Managing neem (Azadirachta indica)-coated urea and ordinary urea in wheat (Triticum aestivum) for improving nitrogen-use efficiency and high yields

Abstract

Modifications in fertilizer source and/or management can lead to reduced losses of N, high wheat yields and increased fertilizer N-use efficiency. Relative performance of neem (Azadirachta indica A Juss)-coated urea vis-à-vis ordinary urea applied to wheat (Triticum aestivum C. emend Fiori & Paol.) was studied when applied at different levels (48, 96 and 120 kg N/ha), drilled in between rows as a single dose of 96 kg N/ha and when applied in 3 split doses (48, 48 and 24 kg N/ha). The field experiments were carried out at 2 locations, i e Ludhiana–sandy loam soil and Gurdaspur – clay loam soil during 2005–08. When nitrogen was applied in 2 equal split doses at the time of sowing and first irrigation, the neem coated urea did not out perform urea in increasing grain yield at any level of N application at both the locations. Performance of neem coated urea @96 kg N/ha drilled during sowing of wheat was better than neem-coated urea applied @ 120 kg N/ha in 2 split doses at Ludhiana. Better performance of urea and neem-coated urea applied in 3 rather than 2 split doses only in coarse-textured soil at Ludhiana suggests that losses of applied N via leaching can be substantial as compared to in the fine textured soil at Gurdaspur. This study suggests that neem-coated urea can lead to improved N-use efficiency when applied either in 3 split doses or drilled between rows as a single dose in coarsetextured soils rather than in fine-textured ones.