Evaluation of rice (Oryza sativa L.) varieties and hybrids in relation to different nutrient management practices for yield, nutrient uptake and economics in SRI

摘要

A field experiment was conducted during kharif 2010 at Directorate of Rice Research farm, Rajendranagar. The experiment was laid in split plot design replicated thrice to assess the performance of three rice varieties (Vasumathi, Krishnahamsa and KRH-2) in main plots and to find the best management practices with six nutrient management practices [100% RDN through inorganic fertilizer; 75% RDN (inorganic) + 25% RDN (organic) through vermicompost; 50% RDN (inorganic) + 50% RDN (organic) through vermicompost; 25% RDN (inorganic) + 75% RDN (organic) through vermicompost; 100% RDN (organic) through vermicompost; Control (No manure and no fertilizer)] in sub- plots under System of Rice Intensification (SRI).The results revealed that hybrid KRH-2 recorded significantly higher grain and straw yield as well as nutrient uptake. Among the different nutrient management options, application of 50 percent recommended dose of nitrogen (through urea) and remaining 50 percent RDN through vermicompost resulted in significantly higher grain (5520.8 kg/ ha) and straw yield (6264.9 kg/ ha) in addition to nutrient uptake (157.9,30.7 and 166 N, P and K kg/ha respectively) followed by 100 % RDN (through urea) application. In terms of economics, hybrid KRH-2 with 50% RDN (inorganic) + 50% RDN (organic) through vermicompost recorded, respectively, higher gross and net returns (Rs 70,013 and 46,398/ha) but the maximum B: C ratio (2.07) was found associated with the hybrid KRH-2 in combination with 100% RDN (through urea).