FERTILITY STATUS OF EUTRIC NITISOL AND FERTILIZER RECOMMENDATION USING NUMASS IN THE SELECTED AREAS OF JIMMA ZONE, SOUTHWESTERN ETHIOPIA

Abstract

Nutrient management decision support system (NuMaSS) is a tool that diagnoses soil constraints and selects the appropriate management practices, based on agronomic, economic and environmental criteria, for location-specific conditions. However, its validation in different soil orders and agroecosystems should be tested. Thus, the present study was conducted to assess the fertility status of Eutric Nitisol and suggests the application of NuMaSS as a diagnostic tool to recommend supplementary N and P fertilizers for maize across different agroecology zones. Accordingly, fifty soil samples were collected from five locations and analyzed for the major soil physical and chemical properties. The soil pH-H2O was below the critical level for all soil samples. Nitrogen, Cu and Zn were deficit in all soil samples. Deficiency of available phosphorous was also observed in 88% of the soil samples. High probabilities of nitrogen and phosphorous deficiency were also observed in the study areas using NuMaSS. Moreover, 24 kg/ha P and 73 kg/ha N for Dedo; 24kg/ha P and 82 kg/ha N for Agaro; 20 kg/ha P and 100 kg/ha N for Serbo; 27 kg/ha P and 94 kg/ha N for Dimtu; and 4.9kg/ha P and 97 kg/ha N for Asendabo were recommended for maize using NuMaSS.