How Fecund is Lymantria xylina Swinhoe (Lepidoptera: Lymantriidae) in Taiwan?

臺灣的黑角舞蛾（鱗翅目：毒蛾科）繁殖力有多高？

趙榮台(Jung-Tai Chao) ； 陸聲山(Sheng-Shan Lu) ； 陳一銘(Yi-Ming Chen) ； 莊鈴木(Lin-Mu Jaung) ； 葛兆年(Chao-Nien Koh) ； 葉文琪(Wen-Chi Yeh)

《台灣林業科學》 16卷4期 (2001/12) Pp. 259-266

https://doi.org/10.7075/TJFS.200112.0259

摘要

黑角舞蛾是臺灣本島及其周圍小島為害木麻黃防風林最嚴重的昆蟲之一。本研究之目的在於瞭解黑角舞蛾繁殖力及其卵塊測量價之地理變異，以及卵寄生蜂對黑角舞蛾繁殖力的影響。本研究在臺灣本島西海岸及澎湖等12個防風林總計採集360個黑角舞蛾的卵塊。卵塊之含卵數自180至1,544粒不等，平均為592.5±213.8粒。十二個地點間的卵塊含卵數有顯著差異。卵塊平均長度為36.2±10.3mm，平均寬度為9.3±1.8mm。十二個地點的卵塊大小也有顯著差異。卵塊愈長、愈寬，其中所含的卵數愈多；但是愈長的卵塊愈窄，而愈短的卵塊則愈寬。卵塊附著其上的枝條愈粗，卵塊中的卵粒愈多。大約1/3(122/360)的卵塊受到大蛾卵跳小蜂（膜翅目：跳小蜂科）的寄生。這122個被寄生的卵塊總計羽化855隻大蛾卵跳小蜂。每卵塊平均羽化7.1±6.0隻卵跳小蜂（範圍1-33）。從被寄生卵塊超過10個的6個地點來看，各地卵塊羽化的大蛾卵跳小蜂平均數量並無顯著差異。本文討論了大蛾卵跳小蜂的寄生率0.4%偏低的可能原因。然而，大蛾卵跳小蜂對黑角舞蛾繁殖力的實際影響為何，以及將之作為生物防治之用的潛力如何，仍有待進一步加以評量。

關鍵字

黑角舞蛾 ； 卵塊 ； 繁殖力 ； 大蛾卵跳小蜂

並列摘要

The casuarina moth Lymantria xylina is one of the most damaging pests in the casuarina windbreaks of Taiwan proper and on surrounding islands. This study aimed mainly to understand the fecundity of the casuarina moth, geographical variations in fecundity and in measurements of the egg mass, and the impact of egg parasitoids on the fecundity of this species. In total, 360 egg masses were collected from 12 casuarina plantations along the west coast of Taiwan and on Penghu Island. The number of eggs laid by the female casuarina moth varied from 180 to 1544 per egg mass, with an average of 592.5±213.8. The mean number of eggs per mass varied significantly among sites. The average length of egg masses was 36.2±10.3 mm, and the average width of egg masses was 9.3±1.8 mm. The size of egg masses also varied significantly between sites. The longer the egg mass was, the wider the egg mass was, and the greater number of eggs there were per mass. However, longer egg masses were narrower, while shorter egg masses were wider. Egg masses on larger branches had more eggs. About 1/3 (122/360) of the collected egg masses were attacked by the egg parasitoid, Ooencyrtus kuvanae (Hymenoptera: Encyrtidae). A total of 855 egg parasitoids emerged from these 122 parasitized egg masses. The average number of egg parasitoids emerging per mass was 7.1±6.0. No significant difference in the number of egg parasitoids was found among sites on which more than 10 parasitized egg masses were found. The low rate (0.4%) of egg parasitization by O. kuvanae in this study is discussed. However, the real impact of O. kuvanae on the fecundity of casuarina moth and the potential usefulness of O. kuvanae to control the casuarina moth in Taiwan require further evaluation.

並列關鍵字

casuarina moth ； Lymantria xylina ； egg mass ； fecundity ； Ooencyrtus kuvanae