STUDIES ON THE INTEGRATED NUTRIENT AND WEED MANAGEMENT PRACTICES ON GROWTH, YIELD AND ECONOMICS OF RICE (ORYZA SATIVA L.).

A comprehensive study was made in irrigated rice to optimise the integrated nutrient and weed management practices for augmenting rice productivity, at Annamalai University, Experimental Farm, Annamalai Nagar, Tamil Nadu, India. The experiment was laid out in split plot design with three replications. The details of the treatment in main plots are M₁ - Un weeded control, M2- Hand weeding (HW) twice at 20 and 40 DAT (Farmers practice), M₃ - Butachlor 1.25 kg a.i ha^-1 + one hand weeding (25 DAT), M4 - Pretilachlor 0.75 kg a.i ha^-1 + one hand weeding (25 DAT) and the sub plots S0 - Absolute control (no organic and inorganics), S1 - RDF through inorganic fertilizers (150: 50: 50 kg N, P₂O₅, K₂O), S₂ - 75% recommended dose of N + recommended dose of P and K + 25 % N on equivalent basis of composted vermicompost, S₃ - 75% recommended dose of N + recommended dose of P and K + 25 % N on equivalent basis of composted pressmud, S₄ - 75% recommended dose of N + recommended dose of P and K + 25 % N on equivalent basis of water hyacinth compost. The results of the study evidently proved that application of pre- emergence herbicide of pretilachlor 0.75 kg a.i. ha^-1 + one hand weeding at 25 DAT along with application of 75% recommended dose of N + recommended dose of P and K (112.5: 50: 50 kg N, P₂O₅ and K₂O ha^-1) + 25% N on equivalent basis of vermicompost (1400 kg ha^-1) as an agronomically efficient, eco friendly and economically viable technology for improving growth, yield and economics of rice. The lowest values for plant height, LAI at flowering, No. of tillers hill^-1, and DMP and yield attributes and yield was observed in the treatment M₁S₀ (unweeded control x no organic/inorganics) at all the stages of observation However, in both the crops treatment M₂ S₀ was statistically on par with M1S0 at 20 DAT. [ABSTRACT FROM AUTHOR]