Fu Xiaowei, Zhao Xiaoyang, Xie Bingtang, Ali Abid, Wu Kongming
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, P.R. China.
J Econ Entomol. 2015 Apr;108(2):525-38. doi: 10.1093/jee/tov019. Epub 2015 Mar 15.
The common cutworm, Spodoptera litura (F.), is a serious crop pest with a strong migratory ability. Previous studies on the migration of S. litura were mostly carried out in its "year-round breeding region" (YBR) or "overwintering region" (OR). However, the pattern of seasonal movements in its "summer breeding region" (SBR; i.e., northern China where they cannot overwinter) remains unknown. Here, we present data from an 11-yr study of this species made by searchlight trapping on Beihuang (BH) Island in the center of the Bohai Strait, which provides direct evidence that S. litura regularly migrates across this sea. There was considerable yearly and monthly variation in the number of S. litura trapped on BH, with the vast majority trapped in the autumn. The mean time from the earliest trapping to the latest trapping within a year was 110±12 d during 2003-2013, with the shortest time span of 40 d in 2003 and the longest of 166 d in 2012. S. litura moths had downwind displacement rather than randomly by heading toward their seasonally favorable direction (i.e. toward southwest in the four autumn migration events by prevailing northeasterly winds). Some females trapped in July showed a relatively higher proportion of having mated and a degree of ovarian development, suggesting that the migration of this species is not completely bound by the "oogenesis-flight syndrome." These findings provide a good starting point of research on S. litura migration between its OR (or YBR) and SBR, which will help us develop more effective regional management strategies against this pest.
斜纹夜蛾（Spodoptera litura (F.)）是一种具有很强迁飞能力的严重作物害虫。以往关于斜纹夜蛾迁飞的研究大多在其“全年繁殖区”（YBR）或“越冬区”（OR）进行。然而，其“夏季繁殖区”（SBR，即中国北方，它们无法在此越冬）的季节性迁飞模式仍不清楚。在此，我们展示了一项在渤海海峡中部的北隍（BH）岛进行的为期11年的灯光诱捕研究数据，该数据提供了斜纹夜蛾定期飞越这片海域的直接证据。在BH岛诱捕到的斜纹夜蛾数量存在显著的年度和月度差异，绝大多数在秋季被捕获。2003 - 2013年期间，一年内最早诱捕到最晚诱捕的平均时间为110±12天，2003年最短为40天，2012年最长为166天。斜纹夜蛾成虫顺风迁飞，并非随机飞行，而是朝着其季节性适宜方向（即在四次秋季迁飞事件中，在东北风盛行时朝着西南方向）。7月捕获的一些雌蛾显示出相对较高的交配比例和卵巢发育程度，这表明该物种的迁飞并不完全受“卵子发生 - 飞行综合征”的限制。这些发现为研究斜纹夜蛾在其越冬区（或全年繁殖区）与夏季繁殖区之间的迁飞提供了良好的研究起点，这将有助于我们制定更有效的针对该害虫的区域管理策略。
