Farmer Field Schools and Integrated Nutrient Management in Semi-Arid Areas of Eastern Kenya: Learning Experiences on Testing of Farmyard Manure, DAP, Tithonia and Their Combinations in the Central Learning Plot, 2003

Abstract

Determinants of crop productivity growth include soil fertility, pests and diseases, weeds and water availability. In the semi-arid areas of Eastern Kenya, the biophysical challenges such as inherent infertile soils, declining soil fertility, and poor rainfall distribution together with farmer's poor socio-economic situation are some of the major factors contributing to declining food production (Onduru et al., 1999). Soils in the semiarid areas generally have low organic matter and total nitrogen contents because of low biomass production and a high rate of decomposition (Mokwunye et al., 1996). Also in many places of the semi-arid areas, nitrogen and phosphorus are limiting. The soils also have low-activity clay, and thus low capacity to fix added phosphorus. This implies that the phosphorus requirement for obtaining maximum yields is often low (Bationo and Mokwunyu, 1991; Osiname, 1979).