Effect of Nitrogen management on yield, yield attributes & quality of Forage Sorghum (Sorghum bicolor L.)

Abstract

A field experiment was conducted during kharif season 2022 at Crop Research Centre of Sardar Vallabhbhai Patel University of Agriculture & Technology Meerut (U.P.) India to study the “Effect of Nitrogen management on yield, yield attributes & quality of Forage Sorghum (Sorghum bicolor L.)”. The soil of the experimental field was well-drained, sandy loam in texture, and slightly alkaline. It was low in organic carbon and available nitrogen but medium in phosphorus and potassium. The treatments were; three quantity of nitrogen viz. 80 kg N ha-1, 120 kg N ha-1 and 160 kg N ha-1 and three time of application i.e. ¼ N before sowing + ½ N at 30 DAS + ¼ N at 60 DAS, ½ N before sowing + ½ N at 60 DAS and ¼ N before sowing + ¼ N at 30 DAS + ¼ N at 60 DAS + ¼ N at 90 DAS was laid out in Randomized Block Design (Factorial) with three replications. Results of the experimental field were revealed that growth parameters viz., plant height, number of shoots per plant, leaf stem ratio, dry matter content per plant, dry matter accumulation were significantly maximum in treatment 160 kg N ha-1 which was statistically at par with 120 kg N ha-1. The green fodder and dry fodder yield (153.3; and 39.5 q ha-1) were found higher under treatment 160 kg N ha-1. The maximum cell content and total ash content (%) (48.5 & 46.48 and 11.8 & 13.1) were recorded in 160 kg N ha-1. 160 kg N ha-1 also recorded highest available NPK (240.74 & 228.3, 16.48 & 14.6 and 253.54 & 243.2kg ha-1). Treatment 160 kg N ha-1 had 30.3% cost of cultivation over 80 kg N ha-1. The maximum gross return was recorded into the treatment 160 kg N ha-1 followed by 120 kg N ha-1. Among time of application, treatment ¼ N before sowing + ¼ N at 30 DAS + ¼ N at 60 DAS + ¼ N at 90 DAS recorded tallest plants (100.6 cm) with highest number of shoot per plant (4.4), leaf stem ratio (0.24) and dry matter accumulation (81.3 g m-2). The highest green and dry fodder yield were significantly higher in ¼ N before sowing + ¼ N at 30 DAS + ¼ N at 60 DAS + ¼ N at 90 DAS. Among different time of application maximum net return (Rs.85060) was found in ¼ N before sowing + ¼ N at 30 DAS + ¼ N at 60 DAS + ¼ N at 90 DAS which is found at par with ¼ N before sowing + ½ N at 30 DAS + ¼ N at 60 DAS (Rs.83069). However, benefit cost ratio was found to be highest (3.32) with ¼ N before sowing + ¼ N at 30 DAS + ¼ N at 60 DAS + ¼ N at 90 DAS which was closely related with ¼ N before sowing + ½ N at 30 DAS + ¼ N at 60 DAS i.e. (3.31) and lowest with ½ N before sowing + ½ N at 60 DAS (2.81). To achieve highest green and dry fodder yield of forage sorghum with higher profit, application of 160 kg N ha-1 and ¼ N before sowing + ¼ N at 30 DAS + ¼ N at 60 DAS + ¼ N at 90 DAS are better option.