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Behavioural ecology of the african armyworm, Spodoptera exempta (Walker): Observations on population processes during a high-density outbreak

Published online by Cambridge University Press:  19 September 2011

Syed Khasimuddin
Affiliation:
The International Centre of Insect Physiology and Ecology (ICIPE), P.O. Box 30772, Nairobi, Kenya
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Abstract

During sporadic outbreaks of S. exempta, population densities sometimes reach extremely high numbers. Monitoring at one such outbreak revealed that a considerable synchrony exists in the developmental processes of such populations, so that at times up to 97% of the population is represented by only one stage of development. Heavy pupal mortality with symptoms of a cytoplasmic virus infection was noted. Flight behaviour of emerging adults revealed observable differences in the flight activity of the moths. Although a great majority of the emerging moths flew away from the area, some stayed back. Eggs layed by the latter produced a second brood but, due to a more or less total depletion of the food source, this subsequent brood did not survive in any appreciable numbers and finally died out.

Type
Research Article
Copyright
Copyright © ICIPE 1981

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References

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