沈阳地区美国白蛾发生世代及规律的研究

Study on Cohort and Regular of Occurrence for Fall Webworm in Shenyang

2012年～2014年在沈阳地区进行美国白蛾发生规律研究的结果表明，美国白蛾在沈阳1年发生2代，第1代幼虫期为5月下旬至7月中旬，第2代成虫期为7月中旬至8月中旬，卵期7月下旬至8月中旬，幼虫期8月上旬至9月下旬，蛹期9月中旬至次年4月下旬至5月上旬。美国白蛾虫态有重叠现象，1～2代历期不等，第2代成虫产卵期较之第1代明显变短，而幼虫期和蛹期又明显较之第1代变长。

Occurrence regular pattern of fall webworm were studied in Shenyang region from 2012 to 2014 . The result showed that fall webworm occur two generations a year in Shenyang . The first generation larvae begins to see a period of late May to early July .The second generation of adults begins to see in mid-July to mid-August .The egg stage was seen in late July to mid -August and the larval stage appeared in mid -August to early October .The pupal stage were from late September early to late April or May of next year.The instars of fall webworm have phenomenon of overlap .The insect 1~2 generations life period were Unequal , The two generations oviposition period was shorter and larval and pupal period is significantly longer than the generation one .we learn the occurrence and provide the basis for early prevention .