Biology and Management of Economically Important Lepidopteran Cereal Stem Borers in Africa

Abstract

▪ Abstract Cereals (maize, sorghum, millet, rice) are extremely important crops grown in Africa for human consumption. Of the various insect pests attacking cereal crops in Africa, lepidopteran stem borers are by far the most injurious. All 21 economically important stem borers of cultivated grasses in Africa are indigenous except Chilo partellus, which invaded the continent from India, and C. sacchariphagus, which has recently been found in sugarcane in Mozambique. C. partellus is competitively displacing indigenous stem borers in East and southern Africa. A parasitoid, Cotesia flavipes, was introduced from Pakistan for biological control of C. partellus and caused a 32–55% decrease in stem borer densities. This article is an attempt to summarize the status of knowledge about economically important cereal stem borers in Africa with emphasis on their distribution, pest status and yield losses, diapause, natural enemies, cultural control, host plant resistance, and biological control. Special attention is given to Busseola fusca and C. partellus, the most important pests of maize and grain sorghum.

Phylogeographic pattern and regional evolutionary history of the maize stalk borerBusseola fusca(Fuller) (Lepidoptera: Noctuidae) in sub-Saharan Africa

“…Th e fact that B. fusca, considered as oligophagous (Le now preferentially uses maize and cultivated sorghum in most part of its distribution areas suggests that these host plants off er this species very suitable resources. Th e preference for these cultivated plants (Kfi r et al 2002 would represent one of the factors that might have led B. fusca to start ecological specialization between populations. Th is ecological segregation between B. fusca populations exploiting wild and cultivated host plants or cultivated sorghum and maize could be highlighted by further molecular studies.…”

“…Busseola fusca varies in its ecological preference across its geographical range. It is more adapted to lowland in West Africa than in East and Southern Africa (Kfi r et al 2002). Previous study on the genetic structure of B. fusca shows that this ecological preference is associated with major diff erences in partial DNA sequence of the cytochrome b mitochondrial gene (Sezonlin et al 2006).…”

“…Most of these cereal crops serve as host plants for many stem borer insects among which Busseola fusca (Fuller 1901) (Lepidoptera: Noctuidae) is one of the most economically important pests (Polaszek & Khan 1998). B. fusca is an endemic species in subSaharan Africa with wide geographical distribution (Ajayi 1998;Moyal 1998;Ndemah et al 2001;Haile & Hofsvang 2001;Kfi r et al 2002). It is a major pest of sorghum (Sorghum bicolor [L.] Moench) and maize (Zea mays L.) (Poaceae).…”

Temporal patterns of emergence, calling behaviour and oviposition period of the maize stem borer,Busseola fusca(Fuller) (Lepidoptera: Noctuidae)

“…Paul-André Calatayud (1) , Hervé Guénégo (2) B usseola fusca (Fuller) (Lepidoptera: Noctuidae) is a serious pest of maize and grain sorghum in subSaharan Africa (Kfi r et al 2002). Th is insect species is mostly found on cultivated habitat and rarely on wild grasses (Le Ong'amo et al, 2006a;Ong'amo et al, 2006b;Otieno et al, 2006, Wale et al, 2006.…”

Genetic hitchhiking and resistance evolution to transgenic Bt toxins: insights from the African stalk borer Busseola fusca (Noctuidae)

“…Although this pest species is seldom hosted by wild grasses (Le , it is responsible for substantial yield losses in maize, sorghum (Kfir et al, 2002) and more marginally sugarcane crops (Assefa et al, 2015). Being endemic to Sub-Saharan Africa and widely distributed throughout the region (Dupas et al, 2014), B. fusca is considered a pest of economic importance.…”