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一、年发生世代数及世代的划分我县稻纵卷叶螟,以往一贯认为年发生六代。以4月中、下旬出现的蛾子为第一代,5、6、7、8、9月依次为二、三、四、五、六代。几年来观察,实际年发生八代。在3月中、下旬每年有零生蛾子出现,4月上半月,有小批量的迁入蛾,应算作第一代;在10月下旬至11月上旬,还有一批蛾子出现,并能继续产卵孵化成为越冬虫源,应算作第八代。这样正好和全国统一划分的世代相吻合。
First, the occurrence of generational generation and generational division My county rice leafroll, in the past has always believed that six generations occur. In April, late moths are the first generation, and the fifth, sixth, seventh, eighth, and ninth months are the second, third, fourth, fifth and sixth generations. Observed in recent years, the actual occurrence of eight generations. In mid-March and late-mid-year, zero-born moths emerge each year. In the first half of April, small quantities of migratory moths should be counted as the first generation. From late October to early November, a group of moths appeared and could Continue to spawn hatch become overwintering source, should be counted as the eighth generation. This happens to coincide with the generation of a unified national division.