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Relative Effectiveness of Insecticide Sprays on Insect Damage and Yield of Three Cowpea Cultivars in Swaziland

Published online by Cambridge University Press:  19 September 2011

G. W. K. Mensah
G. W. K. Mensah
Affiliation:
Faculty of Agriculture, University of Swaziland, Luyengo Campus, Swaziland
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Abstract

Field trials were carried out for two seasons on the effect of insecticides on insect pests, damage and yield of three cowpea cultivars.

During the first season, the preflowering stage of crop growth was found to be infested by Aphis spp, Empoasca spp, Ootheca spp and Epilachna spp, the flowering stage by Megalurothrips sjostedti, Heliothis armigera, Astylus atromaculatus, Coryna kersteni and Mylabris amplectens and the postflowering stage by H. armigera and a number of coreid and pentatomid bugs. Fenthion gave the least protection against pod damage by H. armigera. There were significant increases in the number of harvestable pods per plant with insecticides. There were no significant differences in hull weight and shelling percentage. Grain yield was increased by 96.2 and 109.4% after treatment with dichlorvos and cypermethrin, respectively.

In the second season, cypermethrin and monocrotophos were most effective. Cypermethrin reduced the number of pod-sucking bugs by 58%, H. armigera by 93%, while monocrotophos reduced Empoasca spp by 39% and M. sjostedti by 79%. Cypermethrin reduced damage by pod-sucking bugs by 28%, and by H. armigera by 95%. Monocrotophos reduced damage by pod-sucking bugs by 14%, and by H. armigera by 80%. Significant increases in the number of harvestable pods per plant were obtained with monocrotophos and cypermethrin treatments. There were no significant differences between the number of seeds per pod, and the weight of 1000 seed-grains. Grain yield was increased by 55.4% after both cypermethrin and monocrotophos treatment. The application of these insecticides were financially beneficial but the gain was reduced when six sprays were applied. Cypermethrin and monocrotophos are promising insecticides for controlling insect pests on cowpeas.

Résumé

Des études aux champs ont été menées pendant deux saisons afin d'évaleur l'efficacité des insecticides contre des insectes, leurs effets nefastes et la recolte sur trois variétés de haricot.

Pendant la première saison, les plantes ont été infestées par Aphis spp, Empoasca spp, Ootheca spp et Epilachna spp avant la fleuraison, par Megalurothrips sjostedti, Heliothis armigera, Astylus atromaculatus, Coryna kersteni et Mylabris amplectens pendant la fleuraison, et par H. armigera et un nombre de bruches du type coreid et Pentatomid après la fleuraison. Fenthion était moins protectrice contre les attaques de H. armigera. L'application des insecticides a donné lieu à des augmentations de nombre de cosses recoltés par plante. On a pas constaté de difference significative en ce qui concerne le poids brut et le pourcentage d'egrenage. La récolte a été considerablement augmentée de 96.2 et 109.4% après traitement avec dichlorvos et cypermethrin respectivement.

Au cours de la deuxième saison, cypermethrin et monocrotophos se sont reveles les plus efficaces.

L'application de cypermethrin a diminué de 58% le nombre des insectes qui attaquent les cosses et de 93% en ce qui concerne H. armigera tandis que la reduction de nombre des insectes par monocrotophos était de 39% pour Empoasca spp et de 79% pour M. sjostedti. Le traitement par cypermethrin a diminué de 28% les attaques par les bruches attaquant les cosses et de 95% par H. armigera. Quant au traitement par monocrotophos la diminution était de 14% pour les bruches attaquant les cosses et de 80% pour H. armigera. Des augmentations significatives de nombre de cosses recoltés par plante ont été obtenu avee monocrotophos et cypermethrin. Aucune difference significative n'a été observée entre le nombre de grains par cosse, soit le poids raméné à 1000 grains. La récolte a été augmenté de 55.4% après traitement avec cypermethrin et séparément avec monocrotophos.

L'application de ces insecticides a été financièrement bénéfique mais le gain a été réduit lorsque six arrosages ont été effectués. Cypermethrin et monocrotophos sont des insecticides de promesse pour le contrôle de pestes qui attaquent les haricots.

