Effect of silicon on real time nitrogen management in a rice ecosystem

Abstract

Field experiments were conducted during Kharif season of 2009 on sandy loam soil at Doddajala, Bangalore, India of eastern dry zone soils of Karnataka to investigate the effect of silicon (Si) and nitrogen application on the growth and yield of rice, using Cv. BI-34, a medium duration genotype. The results revealed that higher grain and straw yield was noticed with application of calcium silicate at 2 t ha-1 along with application of N at 100 kg ha-1 recommended dose of fertilizer (RDF) followed by silica gel at 500 kg ha-1 over RDF under both aerobic and wetland rice conditions. The combined application of Si sources along with Leaf Colour Chart (LCC) based N application of 75 kg N ha-1 (Basal 30 kg N ha-1+LCC) under aerobic and wetland rice recorded on par grain and straw yield compared to RDF alone. Combined application of silicon and nitrogen significantly increased the effective number of tillers, number of grains per panicle, 1000-grain weight. Higher agronomical efficiency (AEN), recovery efficiency (REN), Partial factor productivity (PFPN) values were noticed with LCC based application along with calcium silicate at 2t ha-1 under both aerobic and wetland rice.