Influence of Soil Fertility Management on Nitrogen Mineralization, Urease Activity and Maize Yield

For studying the effect of soil fertility management practices on N mineralization, urease activity and maize yield, replicated field trials were established in 2015 at Misamfu Msekera agricultural research stations (ARS) representing two geo-climatic regions Zambia. The ARS is a sandy clay loam (SCL) from Paleustult, while that loamy sand (LS) Kandiustult. had three categories treatments namely legumes, traditional conventional. legumes group consisted researcher-recommended legume-cereal intercrop systems with Cajanus cajan, Crotalaria juncea Tephrosia vogelii combination compound D (10% N, 20% P2O5, 10% K2O) urea (46% N) recommended rate (200 kg ha-1) half (100 ha-1). Composted cattle manure Fundikila, special plant biomass technique, inputs under category. conventional category treatment to which only chemical fertilizer was applied. Urease determined surface samples (0-20 cm) collected after 3 years. laboratory incubation study conducted over 13 weeks. incubation, an additional no input applied included as control. Application organic significantly increased potentially mineralizable (No) by 127% 256% LS 51% 131% SCL comparison Similarly, cumulative mineralized (Ncum) twice or thrice higher where been No followed order > control, mineralization constant (k) control both soils. than SCL. Higher rates resulted high Ncum yield. Maize yield positively correlated Ncum, but inversely amount (%Nmin). stimulated application suppressed fertilizers. type inputs; fertilizers; texture are factors influencing largely influenced fertilizer, not texture.