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Rainfall and outbreaks of the African armyworm, Spodoptera exempta (Walker) (Lepidoptera: Noctuidae)

Published online by Cambridge University Press:  10 July 2009

M. R Tucker
Affiliation:
Tropical Development and Research Institute, College House, Wright's Lane, London W8 5SJ, UK
D. E Pedgley
Affiliation:
Tropical Development and Research Institute, College House, Wright's Lane, London W8 5SJ, UK

Abstract

From estimates of the most likely egg–laying dates of 53 outbreaks of Spodoptera exempta (Wlk.) in East Africa, and from estimates of the likelihood of rainstorms (20 mm or more a day) at the outbreak sites around those dates, it is shown that concentrated laying by moths leading to outbreaks early in the season (January to March) in 1974–75 was associated with rainstorms at the time of oviposition. However, there was no such association in April and May. The mechanism of association is unknown; moths may be concentrated whilst airborne, or they may reach and stay in limited areas wetted by rain, where new grass growth might be expected.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 1983

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