Improving Halosulfuron Performance in Transplanted Plasticulture Tomato with Trifluralin and Oxyfluorfen Tank Mixes

Abstract

Halosulfuron is labeled for use under plastic for freshmarket tomato (Lycopersicon esculentum Mill.), and has significantly improved management of yellow nutsedge. Halosulfuron is not labeled for control of grasses. There is a need to determine how halosulfuron weed control can be improved and determine its application timing flexibility. Experiments were conducted at two locations to evaluate halosulfuron, applied alone or in tank-mixes with trifluralin or oxyfluorfen, at intervals shorter than label recommendations, and to determine efficacy and crop safety in plasticulture fresh-market tomato in Kentucky, USA and in Uruguay. Halosulfuron, trifluralin, and oxyfluorfen were equally safe to plants when applied at 0 or 7 days before transplanting tomato. Yields at both locations indicated that addition of trifluralin or oxyfluorfen to halosulfuron had no negative effect on tomato plant size and total yields. Yields were less with halosulfuron applied alone than in tank mixes with trifluralin or oxyfluorfen. Trifluralin and oxyfluorfen are potential tank mix partners with halosulfuron for use under plastic mulch. It appears that halosulfuron alone or in tank mixes is safe for application at intervals shorter than current label recommendations.