Performance and nitrogen use efficiency of grain sorghum through method and time of nitrogen application under semi-arid environment

Abstract

The present field investigation was carried out for three consecutive kharif season of 2015, 2016 and 2017 at research farm of Agricultural Research Sub Station Diggi, Tonk to improve nitrogen use efficiency through method and time of nitrogen application and performance of sorghum under semi arid environment of Rajasthan, India. The experiment was laid out in factorial randomized block design consisted of five nitrogen scheduling treatments viz. N1 (50+50), N2 (50+25+25), N3 (25+50+25), N4 (25+50+15+10), N5 (25+45+5+15+10), and two genotypes viz CSH-16 and CSV-20 and replicated thrice. The results revealed that the application of nitrogen with 50% N at sowing + 25% N at 30 DAS + 25% N at boot leaf stage recorded significantly maximum plant height and dry matter accumulation of sorghum. The application of nitrogen with 25% N at sowing + 50% N at 30 DAS + 15% N at boot leaf stage+10% at Grain filling stage recorded minimum plant height and dry matter accumulation of sorghum. The significantly maximum number of grains/cob (3136.3) and test weight (28.0 g) were registered with application of nitrogen with 50% N at sowing + 25% N at 30 DAS + 25% N at boot leaf stage. However, crop supplied nitrogen with the 50% N at sowing + 50% N at 30 DAS recorded statistically similar results for these yield attributes. The grain, stover and biological yields of sorghum due to different method and time of nitrogen application treatments were found statistically at par. The application of nitrogen with 50% N at sowing + 25% N at 30 DAS + 25% N at boot leaf stage resulted in increased mean gross return (Rs. 89159). Among the method and time of nitrogen application treatments, the highest cost of cultivation (₹26301), gross returns (₹89159) net returns (₹62858) and B:C ratio (2.39) were recorded with application of nitrogen with 50% N at sowing + 25% N at 30 DAS + 25% N at boot leaf stage. The experimental results supported the hypothesis that nitrogen use efficiency could be improved by method and time of nitrogen application. Proper method and time of nitrogen application have positive impact on growth, productivity and profitability of grain sorghum. Thus, it is concluded that improvement of nitrogen use efficiency through method and time of nitrogen application can be advocated as sustainable strategy for enhancing productivity and profitability of sorghum cultivation under semi arid environment.