Impact of Establishment Techniques and Weed Management Strategies on Chemical Properties of Soil in Wet Direct-seeded Winter Rice

Aim: The aim of the experiment was to check the effect of establishment techniques and weed management strategies on chemical properties of soil.

Study Design: The design of the experiment was split plot design.

Place and Duration of Study: Assam Agricultural University-Assam Rice Research Institute, Titabar, Assam, India, during the sali season of 2022-2023.

Methodology: A total of three establishment techniques viz., broadcasting , drum seeding and line sowing in main plot and six different weed management practices namely hand weeding at 20, 40 and 60 DAS , pyrazosulfuron-ethyl @ 30 g/ha at 2 DAS fb bispyribac-Na @ 25 g/ha at 25 DAS, pyrazosulfuron-ethyl @ 30 g/ha at 2 DAS fb mechanical weeding at 40 and 60 DAS, pyrazosulfuron-ethyl @ 30 g/ha at 2 DAS fb bispyribac-Na @ 25 g/ha at 25 and 45 DAS , weed free check and weedy check in sub plot , respectively. Where DAS=Days after sowing and fb=followed by.

Results: Results revealed that among various establishment techniques, drum seeding technique resulted in the lowest available nitrogen (237.87 kg/ha), phosphorus (21.67 kg/ha) and potassium (150.15 kg/ha) in the soil, respectively after harvest. Moreover, under various weed management practices, pyrazosulfuron-ethyl @ 30g/ha at 2 DAS fb bispyribac-Na @ 25 g/ha at 25 and 45 DAS showed lowest nitrogen (236.87 kg/ha), phosphorus (21.37 kg/ha) and potassium (149.23 kg/ha) in the soil, respectively after harvest which was next to weed free check.

Conclusion: Combined application of drum seeding along with pyrazosulfuron-ethyl @ 30g/ha at 2 DAS fb bispyribac-Na @ 25 g/ha at 25 and 45 DAS can facilitate optimum plant population of crop with dense canopy cover, resulting in higher uptake of essential minerals and nutrients by the crop, enhancing the overall yield of rice while minimizing weed population throughout the growing period.