Management Approaches:
Host Plants

Maize

Cultivated maize (Zea mays) as we know it today originated in Central America, probably within the area equivalent to modern Mexico.  When Columbus arrived in America at the end of the 15th century, maize was already an important food crop among the South Americans from Mexico to Peru.  By the 16th century, maize was already being cultivated in southern Europe, parts of West and southern Africa, and Asia.  By the 17th century, maize was present in virtually all areas of Africa in which it could be cultivated.  Despite the existance of African maize for over 300 years, it must still be considered a relatively recent introduction in comparison with the more traditional african cereals, such as millet and sorghum, in terms of both agroecology and insect-plant coevolution.  In Africa, maize is used as both human and animal food, eaten directly as grilled cobs or as various products of maize flour.  It is easily stored afer drying and/or milling.

In general, maize in Africa is grown by small-scale farmers for local consumption, and yields tend to be very low, averaging less than half of Asian and Latin American yields (FAO, 1993).  In recent years, however, there have been attemps to cultivate more extensive maize monocultures with the aid of irrigation, for example in northern Senegal.  On small farms, maize is very often intercropped with legumes, such as groundnuts, cowpeas or haricot beans.  Principle producers of maize in sub-Saharan Africa are Kenya, South Africa and Tanzania, followed by Ethiopia and Nigeria, although South Africa is the only one of these exporting maize in any quantity.

The stem-borer species most often associated with maize are the noctuids Busseola fusca and various Sesamia species, particularly S. calamistis and S. cretica.  Throughout Africa, B. fusca is known as the maize stalk borer.  Important crambid and pyralid borers of maize in Africa are Eldana saccharina (Pyralidae) and several Chilo species (Crambidae).  Chilo partellus, a species introduced accidentally from Asia earlier this century is one of the major pests of maize in East and Southern Africa.  At the time of writing, it has not yet become a pest in west Africa.  Other Chilo species that can be pests include C. aleniellus and C. diffusilineus in West africa and C. orichalcociliellus in East Africa and Madagascar.  Coniesta ignefusalis, the principle borer of millet, also attacks maize in some parts of West Africa.

Major references: Acland (1971); Harrison (1981); Rouanet (1984); Ibekwe (1986).