Hostname: page-component-848d4c4894-m9kch Total loading time: 0 Render date: 2024-05-28T23:35:50.605Z Has data issue: false hasContentIssue false

Insecticide Studies on East African Agricultural Pests. I.—Epilachna hirta (Thnb.). II.—Cylas puncticollis Boh

Published online by Cambridge University Press:  10 July 2009

P. T. Walker
Affiliation:
Colonial Pesticide Research Unit, Arusha, Tanganyika.

Summary

Results are given of laboratory trials of insecticides, carried out in Kenya, against two pests of agricultural crops in East Africa. Against Epilachna hirta (Thnb.) (Col., COCCINELLIDAE), the adults and larvae of which feed on the foliage of wheat and other crops, dusts containing 0·5 or 2 per cent, parathion, applied at rates to give 0·74 to 2·97 mg. active ingredient per sq. ft., were the most rapidly effective against the adults. A 5 per cent. DDT dust, at rates giving 0·36 to 5·82 mg. technical DDT per sq. ft., was less rapid in action but produced very good results by the end of three days. A proprietary BHC dust, used at rates giving deposits of from 0·23 to 1·04 mg. γ isomer per sq. ft., was less effective and, at the highest rate used, only reached 100 per cent, mortality after eight days.

Several insecticides were tested in emulsified solutions against Cylas puncticollis Boh. (Col., CURCULIONIDAE), one of the important sweet-potato weevils of East Africa. All the insecticides were applied at concentrations of 0·02, 0·1 and 0·5 per cent, active ingredient, and at a deposit rate of 0·813 mg. of spray per sq. cm. DDT was the most effective after 18 hours, but γ BHC was only slightly inferior.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 1957

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Brannon, L. W. (1949). Tests of some new insecticides to control Mexican Bean Beetle.—J. econ. Ent, 42, pp. 928930.CrossRefGoogle Scholar
Fjelddalen, J. (1950). E.605-parathion.—Gartneryrket, 1950, no. 30, repr. [3] pp. (Rev. appl. Ent., (A) 40, p. 193.)Google Scholar
Ginsburg, J. M., Filmer, R. S. & Reed, J. P. (1952). Recovery of organic insecticides from sprayed and dusted crops.—J. econ. Ent, 45, pp. 428431.CrossRefGoogle Scholar
Graham, J. F. (1953). Annual report of the Senior Entomologist, 1951.—Rep. Dep. Agric. Kenya, 1951, 2, pp. 111.Google Scholar
Huckett, H. C. (1948). Control of the Two-spotted Spider Mite on lima beans, on Long Island.—J. econ. Ent, 41, pp. 202206.CrossRefGoogle Scholar
Le Pelley, R. (1952 a). Note on damage to grazing by grasshoppers in Kenya. —Bull. ent. Res, 43, pp. 7981.CrossRefGoogle Scholar
Le Pelley, R. (1952 b). Annual report of the Senior Entomologist for 1950.— Rep. Dep. Agric. Kenya, 1950, 2, pp. 6071.Google Scholar
Norton, L. B. & Dewey, J. E. [1950]. Synthetic materials as insecticides.— 62nd Rep. Cornell agric. Exp. Sta, 1948–49, pp. 144145.Google Scholar
O'Kane, W. C. (1947). Results with benzene hexachloride.—J. econ. Ent, 40, pp. 133134.CrossRefGoogle ScholarPubMed
Potter, C. (1952). An improved laboratory apparatus for applying direct sprays and surface films….—Ann. appl. Biol, 39, pp. 128.CrossRefGoogle Scholar
Risbec, J. (1947). Les charancons nuisibles aux patates douces.—Agron. trop., Nogent, 2, pp. 375398.Google Scholar
Sherman, M. (1951). Chemical control of sweetpotato insects in Hawaii.—J. econ. Ent, 44, pp. 652656.CrossRefGoogle Scholar
Sherman, M. & Mitchell, W. C. (1953). Control of Sweetpotato Weevils and Vine Borer in Hawaii.—J. econ. Ent, 46, pp. 389393.CrossRefGoogle Scholar
Tothill, J. D. Ed. (1940). Agriculture in Uganda.—551 pp. Oxford, Univ. Press.Google Scholar