POSTEMERGENCE CONTROL OF BROADLEAF WEEDS IN TOMATO (LYCOPERSICON-ESCULENTUM)

Greenhouse and field experiments were conducted to evaluate the control of eastern black nightshade and velvetleaf in tomato with bentazon, metribuzin, pyridate, and acifluorfen. Metribuzin controlled velvetleaf but not eastern black nightshade, whereas pyridate controlled eastern black nightshade but not velvetleaf. A combination of metribuzin + pyridate controlled both weeds, but caused tomato injury 4 wk after application. Bentazon neither controlled the weeds nor injured the crop. Acifluorfen controlled both eastern black nightshade and velvetleaf. Diammonium phosphate and oxysorbic (5 POE) improved bentazon and acifluorfen activity against velvetleaf. Although initial crop injury from some treatments applied prior to fruit initiation was severe, the crop recovered and there were no reductions in fruit weight compared with the control. However applying acifluorfen with oxysorbic (5 POE) during fruit development reduced yield 50%.