Mechanism of Resurgence of the Diamondback Moth, Plutella xylostella (L.) (Lepidoptera: Yponomeutidae)

JARQ : Japan Agricultural Research Quarterly
ISSN 00213551
書誌レコードID(総合目録DB) AA0068709X

The role of predators and parasites was evaluated by artificially excluding them for the estimation of the DBM mortality. The results showed the importance of ground-dwelling predators such as the lycosid spider which was a major biotic mortality agent of DBM at immature stages based on an immunological test; the incidence of this spider decreased by the application of methomyl. The LC50 of the lycosid Pardosa astrigera was around 10 ppm against about 7,500 ppm for the fourth instar DBM larvae using the dipping method and about 20,000 ppm for third instar larvae by feeding methomylcontaminated cabbage leaves. Applications of sublethal concentrations of methomyl to fourth instar larvae and pupae of DBM resulted in the increase of the fecundity of the adults which emerged. The adult females derived from the treated pupae laid a larger number of eggs with a higher rate of fertilization than the untreated check. The application of methomyl thus may actually cause a resurgence of the insect population through the following mechanisms: (1) insecticide resistance, (2) differential mortality levels between DBM and its predator which is a major factor in the control , and (3) stimulation of the reproductive potential.

作成者 Hisashi NEMOTO
国立情報学研究所メタデータ主題語彙集(資源タイプ) Journal Article
開始ページ 27
終了ページ 32
言語 eng