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Seasonal population fluctuations in the black cowpea moth Cydia ptychora (Meyrick) (Lepidoptera:Tortricidae)

Published online by Cambridge University Press:  19 September 2011

J. I. Olaifa
Affiliation:
Department of Plant Science, University of Ife, Ile-Ife, Nigeria
A. E. Akingbohungbe
Affiliation:
Department of Plant Science, University of Ife, Ile-Ife, Nigeria
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Abstract

Investigations were carried out on the seasonal population fluctuations of the moth Cydia ptychora. The population increased from May to September and declined from November to April. Increasing temperatures and decreasing r.h. appeared to be associated with population decline, while the reverse seemed to favour population increase.

From light trap catches, sex ratios of adults showed considerable variation from month to month. The overall ratio was 2:1, in favour of the males, but there was a tendency for adjustment towards an apparently female-biased ratio from March to August.

Bracon (?) hancocki was found to be a major parasite. Other biotic factors contributing to population regulation included 13 hymenopterous parasites and three predators (Philodicus temerarius, Bactria sp. nr. guineensis and Chrysopa sp.)

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Articles
Copyright
Copyright © ICIPE 1982

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References

REFERENCES

Ayoade, K. A. (1975) Preliminary investigations into effects of some insecticides, sprayers and methods of application on the insect pests and yields of cowpea (Vigna ungukulata (L.) Walp. Niger. J. Ent. 1, 133141.Google Scholar
Dina, S. O. (1977a) Effects of monocrotophos on insect damage and yield of cowpea Vigna unguiculata in Southern Nigeria. Expl Agric. 13, 155159.CrossRefGoogle Scholar
Dina, S. O. (1977b) Effects of rates of monocrotophos application on insect damage, grain yield and economy of field cowpea. Niger, agric. J. 13, 4449.Google Scholar
Dina, S. O. (1979) Synthetic pyrethroids for the control of cowpea insect pests. J. agric. Sci. 93, 735749.CrossRefGoogle Scholar
Ezhdinma, F. O. C. (1966) Some observations on the effect of time of planting on cowpea Vigna unguiculata (L.) Walp. in Southern Nigeria. Trop. Agric, Trin. 43, 8387.Google Scholar
Huffaker, C. B., Messenger, P. S. and De Bach, P. (1972) The natural enemy component in natural control and the theory of biological control. In Biological Control (Edited by Huffaker, C. B.), pp. 1667. Plenum Press, New York.Google Scholar
Nangju, D., Nwanze, K. F. and Singh, S. R. (1979) Planting date, insect damage and yield of cowpea in Western Nigeria. Expl Agric. 15, 289298.CrossRefGoogle Scholar
Olaifa, J. I. (1979) Studies on the biology and dynamics of the black cowpea moth Cydia ptychora (Meyrick) (Lepidoptera:01ethreutidae) at Ile-Ife. M. Phil, thesis, University of Ife, Nigeria.Google Scholar
Olaifa, J. L. and Akingbohungbe, A. E. (1981) Aspects of the biology of the black cowpea moth Cydia ptychora (Lepidoptera:Tortricidae) related to host plant phenology. Ann. appl. Biol. 97, 129134.CrossRefGoogle Scholar
Perrin, R. M. (1977) Studies on host-plant selection by the cowpea seed moth Cydia ptychora. Ann. appl. Biol. 87, 175182.CrossRefGoogle Scholar
Perrin, R. M. (1978a) The effect of some cowpea varieties on the development and survival of larvae of the seed moth Cydia ptychora Meyrick (Lepidoptera:Tortricidae). Bull. ent. Res. 68, 5763.CrossRefGoogle Scholar
Perrin, R. M. (1978b) Varietal differences in the susceptibility of cowpea to larvae of the seed moth Cydia ptychora Meyrick (Lepidoptera:Tortricidae). Bull. ent. Res. 68, 4756.CrossRefGoogle Scholar
Singh, S. R. and Van Emden, H. F. (1979) Insect pests of grain legumes. A. Rev. Ent. 24, 255278.CrossRefGoogle Scholar
Smith, D. A. S. (1975) All female broods in the polymorphic butterfly Danaus chrysippus L. and their ecological significance. Heredity 34, 363371.CrossRefGoogle ScholarPubMed
Taylor, T. A. (1965) Observations on the bionomics of Laspeyresia ptychora Meyrick (Lepidoptera:Eucosmidae) infesting cowpea in Nigeria. Bull. ent. Res. 55, 761773.CrossRefGoogle Scholar