Integrated Weed Management in Sunflower Using a Hybrid Mixture and Reduced Herbicide Dose

Herbicides have been the primary tool for weed management to ensure food security for a growing global population. However, excessive herbicide use raises concerns about environmental contamination, developing herbicide-resistant weeds, and potential human health risks. This necessitates the exploration of ecologically sustainable weed management practices in agriculture. The present study explored the potential of inter-field biodiversity (by sunflower hybrid mixture) to reduce weed competitiveness along with reduced herbicide dose usage. The experiment was conducted at the Agronomic Research Area, University of Agriculture, Faisalabad, in the autumn seasons of 2022 and 2023 under a randomized complete block design (factorial arrangement). The experimental factors consisted of a hybrid mixture (FH-701 and FH-648) and monocultures of each of the individual sunflower hybrids with incremental doses of lactofen and quizalofop-p-ethyl as tank mixture. The recommended dose of herbicides along with the sunflower hybrid mixture usage caused impressive weed biomass reduction (81–83%) than monoculture (72–80%). Notably, the sunflower hybrid mixture maintained satisfactory weed suppression (up to 75%) even at 75% herbicide label dose (Lactofen: 135 g a.i. ha −1 , quizalofop-p-ethyl: 281.25 g a.i. ha −1 ). The sunflower hybrid mixture demonstrated strong yield performance, (83% of control), similar to sunflower hybrids monoculture. Importantly, the sunflower hybrids mixture maintained a statistically similar yield (2.29–2.36 t ha −1 ) at 75% herbicide label dose. The economic advantage of the mixture was confirmed by a consistently high benefit-to-cost ratio, ranging up to 1.62, exceeding that of sunflower hybrid monoculture practices with full herbicide application. These findings suggest that the sunflower hybrid mixture offers a promising approach for effective weed, maintaining yield, and promoting economically sustainable sunflower production with reduced reliance on herbicides.