Effect of Nutrient and Weed Management Practices on Weed Dynamics and Productivity of Aromatic Rice in Semi-arid Region of Bihar

A field experiment was conducted during kharif season of 2017 at Dr. Rajendra Prasad Central Agricultural University, Pusa, Samastipur (Bihar) to investigate the “Effect of nutrient and weed management practices on weed dynamics and productivity of aromatic rice’’. The experiment was laid out in split-plot design and was replicated thrice. The treatments comprised three nutrient levels viz., N1= 100% RDF; N2=75% RDF + FYM 5 t/ha; N3=50% RDF + FYM 10 t/ha in main-plot, and six weed management practices viz., W1 = Brown manuring; W2= Bispyribac- sodium @ 25 g/ha as post emergence; W3= Chlorimuron ethyl + Metsulfuron methyl (Almix) @ 4 g/ha at 20 days after transplanting (DAT); W4= Pyrazosulfuron @ 25 g/ha; W5=Weed free; W6= Weedy check in sub-plot. The results revealed that treatment N1 recorded the maximum- recorded the grain yield of rice. Among weed management practices, treatment W5 recorded the maximum grain yield of rice. Weed population and weed dry matter were found maximum in N3. Weed control efficiency and weed index was the maximum in W5 and W6 respectively. Thus, it may be concluded that the nutrient level N1 is superior to N2 & N3. Secondly, high cost involved in manual weeding makes herbicidal treatments more viable proposition. The weed management practice W2 is a most effective for transplanted aromatic rice.