Assessment of Seeding Methods and Weed Management Practices on Weed Dynamics, Crop Performance and Profitability in Rice-Safflower System

Rice–safflower cropping systems face challenges related to crop establishment, rice-residue management and weed competition, which can adversely affect safflower productivity and profitability. A field experiment was conducted at the Research-cum-Instructional Farm of Indira Gandhi Krishi Vishwavidyalaya, Raipur, Chhattisgarh during the Kharif and Rabi seasons of 2019-20 and 2021-22 to assess the effects of sowing methods and weed management practices in a direct-seeded rice-based cropping system with rice residue retention on weed dynamics and productivity. During the Kharif season, rice was sown directly following standard agronomic practices, while during the Rabi season, safflower was grown using a split-plot design comprising three sowing methods namely zero seed drill, happy seed drill and normal seed drill (with soil preparation only by rotavator) in the main plots and three weed management practices namely chemical weed control, hand weeding twice and unweeded check in the subplots, with three replications. The happy seed drill resulted in significantly higher seed and stover yields of safflower (1381 and 3459 kg ha-1, respectively). Hand weeding twice resulted in higher seed and stover yields of safflower (1629 and 4050 kg ha-1, respectively). Weed density was lowest in the hand weeding twice treatment, with mean values of 3.61, 3.80 and 4.68 at 30, 60 and 90 days after sowing, respectively and a maximum weed control efficiency of 80.24% compared with unweeded check. Maximum gross returns (7.28 and 8.56 103 x ₹ha-1), net returns (4.72 and 5.60 103 x ₹ha-1), benefit–cost ratios (2.80 and 2.88), rice equivalent yield (mean value of 3909 and 4614 kg ha-1) system productivity (mean value of 8737 and 9442 kg ha-1) and production efficiency (mean value of 11.64 and 12.28 kg ha-1day-1) of safflower were recorded under happy seed drill and hand weeding twice.