Effect of trifluralin on fusarium wilt in flax

Abstract

The effects of the herbicide trifluralin on the incidence of flax wilt and agronomic traits were investigated in several flax cultivars in established fields with high, and low infestation of F. oxysporum f.sp. lini. Trifluralin was applied in the fall and seeding carried out the following spring. Trifluralin negatively interacted with fusarium wilt, reducing plant emergence by 42–68%, and the final plant population by 36–60% in several cultivars. Trifluralin reduced the incidence of post-emergence wilt and late-wilt. The reduced post-emergence disease incidence was perhaps due to poor emergence and low plant population which left fewer plants to be infected. The interaction of trifluralin with this fungus reduced yield (17–60%) in most cultivars in highly infested fusarium soil. In low-infested soil, trifluralin significantly increased yield in most cultivars (8–44%). The significant trifluralin and wilt interaction also resulted in increased plant height. Key words: Linum usitatissimum, Fusarium oxysporum f.sp. lini., trifluralin, flax wilt