Evaluation of Bt.-Transgenic maize for resistance to the stem borers Busseola fusca (Fuller) and Chilo partellus (Swinhoe) in South Africa

Abstract

The gene Cry1Ab derived from the entomopathogenic bacterium Bacillus thuringiensis is currently deployed commercially for control of Pyralid stem borers of maize in the USA. In this study various events of the Bt-gene were evaluated in maize inbred lines and hybrids for leaf feeding resistance to the local stem borers Busseola fusca and Chilo partellus, using artificially infested plants under greenhouse and field conditions. The event MON810 proved superior to all other events tested. C. partellus was more susceptible than B. fusca to the same events. Significant maternal effects were observed. Efficacy was not negatively affected by variations in the time of infestation. Hybrids did not respond equally to transformation with the same event, which was attributed to differences in adaptation to adverse environmental conditions.