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通过对１９９８ 年和１９９９ 年草地螟越冬代成虫和一代幼虫，在北方农牧区的发生与分布进行对比分析，说明一、二、三代幼虫，都有可能形成滞育越冬幼虫，成为第二年发生的虫源。据此提出今后要搞好草地螟长期预报，必须跟踪观察各代幼虫越冬的比率和面积大小。
By comparing and analyzing the occurrence and distribution of adult overwintering adults and first-generation larvae of grass larvae in 1998 and 1999 in the pastoral areas in northern China, it is indicated that the first, second and third-generation larvae may form diapause overwintering larvae and become the second year Occurrence of insect sources. Therefore, it is suggested that long-term forecast of meadow rice borer should be carried out in the future. It is necessary to observe and observe the ratio and the area of overwintering generations of larvae.