Skip to main content Accessibility help
×
Home

Studies on the legume pod-borer Maruca testulalis (Geyer)—V. Larval population

  • J. B. Okeyo-Owuor (a1), P. O. Agwaro (a1) and C. O. J. Simbi (a1)

Abstract

The studies show that the population of Maruca testulalis fluctuates greatly between the long and short rainy season and is significantly lower during the short and dry season, even when the cowpea crop is maintained under irrigation conditions. Studies on larval and pupal populations at Mbita Point, in Western Kenya and related farmers' plots showed lower populations under pure cowpea than under cowpea-maize intercrop, especially at 50% cowpea flowering stage (i.e. the second sampling stage). Although this difference was consistently manifested in the three seasons of experimentation there was no significant difference in larval population and extent of flower damage. Studies using three susceptible cowpea varieties (Ex-Lwanda, TVX 66-2H, and TVX 1193-059D) showed no significant difference in larval, pupal and adult populations when unsprayed. However, when sprayed with dimethoate (Rogor E 40) a systemic insecticide, significantly higher larval population was obtained in TVX 1193-059D, which shows the most vegetative growth of the three varieties. The borer damage on the flowers was not significantly different in all varieties under both the sprayed and unsprayed conditions. Studies using assessment of the different larval instars of M. testulalis in both sprayed and unsprayed conditions showed a continuous infestation of the crop throughout the season unless pod and flower production ceased. The fourth and fifth instar larvae were more abundant in pods than in flowers of the cowpea plant.

Copyright

References

Hide All
Booker, R. H. (1963) Notes on the pest complex of cowpea in Northern Nigeria. Proc. 1st Nigerian Grain Legume Conference, Institute of Agricultural Research, Samaru, Zaria, Nigeria, pp. 912.
Booker, R. H. (1965) Pests of cowpea and their control in Northern Nigeria. Bull. ent. Res. 55, 663672.
Jerath, M. L. (1968) Insecticidal control of Maruca testulalis on cowpea in Nigeria. J. econ. Ent. 66, 423–416.
Koehler, C. S. and Mehta, P. N. (1972) Relationships of insect control attempts by chemicals to components of yield on cowpea in Uganda. J. econ. Ent. 65, 14211427.
Okeyo-Owuor, J. B. and Ochieng', R. S. (1981) Studies on the legume pod-borer, Maruca testulalis (Geyer)—I. Life cycle and behaviour. Insect Sci. Application 1, 263268.
Raheja, A. J. (1974) Report on the insect pest complex of grain legumes in Northern Nigeria. Proc. 1st IITA Grain Legume Improvement Workship (1973), Int. Inst. Trop. Agric, Ibadan, Nigeria, pp. 295299.
Taylor, T. A. (1964) The field pest problems on cowpea, Vigna sinensis L. in southern Nigeria. Nig. Grower Producer 3, 14.
Taylor, T. A. (1968a) The effect of insecticide application on insect damage and the performance of cowpea in southern Nigeria. Niger. Agric. J. 5, 2937.
Taylor, T. A. (1978) Maruca testulalis; an important pest of tropical grain legumes. In Pest of Grain Legumes: Ecology and Control. (Edited by Singh, S. R., Van Emden, H. F. and Taylor, T. A.), pp. 193202. Academic Press, London, New York.

Keywords

Studies on the legume pod-borer Maruca testulalis (Geyer)—V. Larval population

  • J. B. Okeyo-Owuor (a1), P. O. Agwaro (a1) and C. O. J. Simbi (a1)

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed.