Survival of maize stalk borer, Busseola fusca (Fuller), in crop residues in Ethiopia

Abstract

The importance of maize crop residues, stalks and stubble after harvest as sources of maize stalk borer, Busseola fusca (Fuller) survival during the dry season was assessed in 1984 and 1985 on 50 peasant farms in Awassa (Ethiopia). Residues of various length were examined and the presence of diapause larvae was confirmed in all sizes, but significantly more larvae were in longer stalks. Placing infested maize stalks horizontally for 4 weeks, or sorghum stalks horizontally for 2 weeks, was effective in reducing carry-over populations of B. fusca, so the recommended practice of spreading stalks in the field throughout the dry season or burning them completely to kill diapause larvae would not be necessary in Awassa. In contrast, stalks stored upright in stacks immediately after harvest contained the highest number of live larvae during the dry season and proved to be the major source of carry-over populations.