Evaluation of Some Sulfonylurea Herbicides in Sweet Sorn (Zea mays L.) Weed Control

To evaluate the performance of new Sulfonylurea herbicides in sweet corn weed control, a factorial experimental research was carried out based on a completely randomized block design with three replications in Agriculture and Natural Resources Research Center of Khorasan Razavi in 2012. The first and the second factor, were sweet corn varieties and chemical control treatments respectively. The sweet corn varieties included KSC403su, Merit and Chase. The chemical control treatments included Nicosulfuron (Cruz), Nicosulfuron (Cruz) + Bromoxinyl + MCPA (Brimicide MA), Foramsulfuron (Equip), Rimsulfuron + Nicosulfuron (Ultima), Mesotrion + S-Metolacholor + Terbuthlazine (Lumax 537.5 SE), with weed free, and weed infested in each block. Sampling was done 4 weeks spraying each plot. The result showed that red root pigweed, common purslane, field bindweed, common lambsquarters, purple nutsedge, black night shade dry weight were reduced significantly by all herbicides compared with weedy check. Among the sweet corn varieties, the highest and the lowest weeds density and dry weight resulted by Chase and KSC403su, respectively. Mesotrion+ S-Metolacholor+ Terbuthlazine herbicide had sound effect on dry weight reduction of red root pigweed, common purslane, field bindweed, common lambsquarters, purple nutsedge, black nightshade, with highest control of common lambsquarters. Also, red root pigweed, common purslane and field bindweed should satisfactory control by nicosulfuron and nicosulfuron+ brimicide MA applied, whereas nicosulfuron + rimsulfuron had suitable effect on common purple nutsedge.