Effectiveness of Different Herbicides on Growth, Yield and Weed Flora Control Indices of Onion

The effects of various herbicides on the economic performance, yield, and growth of onions were determined during the winter season of 2019-2020. Two field experiments were carried out at the Regional Agricultural Research Station (RARS), Jashore, and the Agronomy research field of the Bangladesh Agricultural Research Institute (BARI), Joydebpur, Gazipur. Various herbicides were evaluated through both pre- and post- planting applications. The findings demonstrated that the application of Full clear at 1125 g.a.i./ha (T₁) resulted in lower weed index and greater herbicide efficiency index, BCR, and weed control efficiency. This was followed by Pellet at 660 g.a.i./ha applied before transplanting (T₅), Bullet at 525 g.a.i./ha applied at the 2-3 leaf stage of weeds (T₄) and Penlin at 330 g.a.i./ha applied at the 2-3 leaf stage of weeds (T₂) at both locations. It was also found that hand weeding (T₆) was the best option for getting the maximum yield of onion, weed persistence index, weed management index, and agronomic management index across both sites. The study also found significant correlation matrix of the yield contributing traits and weed indices. Therefore, the study concludes that herbicide treatments T₁, T₅, T₄, and T₂ were effective in weed control and enhancement of the onion bulb yield.