Legume based intercropping and its effect on selected soil macrofaunal populations and maize yield

Abstract

In Uganda just like other tropical areas, natural fallows, which were traditionally used in order to improve soil fertility, are no longer possible due to high population pressure. Many studies have underlined the advantages of legume cover crops to ensure the sustainability of plant productivity. However, the relationship between maize intercrops and macro faunal abundance and their effect on maize yield are not completely understood. The characterisation of biological diversity in in different agricultural ecosystems can help in understanding the dynamics of soil quality and the changes in soil nutrients. For this purpose, the number, abundance, weight and biomass of earthworms, termites, centipeds and millipedes were determined under different maize-legume intercrops. The four treatments were: (1) maize bean intercrop (MB); (2) a maize soya bean intercrop (MS); and (3) a maize in pill push intercrop with Desmodium intortum and Braceria molato (PP) and a control of maize in monocrop (MM). The macro faunal population in the MB plots was higher than in other plots for earthworms, millipedes and centipedes. However, the MM plots had a significantly high termite abundance compared to the intercropped maize plots (p<0.05). Maize yield was highest in the MS plots and linear regression analysis for the relationship of yield and earthworm abundance was positively significant (p<0.05). Understanding of the modifications in biodiversity in maize land use are necessary for sustainable management of management of agro ecosystems.