Sandeep Singh, S.B. Singh, Brijesh Kumar, Shreya Roy, Ashish Kumar, Mayank Mani Tripathi1, Abhinav Kumar, Meghnath Singh Dhurwe and Shushil Kumar Yadav
Abstract
A field experiment was conducted during the rabi seasons of 2023â24 and 2024â25 at the Agronomy Research Farm, Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya (U.P.), to evaluate the comparative impact of chemical and manual weed management practices on nutrient uptake efficiency and grain yield of oat (Avena sativa L.). The study consisted of ten weed management treatments, including pre-emergence applications of pendimethalin and oxyfluorfen, post-emergence applications of metsulfuron-methyl and 2,4-D, sequential herbicide combinations, manual weeding at 20 and 40 DAS, hand hoeing, and an untreated weedy check. Observations on grain yield and N, P2O5 and K2O uptake in grain and straw were recorded to quantify treatment effectiveness. The results demonstrated that the sequential application of pendimethalin @ 750 g ha-¹ (PE) followed by metsulfuron methyl @ 4 g ha-¹ at 20 DAS (T) consistently produced the highest grain yield (31.6 and 31.93 q ha-¹) during both years, closely followed by manual weeding at 20 and 40 DAS (T). These treatments also recorded the maximum uptake of N, P2O5 and K2O in both grain and straw, significantly outperforming the single herbicide treatments. Manual weeding proved highly effective but may be constrained by labour availability during peak seasons. The lowest yield and nutrient uptake were noted in the weedy check, highlighting severe competition and nutrient depletion under unmanaged weed growth. Overall, the findings indicate that integrated weed management involving a pre-emergence herbicide followed by a selective post-emergence application offers superior weed suppression, enhanced nutrient uptake efficiency and improved grain productivity in oat. The sequential herbicidal approach, particularly pendimethalin followed by metsulfuron methyl, is recommended as an efficient and sustainable strategy for oat cultivation in the Eastern Uttar Pradesh agroclimatic conditions.