Asian Basic and Applied Research Journal

This study was conducted to evaluate the effects of mulching and combinations of different urea levels with rhizobium inoculation on weed infestation in groundnut (Arachis hypogaea L.) at the Oil Seed Crops Research Section, Department of Agricultural Research (DAR), Myanmar, during the post-monsoon seasons from December to March in 2024-2025 and 2025-2026. Field experiments were conducted using a split-plot design with three replications. The mulching treatments, consisting of rice straw mulch at 6000 kg ha⁻¹ and no mulch, were assigned to the main-plot factor, while combinations of different urea levels with rhizobium (Rh) inoculation (100% U without Rh, 100% U with Rh, 75% U with Rh, 50% U with Rh, and 25% U with Rh, and 0% U with Rh) were assigned to the sub-plot factor. Sinpadathar-11 was used as the tested variety. The weed density of grasses, sedges, and broadleaf weeds was lower with rice straw mulching than with no mulch in both experiments. Similarly, rice straw mulching resulted in lower weed dry weight for all weed groups compared with no mulch. Grasses and sedges accounted for a higher proportion of the relative weed density than broadleaf weeds under both mulching and no mulch conditions across both experiments. The combinations of urea levels with rhizobium inoculation and their interaction with mulching did not significantly influence most weed infestation parameters, except for broadleaf weeds at 75 DAS in the second experiment. Based on the results, rice straw mulching can be considered an effective and sustainable weed management practice for groundnut production during the post-monsoon season in the study area.