Review articleBiology, ecology and management of cereal stemborers in Africa, with particular reference to Ethiopia

Abstract

Grains of gramineous crops are of paramount importance in the world for feeding humans and livestock, and generating income. Moreover, the stalks of thick stemmed gramineous crops such as maize and sorghum are used for fuel, construction and livestock feed. The contribution of cereals like maize and sorghum towards food requirements of Ethiopian population is tremendous and these cereals rank first and second, respectively, in terms of yield per hectare and total production. However, their yields are affected by a large number of lepidopteran stemborers found in the families Pyralidae, Crambidae and Noctuidae and two species of Coleoptera in the family of Rhynchophoridae. Of the stemborer species attacking cereals, the spotted stemborer, Chilo partellus (Swinhoe) is an exotic species which has no co-evolved natural enemies to keep its population low. This species is very problematic in the dry lowland of eastern and southern African countries including Ethiopia. The other problematic species which is indigenous to Africa is maize stemborer, Busseola fusca (Fuller). This species can cause complete crop failure in most African countries in the wet-higher elevation. Other than these two species, the stemborers recorded in Africa are either minor or sporadic or pests of pocket areas. The yield losses due to these stemborers to cereals have been reported to vary from country to country and ranges from 20-80% depending on the pest density, type and variety of crops, species of stemborers involved in the infestation and phenological stage of the crop during infestation. To combat the complex species of stemborers involved in the infestation of important cereal crops, quite a large number of basic and applied researches have been conducted in Africa which include species composition, economic importance, distribution, biology, ecology and management. Hence, in this paper, critical review of stemborers’ research outputs is presented. From the review, conclusions and recommendations are made to help cereal growers to make use of research results for the effective management of cereal stemborers which ultimately boost production and productivity. Keywords/phrases: Applied research; Basic research; Cereal stemborers; Cereal stemborers management; ReviewEthiop. J. Biol. Sci., 9(1): 79-116, 2010