Site specific fertilizer recommendations for maize (Zea mays L.) grown in reddish brown earth and reddish brown latasolic soils.

Site specific fertilizer recommendations optimize crop production while minimizing nutrient losses. This study was conducted to identify soil fertility constraints of Reddish Brown Earth (RBE) in DL1b and Reddish Brown Latosolic (RBL) soil in IM3c and to formulate site specific fertilizer recommendations for Maize ( Zea mays L. ). Low productive fields from Mahailluppallama (MI) and Dodangolla (KS) in Sri Lanka were selected based on available farm records and soil fertility survey. Soil samples were analyzed for basic soil properties using standard methods and available nutrients (NH 4 + -N, P, K, Ca, Mg, S, Fe, Mn and Zn) were determined using multi-element extractions. The nutrient concentrations for optimum treatments were formulated based on available nutrients and fixation capacity of nutrients. The formulated nutrient requirements were tested in a greenhouse experiment using missing element technique. Soil nutrient analysis indicated the deficient levels of N, P, S, Ca, Zn and Cu for RBE soils and N, P, K, S, Ca, Zn, Cu and Mn for RBL soil. Lower fixation capacity of P and higher fixation capacity of S were observed in RBL, than that of RBE. In the greenhouse experiment, both soils showed the highest dry matter yield in the optimum nutrient treatment and significant differences were observed in minus treatments of Ca, S and Zn for RBE and P, Ca, S and CaCO3 for RBL soil. Site specific fertilizer requirements for maize were identified for the two tested soils, which could be utilized for achieving potential yield. Tropical Agricultural Research Vol. 25 (3): 287-297(2014)