Evaluation of the Efficacy of Selected Herbicides on Weeds and Yield in Direct Seeded Tomato

This experiment was conducted in 2006 and 2007 at Agricultural Research Centers of Safi Abad of Dezful, Isfahan and Tehran (Karaj), I. R. Iran, to evaluate the efficacy ofselectedherbicides on weeds and yield of direct seeded tomato. The complete randomized block design was used with 9 treatments in three replications. Treatments included: pre-emergence and post emergence application of metribuzin (Sencor® 70% WP) at 4-leaf stage of tomato at 0.75 and 1 kg/ha, preplant incorporated application of oxyfluorfen (Goal® 24% EC) at 2 kg/ha, pre-plant incorporated application of napropamide (Devrinol® 45% FL) at 2.5 and 4.5 kg/ha, weedy and weed free checks. The experimental results at Safi Abad of Dezful for the reduction of total weed density indicated, pre-emergence application of metribuzin at 1 kg/ha and oxyfluorfen were the most effective herbicide treatments. Also weed free check and post-emergence application ofmetribuzin at 0.75 and 1 kg/ha, were the most effective treatments in increase the yield of tomato fruits. In Isfahan, in reduction of the total weed density, oxyfluorfen and post-emergence application of metribuzin at 1 kg/ha and in tomato yield increase, weed free check, napropamide at 4.5 kg/ha, pre and postemergence application of metribuzin at 0.75 and 1 kg/ha, respectively, were the most effective herbicide treatments. The results of Karaj showed that pre-emergence application of metribuzin at 1 kg/ha and oxyfluorfen in reduction of total weed density, and for tomato yield increase weed free check, pre-emergence application of metribuzin at 1 kg/ha and oxyfluorfen, were the most effective herbicide treatments.