Cultivars and Nitrogen Application Rates Affect Yield and Nitrogen Use Efficiency of Wheat in Hot Arid Region

Abstract

The poor nitrogen use efficiency (NUE) in crops increases input costs and environmental problems. Selection of efficient cultivar and using cultivar-specific nitrogen rate are important strategies to improve NUE. A three-year field experiment was conducted to assess yield and NUE of three wheat cultivars (WH-147, Raj-1482, PBW-343) under six levels of N (N0, N40, N60, N80, N100 and N120 kg ha-1) in hot arid conditions at Rajasthan, India. The cultivar, nitrogen rate, and cultivar 9 nitrogen rate effects were detected significant for growth, yield components, yield and NUE. PBW-343 had 5 and 18 % higher yield as compared to Raj-1482 and WH-147, respectively. Application of N enhanced growth, yield components, and yield. Averaged over cultivars and years, the grain yield with N40, N60, N80, N100, and N120 was 32, 78, 118, 133, and 137 % higher as compared to N0. Response to N rates was cultivar specific; PBW-343 had the greatest yield with N100 and N120, whereas at lower N rates (N0, N40) WH-147 and Raj-1482 had higher yield as compared to PBW-343. The PBW-343 had 45–48 % greater agronomic, and 21–22 % greater apparent recovery efficiencies of N than other cultivars. Results suggest that selection of suitable cultivar and adjusting cultivar –specific N application rates is vital for optimizing grain yield and NUE for wheat crops.