Joyce Addah Omwakwe

Maize is the staple food for most Kenyan households, however over the decade maize yields have decreased or remained stagnant. This is partly attributed to poor soil fertility and soil heterogeneity, despite much work having been done to tackle soil fertility issues. To investigate this, 23 soil samples (0 to 30 cm) were collected from 13 counties in Kenya and a nutrient omission trial was set up in the greenhouse at the Kenya Agricultural and Livestock Research Organization (KALRO) Kabete. The objective was to assess soil limiting nutrients and evaluate the response of maize to applied nutrients. The experiment was laid out in a completely randomized design with factorial arrangement. There were 12 treatments; complete (all macro and micro nutrients), complete plus lime, five treatments where one macro nutrient was omitted from the nutrient solution, one treatment where the micro-nutrient mixture was omitted from the nutrient solution, one treatment with all the micro nutrients except zinc, the other with all micronutrients except boron, one treatment with all the micro nutrients except molybdenum and one control (distilled water only). Significantly (P≤0.05) lower dry shoot weights than the complete treatment was observed in most of the soils. The results showed that poor maize growth was mainly due to the omission of nitrogen, phosphorous and zinc. An addition of nutrients, improved the yield in most of the soils. The ability to rapidly assess the nutrientsupplying capacity ofsoilsis an essential first step in developing useful nutrient management systems.