Integrating Inorganic and Organic Fertilizers in Cropping Systems for the Transformation of Maize Productivity in Nakuru County

Abstract

Despite the immense significance of maize (Zea mays L.) for Kenya’s economic prosperity and food security, productivity and production have not significantly increased over time. This is attributed to a number of things, including decreased soil fertility. In order to ascertain the applicability of Integrated Soil Fertility Management (ISFM), a study was carried out between 2016 and 2017 in Nakuru County at the Kenya Agricultural and Livestock Research Organization (KALRO), Njoro Centre, Nakuru County. The treatments were arranged in a split-split plot in a randomized complete block design (RCBD) replicated four times. Soil and water conservation (SWC) and conventional tillage (CT) were allocated to the main plot, the split-plots and fertilizer sources i.e Farm yard manure (FYM), Nitrogen (N) and Phosphoros (P) fertilizers to the split-split plot. Kenya Seed Company maize hybrid (H6213) and Egerton bean variety (Chelalang) were used as test crops. A variety of maize and bean (Phaseolus vulgaris L) characteristics, such as plant stand at germination, plant vigor, days to 50% blooming, days to 50% maturity, plant stand at harvest, number of pods per plant, number of cobs, number of seeds per pod, grain yield, and 100-grain weight, were all recorded. Applying a full rate of inorganic fertilizer resulted in significantly maize yields (P< 0.05) compared to all other fertility management strategies, with the exception of those where a half rate of both inorganic and organic fertilizers was applied. The results further showed that the use of inorganic fertilizer alone considerably increased maize output whether cultivated as a sole crop or an intercrop compared to farmyard manure applied alone or in conjunction with inorganic fertilizer. The application of inorganic fertilizer either alone or in conjunction with farmyard manure significantly (P< 0.05) increased the grain production of maize, which suggested that maize would benefit from ISFM options. The results generally indicated that maize was a good competitor in an intercropping system of beans and maize, which reduced the output of beans.