Influence of nutrient levels and irrigation regimes on yield attributes, yield and WUE of transplanted rice under Tamirabarani command area

Abstract

Field experiment was conducted at Agricultural college and research institute, Killikulam during early pishanam (2019 to 2020) to find out the optimum level of nitrogen and irrigation regimes to enhance the yield and WUE of transplanted rice. The experiment was laid out in strip plot design and replicated thrice. The vertical strips consists of 3 irrigation regimes namely irrigation at 10 cm depletion of field water tube (FWT) from 10 DAT to 10 days prior to harvest (A1), irrigation at 15 cm depletion of field water tube (FWT) up to maximum tillering stage (30-35 DAT) and thereafter 10 cm depletion of field water tube (FWT) up to 10 days prior to harvest (A2) and continuous flooding (A3) and the horizontal strip consists of nutrient management practices such as 100% RDF alone (B1), 100% RDF along with recommended dose of GLM (B2), 125 % RDF (100% N through inorganic + 25% N through GLM) (B3), 150% RDF (100% N thorough inorganic + 50% N through GLM) (B4) and absolute control (B5). Green manure glyricidia was taken as GLM. Observations on yield attributes like productive tillers, number of grains and filled grains panicle-1, panicle length and 1000 grain weight, and also grain and straw yield were recorded. Total water consumed and water use efficiency also worked out for different treatment combinations. The obtained results showed that continuous flooding with application of 150% RDF (100% N through inorganic and 50% N through GLM) (A3B4) recorded highest yield attributes like panicle length, number of grains and filled grains per panicle, number of productive tillers and 1000 grain weight, grain yield of about 8571 kg ha-1 and straw yield of about 9347 kg ha-1. However WUE was higher in irrigation at 15 cm depletion of field water tube along with 150% (100% N through inorganic and 50% N through GLM) (A2B4) 9.12 kg ha-mm-1.