Maize–legume intercropping and push–pull for management of fall armyworm, stemborers, and striga in Uganda

Abstract

Maize (Zea mays L.) production in Africa is constrained by several biotic and abiotic factors. The recent occurrence of fall armyworm (FAW), Spodoptera frugiperda (JE Smith) a new invasive pest in Africa, has escalated the problem. Push–pull technology (PPT), proven to be effective for stemborers (Chilo partellus Swinhoe and Busseola fusca Fuller) and the parasitic weed striga (Striga hermontica Delile) management in Africa has been shown to provide good control of FAW. This study investigated if intercropping maize with edible legumes can also reduce the abundance of FAW. Six treatments including (i) climate-smart PPT, (ii) conventional PPT, (iii) maize intercropped with bean (Phaseolus vulgaris L.), (iv) maize intercropped with soybean [Glycine max (L.) Merr.], (v) maize intercropped with groundnut [Vigna unguiculata (L.) Walp.] and, (vi) mono-cropped maize were evaluated on farm in six districts of Uganda in the 2017 short rains season. Data collected included FAW, stemborer, and striga infestation symptoms, and severity of infestation. Climate-smart PPT performed best in reducing stemborer, FAW, and striga infestation followed by conventional PPT over all the phenological stages of maize. Intercropping of maize with leguminous crops also provided significant reduction of stemborer and FAW compared to mono-cropped maize, especially in the early growth phases of the maize up to tasseling. However, intercropping of maize with edible legumes was not very effective for striga management as compared to PPT. Hence in addition to PPT, intercropping of maize with edible legumes could also be an alternative FAW management option when integrated with other sustainable management measures.