Impact of chemical fertilizer and composts application on growth and yield of rice in Northeast India

Formulation of effective fertilizer management practice is crucial for sustainable rice cultivation. Prolonged application of chemical fertilizers can result in N loss into the environment, causing harmful effects. Application of organic fertilizer acts as an alternative source of nutrient supply for rice cultivation. The present study evaluates growth and productivity of rice due to sole application of three different types of composts, along with their combined application with chemical fertilizer. The three types of composts are compost made from organic component of municipal solid waste, vermicompost made from a combination of rice straw and cow manure and compost made from a floating mat found in Loktak Lake consisting of a heterogeneous mass of soil and aquatic macrophytes locally known as phumdi. Eight different kinds of treatments were maintained to determine growth and yield of a local rice variety (RCM-13), in field condition for two growing season in two years: (1) Control, no fertilizers applied (2) MSWC (Municipal solid waste compost, 100%) (3) VC (Vermicompost, 100%) (4) PC (Phumdi compost, 100%) (5) CF (Chemical fertilizer, 100%) (6) MSWC + CF (50%+50%) (7) VC + CF (50%+50%) (8) PC + CF (50%+50%) arranged in randomized block design. The combined application of phumdi compost and chemical fertilizer (50%+50%) produced 33.6% more grain yield and 26.21% more straw yield compared to 100% application of chemical fertilizer. Application of 50%+50% of municipal solid waste compost with chemical fertilizer and 50%+50% of vermicompost with chemical fertilizer were also able to produce more grain yield compared to sole application of chemical fertilizer, with an increase of 5% and 13.16% respectively. The finding indicates substituting 50% of chemical fertilizer with composts can enhance production of the present rice variety. Moreover, utilization of phumdi in the form of compost can also help in the management of the lake from further eutrophication.