Yield, water, radiation and nitrogen use efficiencies of wheat (Triticum aestivum ) as influenced by nitrogen levels in a semi-arid environment

Abstract

A field experiment was conducted during the winter ( rabi) season of 200910 and 201011 on a sandy-loam soil in New Delhi, to study the effect of nitrogen levels on the water, radiation and nitrogen-use efficiencies of wheat [ Tr iticum aestivum (L.) emend. Fiori. & Paol.] cultivars. The treatments comprising 2 wheat cultivars (PBW 502 and DBW 17) and 3 nitrogen levels (N : 0kg N/ha, N : 60 kg N/ha and N : 120 kg N/ha) were laid out in fac- 0 60 120 torial randomized block design (RBD). Both cultivars were statistically at par for grain yield, above-ground biomass yield, water-use efficiency (WUE) and radiation-use efficiency (RUE). Treatments N registered 71% and 25% 120 higher grain yield than N and N treatments respectively. Water-use efficiency (WUE) of N (9.92 kg/ha/mm) was 0 60 120 significantly highest, followed by N (8.40 kg/ha/mm) and N (6.56 kg/ha/mm) treatments. Similarly, radiation-use 60 0 efficiency (RUE) of N (2.49 gm/MJ) was significantly higher than N (1.90 gm/MJ) and N (1.85 gm/MJ) treat- 120 60 0 ments. The partial factor productivity of nitrogen (PFPN) of the cultivar PBW 502 (48.96 kg grain/kg nitrogen ap- plied) was significantly higher than that of DBW 17 (42.23 kg grain/kg nitrogen applied). Nitrogen @ 60 kg/ha (N ) 60 showed significantly higher PFPN (56.08 kg grain/kg nitrogen applied) than N (35.10 kg grain/kg nitrogen ap- 120 plied) treatment. Therefore, cultivar PBW 502 or cultivar DBW 17 can be grown with 120 kg N/ha for obtaining higher grain yield, above ground biomass, WUE and RUE in the semi-arid tropical environment of Delhi region.