Assessment of urea briquette application for maximization of rice yield and nitrogen use efficiency in Inceptisol

Abstract

Assessment of Urea Briquette Application for Maximization of Rice Yield and Nitrogen use Efficiency in Inceptisol” was conducted during kharif-2020 at Krishi Vigyan Kendra, Mahasamund, Chhattisgarh. The experiment was comprised of eight treatments involving different levels of nitrogen application through urea briquette and prilled urea viz T1: N0:P60:K40 T2: N75 (UB) T3: N100 (PU) T4: N100 (UB) T5: N125 (PU) T6: N125 (UB) T7: N150 (PU) T8: N150 (UB) and conducted in block randomized design with three replications Rice was used as test crop with cultivar “Rajeshwari”. Different nitrogen levels applied through placement of urea briquette and prilled urea broadcasted, phosphorus and potash @ 60 kg P2O5 ha-1 and 40 kg K2O ha-1 respectively. The soil of experiment site was sandy loam in texture with pH (6.1), electrical conductivity (0.11 dsm-1), organic carbon (0.41%), available N (137.98), available phosphorus (12.46) and available potassium (238.88) kg ha-1. Application of urea briquette @ 150 kg N ha-1 showed significant higher yield attributing parameters viz, plant height, effective tillers-1 and number filled grains panicle-1 as compared to other treatments. Grain and straw yields of rice were significantly increased by different levels of applied nitrogen through urea briquette and prilled urea and grain yield ranged from 32.66 to 68.77 q ha-1 and straw yield ranged from 38.11 to 89.87 q ha-1 under treatment (T1) N0 to (T8)150 kg N ha-1 (UB). The highest total N, P and K uptake were recorded 105.35, 19.18, 122.48 kg ha-1 respectively under applied nitrogen @ 150 kg ha-1 under treatment (T8) and lowest N, P & K uptake 48.27, 7.75, 55.93 kg ha-1 were obtained under treatment (T1) N0:P60:K40 respectively. Overall nitrogen use efficiency (%) decreased with increasing levels of applied nitrogen from 125 to 150 kg N ha-1. The highest NUE (39.22%) was recorded through urea briquette applied N @ 125 kg ha-1 under treatment (T6) and the lowest (28.67%) noted under treatment (T3) applied N @ 100 kg ha-1 through prilled urea respectively.After harvest of rice crop different physico-chemical properties of soil were analyzed and the findings revealed that soil pH, EC and organic carbon were not significantly influenced with levels of applied nitrogen through UB and PU. Available nitrogen content increased and phosphorus and potassium decreased in soil with increased levels of applied nitrogen irrespective UB and PU. The highest available nitrogen (180.33 kg ha-1) recorded under applied N 150 kg ha-1 through UB.