Weed Control and Selectivity of Four Herbicides Applied in Pre-Emergence on Two Sunflower Cultivars

The sunflower (Helianthus annuus L.) is an oleaginous plant that shows high suitability for cultivation in Brazil. However, the performance of crop influenced by factors such as weed interference, mainly because few selective herbicide options. Thus, objective this study was to evaluate control and selectivity four pre-emergent herbicides applied two cultivars sandy clayey soils. Two field experiments were conducted a randomized block design with 2 × 6 factorial scheme, (CF 101 M 734) six treatments S-metolachlor (1920 g a.i. ha−1), sulfentrazone (150 flumioxazin (40 trifluralin (1780 ha−1) controls, one weeding other without application, soils contrasting textures (sandy clayey). No injury symptoms observed both cultivars, regardless soil texture. cultivar 734 exhibited highest values agronomic parameters evaluated. treatment provided more than 90% weeds 64% soil. yield lower all tested, since they did not interfere grain yield.