Effect of Integrated Nutrient Management and Foliar Spray of Zinc in Nanoform on Rice Crop Nutrition, Productivity and Soil Chemical and Biological Properties in Inceptisols

The impact of combined use of inorganic and organic nutrients in supplementation with foliar spray of zinc in nanoform on rice has never been studied to date. It was postulated that such combination could ensure better growth and yield in Inceptisols through better availability of nutrients and also enhanced soil biological activities. Eight treatment combinations (variable levels of recommended dose of nitrogen (RD N ), from farmyard manure (FYM) and/or nano zinc) were tested on rice (var. Shatabdi (IET 4786)). Standard growth and yield parameters, pigment analysis, available soil nutrients status, their concentration and uptake by plant, soil microbial status and dehydrogenase enzyme activity were analysed. The maximum grain yield (5.06 t ha −1 ) was obtained from 75% RD N from commercial chemical fertilizer + 25% RD N from FYM + foliar nano zinc spray treatment exhibiting the maximum number of panicles m −2 and a higher number of grains panicle −1 that increased the grain yield by 8.82% compared with that of the 100% RD N from chemical fertilizer treatment (4.65 t ha −1 ). Sole application of nano zinc resulted in 4.01 t ha −1 grain yield that was 17.6% improved over control. Better microbial population in soil was ensured by enhancement in dehydrogenase enzyme activity in FYM-treated plots than 100% recommended dose of fertilizer at all growth stages of rice. Application of zinc in nanoform under INM system not only enhanced the productivity of rice and zinc use efficiency but also ameliorated soil health by improving soil chemical as well as biological properties.