Keywords

Field trialscowpea cultivarsinsecticide spraysinsect pestsinsect damageyieldÉtudes aux champsvariétés de haricotsaerosols d'insecticidesinsectes pestesattaques d'insectesrecolte evaluation
Type
Research Articles
Information
International Journal of Tropical Insect Science , Volume 9 , Issue 1 , February 1988 , pp. 101 - 108
Copyright
Copyright © ICIPE 1988

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References

REFERENCES

Agyen-Sampong, M. (1978) Pests of cowpea and their control in Ghana. In Pests of Grain Legumes: Ecology and Control. (Edited by Singh, S. R., Van Emden, H. F. and Taylor, T. A.). Academic Press, London.Google Scholar
Allen, D. J., Anno-Nyako, F. O., Ochieng, R. S. and Ratinam, M. (1981) Beetle transmission of cowpea mottle and southern bean mosaic viruses in West Africa. Trop. Agric. (Trinidad) 58, 171–175Google Scholar
Anonymous (1977) International Institute of Tropical Agriculture 1976 Annual Report. Ibadan, Nigeria.Google Scholar
Anonymous (1982) Intercropping Research (Swaziland). Phase I Technical Report. Faculty of Agriculture, University of Swaziland.Google Scholar
Anonymous (1984) International Institute of Tropical Agriculture 1983 Annual Report. Ibadan, Nigeria.Google Scholar
Bohlen, E. (1973) Crop Pests in Tanzania and their Control. Verlag Paul Parey, Berlin.Google Scholar
Booker, R. H. (1965) Pests of cowpea and their control in Northern Nigeria. Bull. ent. Res. 55, 663–672.CrossRefGoogle Scholar
Dina, S. O. (1977) Effects of monocrotophos on insect damage and yield of cowpea (Vigna unguiculata) in Southern Nigeria. Expl. Agric. 13, 155–159CrossRefGoogle Scholar
Dina, S. O. (1979) Synthetic pyrethroids for the control of cowpea insect pests. J. Agric. Sci., Camb. 93, 735–747.CrossRefGoogle Scholar
Dina, S. O. (1981) Response of three cowpea varieties to organophosphorus insecticides. Trop. Grain Legume Bull. 23, 6–10.Google Scholar
Duncan, D. B. (1955) Multiple range and multiple F tests. Biometrics 11, 1–42.CrossRefGoogle Scholar
Ezueh, M. I. (1981) Nature and significance of preflowering damage by thrips to cowpea. Ent. Exp. Appl. 29, 305–312CrossRefGoogle Scholar
Jackai, L. E. N. and Daoust, R. A. (1986) Insect pests of cowpeas. A. Rev. Ent. 31, 95–119.CrossRefGoogle Scholar
Koehler, C. S. and Mehta, P. N. (1972) Relationships of insect control attempts by chemicals to components of yield of cowpeas in Uganda. J. Econ. Ent. 65, 1421–1427.CrossRefGoogle ScholarPubMed
Matteson, P. C. (1982) Effects of intercropping with cereals and minimum permethrin applications on insect pests of cowpea and their natural enemies in Nigeria. Trop. Pest Manage. 28, 372–380.CrossRefGoogle Scholar
Okeyo-Owuor, J. B., Agwardo, P. O. and Simbi, C. O. J. (1983) Studies on legume pod-borer, Maruca testulalis (Geyer)—V. Larval population. Insect Sci. Applic. 4, 75–81.Google Scholar
Price, M., Chambuya, R. I. and Machange, F. Z. (1983) Insecticide evaluation and timing of spray application for insect control in cowpeas in Tanzania. Trop. Grain Legume Bull. 28, 4–8.Google Scholar
Raman, K. V., Singh, S. R. and Van Emden, H. F. (1980) Mechanism of resistance to leafhopper damage in cowpea. J. econ. Ent. 73, 484–488.CrossRefGoogle Scholar
Singh, S. R. and Taylor, T. A. (1978) Pests of grain legumes and their control in Nigeria. In Pests of Grain Legumes: Ecology and Control (Edited by Singh, S. R., Van Emden, H. F. and Taylor, T. A.). Academic Press, London.Google Scholar
Singh, S. R., van Emden, H. F. and Taylor, T. A. (Eds) (1978) Pests of Grain Legumes: Ecology and Control. Academic Press, London.Google Scholar
Ta'Ama, M. (1983) Yield performance of thrips resistant cultivars on insecticide application. Trop. Grain Legume Bull. 27, 26–28.Google Scholar
Taylor, T. A. (1968) The effects of insecticide applications on insect damage and the performance of cowpea in Southern Nigeria. Niger. Agric. J. 5, 29–37Google Scholar
Taylor, T. A. (1977) Studies in the Development of African Resources 4: Crop Pests and Diseases. Oxford University Press, Ibadan, Nigeria.Google Scholar
Taylor, T. A. (1978) Maruca testulalis: An important pest of tropical grain legumes. In Pests of Grain Legumes: Ecology and Control (Edited by Singh, S. R., van Emden, H. F. and Taylor, T. A.). Academic Press, London.Google Scholar