Weed management in sunflower through sequential application of herbicides in Western Odisha

Field experiment was conducted during the winter seasons of 2014–15 and 2015–16 to study the effect of sole and sequential application of herbicides on weed growth and productivity of sunflower (Helianthus annuus L.). Echinochloa colona, Digitaria sanguinalis and Dactyloctenium aegyptium among grasses; Cyperus rotundus and Cyperus difformis among sedges and Cleome viscosa, Euphorbia hirta and Borreria hispida among broad-leaved weeds, were predominant throughout the cropping period. Weed competition resulted in 31.3% yield loss in sunflower. Sequential application of oxyfluorfen 250 g/ha at 3 days after seeding (DAS) followed by (fb) quizalofop-ethyl 50 g/ha at 20 DAS resulted in the lowest weed density (41/m²), total weed biomass (19.37 g/m²), maximum nutrient uptake, yield (2.1 t/ha) and benefit:cost ratio (1.82).