Effect of Formasulfuron + Isoxadifen-Ethyl in Combination with Urea for Weed Control in Maize (Zea mays L.).

ABSTRACT

            A field experiment investigated the effect of formasulfuron + isoxadifen-ethyl (F+IE), applied alone and in combination with urea, on weeds and yield of spring (March-May) and autumn (August-October) maize (Zea mays L.). Six treatments comprised of control, manual hoeing, F+IE 1125 g a.i. ha^-1, F+IE 1125 g a.i. ha^‑1 + 1% urea, F+IE 1125 g a.i. ha^-1 + 2% urea and F+IE 1125 g a.i. ha^-1 + 3% urea. The F+IE solution was sprayed post – emergence 20 days after sowing. Manual hoeing, and formasulfuron + isoxadifen-ethyl @1125 g a.i. ha^-1 combined with 3% urea were the most effective treatments for controlling Cyperus rotundus, Achyranthus aspera and Trianthema portulacastrum. Maximum weed control efficiency with F+IE 1125 g a.i. ha^-1 combined with 3% urea was 87% for C. rotundus, 75% for A. aspera in spring maize. It was 82% for C. rotundus and 90% for T. portulacastrum in autumn maize. The maize yield from F+IE 1125 g a.i. ha^-1 + 3% urea treated plots was 56% higher in spring and 68% higher in autumn than those from weedy check and was comparable to that of manual weeding. Maximum loss in grain yield due to unweeded check in spring and autumn maize was 44 and 41%, respectively.

Short title: Herbicide and urea combined for maize weed control

Keywords: Formasulfuron + Isoxadifen-Ethyl, Urea, Weeds, Maize, Grain yield