The Ecology of Heliothis Species in Relation to Agroecosystems

restricted geographic distribution (H. punctigera, H. viriplaca) or host range (H. assulta, H. peltigera) than the major pest species. This review is limited to H. armigera, H. zea, H. vires cens, and H. punctigera. The other species, though of local significance, do not consistently achieve damaging pop­ ulations and have only been subject to superficial ecological study (10 , 27, 67, 105, 135 , 179, 192). Other minor pest species occur in the African genus Heliocheilus but are not dealt with here (see 105a). As key pests of several agricultural and horticultural crops, the four species I have singled out for review have attracted an enormous volume of research work. Consequently, the literature on their ecology , biology and management is vast. Rather than attempt a comprehensive review of all facets of the biology and ecology of Heliothis spp. in agricultural systems, I concentrate on