Influence of Nitrogen Levels and Weed Management Practices on Soil Quality of Wetland Rice

Abstract

Rice (Oryza sativa L.) is one of the most popular cereal crops serves as the staple food for world’s half of the population. Nutrients and weeds are two important factors that determine the productivity of wetland rice. Nitrogen (N) is major nutrient that contributes in rice production. Weeds are the major constraint limiting high productivity of rice. Weeds may remove considerable quantity of nutrients besides competing for light; space and moisture thus become a major constraint in wetland rice. Considering these, a field experiment was conducted for two successive kharif seasons of 2018 and 2019 at Agricultural Research Farm, B.H.U., Varanasi, UP (India). The study included influence of nitrogen levels and weeds management practices (WMP) post harvest soil quality of wetland rice. The experiment was laid out in split plot design involving five nitrogen levels viz. control, 60 kg N ha-1 through inorganic, 60 kg N ha-1 as farmyard manure (FYM), 90 kg N ha-1 & 120 kg N ha-1 in main plots and four weed management practices viz. Azolla 2 t ha-1, BGA 1.25 kg ha-1, two hand weeding (2HW) at 20 & 40 days after transplanting (DAT) along with weedy in sub plots and replicated thrice. The results showed that the FYM treated plots exhibited maximum residual NPK and organic carbon with comparatively less pH in post harvest soil of wetland rice. Post harvest soil studies indicated that among weed management practices Azolla facilitated higher residual NPK and organic carbon and least pH in wetland rice field.