The Role of Sorghum Legume Intercroping System in Improving Soil Productivity on Small Holder Farmers in Western Kenya

Declining crops yield in the smallholder farmers cropping systems of sub-Saharan African (SSA) present the need to develop more sustainable production systems. Depletion of essential plant nutrients from the soils have been cited as the main contributing factors due to continues cultivation of cereal crops without application of organic/ inorganic fertilizers. Field experiments to evaluate effect of phosphorus (P) fertilizers, organic and integration of legumes in sorghum cropping systems on soil, available nitrogen (N) and P, were conducted in Busia County of Kenya during the short (SRS) and long rain seasons (LRS) of 2016 and LRS of 2017 respectively. The experiments comprised either soybean, common bean groundnut or sesame grown with sorghum. The design was a split plot in a randomized complete block design. Main plots were fertilizer inputs; Mavuno, FYM or their combination. Subplots comprised of the legume intercrops mentioned above. Application of Mavuno, FYM or their combination resulted in significantly higher legume, sesame crop yields above the control in the second season. Legume crops due to their N-fixation, litter fall and mineralization made availability of P and N. possible. Application of Mavuno, FYM or their combination gave comparable results with respect to the intercrop yields. Since FYM and (Mavuno+FYM) is cheaper than Mavuno, growing either soybean, common bean groundnut or sesame intercropping system with sorghum with application of the above is recommended for improved legume grain yields and soil fertility improvement.