Skip to main content Accessibility help

Products derived from the leaves of Ocimum kilimandscharicum (Labiatae) as post-harvest grain protectants against the infestation of three major stored product insect pests

  • B. Jembere (a1), D. Obeng-Ofori (a1), A. Hassanali (a1) and G.N.N Nyamasyo (a2)


The bioactivity of materials from the leaves of Ocimum kilimandscharicum was tested against Sitophilus zeamais Mots chulsky (Coleoptera: Curculionidae), Rhyzopertha dominica (Fabricius) (Coleoptera: Bostrichidae) and Sitotroga cerealella (Olivier) (Lepidoptera: Gelechiidae) in maize and sorghum grains in the laboratory. Exposure of adults of the three insect species to dried ground leaves and essential oil extract of O. kilimandscharicum induced 100% mortality after 48 h. Fresh and dried whole leaves were not toxic to Sitophilus zeamais or R. dominica. Grains treated with dried ground leaves and essential oil extract caused significant reductions in the number of progeny and survival rate of all three pest species tested. There was no adult survival or progeny production in grains treated separately with each of the two materials at doses of 25.0 g (dried ground leaves) and 0.3 g (essential oil) per 250 g of grain, respectively. Unlike R. dominica and Sitotroga cerealella, grains treated with fresh leaves enhanced the feeding activity of Sitophilus zeamais. Ground leaves and the essential oil, however, protected the grains against feeding by all three species, resulting in lower weight loss and number of damaged seeds compared with untreated grains. All the plant materials were repellent to S. zeamais with the essential oil extract applied at 0.3 g/250 g of grain evoking the highest repellent action. There was, however, considerable variation in the repellency of the materials against R. dominica and Sitotroga cerealella. The results are discussed in terms of the efficacy of O. kilimandscharicum for protection against loss due to insects in traditional grain storage in developing countries.


Corresponding author

Dr A. Hassanali, ICIPE, P.O. Box: 30772, Nairobi, Kenya.


Hide All
Abbott, W.S. (1925) A method of computing the effectiveness of an insecticide. Journal of Economic Entomology 18, 265267.
Casida, J.H. (1990) Pesticide mode of action: evidence for and implications of a finite number of biochemical targets. pp. 1122in Casida, J.E. (Ed.) Pesticides and alternatives: innovative chemical and biological approaches to pest control. Amsterdam, Elsevier.
Charles, D.J. & Simon, J.E. (1990) Comparison of extraction methods for the rapid determination of essential oil content and composition of basil. Journal of the American Society of Horticulture 115, 458462.
Ezueh, M.I. (1983) Control of stored product pests. pp. 250263in Youdeowei, A. & Service, M.W. (Eds) Pest and vector management in the tropics. London and New York, Longman.
Fao, (1985) Prevention of post harvest food losses. Training series no. 10. 122 pp. Rome, Food and Agriculture Organization of the United Nations.
Guenter, E. (1949) The essential oils. Vol. iii. 399 pp. Toronto, Van Nostrand.
Hassanali, A., Lwande, W., Ole-Sitayo, N., Moreka, L., Nokoe, S. & Chapya, A. (1990) Weevil repellent constituents of Ocimum suave leaves and Eugenia caryophyllata cloves used as grain protectant in parts of eastern Africa. Discovery and Innovations 2, 9195.
Howe, R.W. (1965) Losses caused by insects and mites in stored foods and foodstuffs. Nutrition Abstracts and Review 35, 285302.
Kokwaro, J.O. (1976) Medicinal plants of East Africa. 384 pp. Nairobi, East African Literature Bureau, General printers Limited.
Regnaul-oger, C., Hamraoul, A., Holeman, M., Theron, E. & Pinel, R. (1993) Insecticidal effects of essential oils from Mediterranean plants upon Acanthoscelides obtectus (Say) (Coleoptera: Bruchidae), a pest of kidney bean (Phaseolus vulgaris (L.)). Journal of Chemical Ecology 19, 12331244.
Santhoy, G. & Rejesus, B.M. (1975) The development rate, body weight and reproduction capacity of Sitophilus zeamais Motsch. reared on three natural hosts. Physiological Entomology 2, 311321.
Saxena, R.C., Jilani, G. & Kareem, A.A. (1988) Effect of neem on stored grain insects.pp. 98111in Jacobson, M. (Ed.) Focus on phytochemical pesticides. Boca Raton, Florida, CRC Press.
Weaver, D.K., Dunkel, F.V., Ntezurubranza, L., Jackson, L.L. & Stock, D.T. (1991) The efficacy of linalool, a major component of freshly-milled Ocimum canum (Sims) (Lamiaceae), for protection against postharvest damage by certain stored product Coleoptera. Journal of Stored Product Research 27, 213220.

Related content

Powered by UNSILO

Products derived from the leaves of Ocimum kilimandscharicum (Labiatae) as post-harvest grain protectants against the infestation of three major stored product insect pests

  • B. Jembere (a1), D. Obeng-Ofori (a1), A. Hassanali (a1) and G.N.N Nyamasyo (a2)


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.