and short dwarf high-yield varieties after 1966. Others think that the promotion of improved varieties is expected to occur with stem borers and leafhoppers. , Diazinon and other pesticides, destroyed the regulatory role of natural enemies, causing rampant brown planthopper and so on. In these countries, the number of white-backed planthoppers is increased after the mid-1970s when the occurrence of brown planthopper was reduced, and the degree of harm increased year by year. The main reason for the analysis is the large-scale cultivation of brown planthopper but not white-backed planthopper species.