Postemergence Weed Control Systems Without Dinoseb for Peanuts (Arachis hypogaea)

Postemergence treatments utilizing various combinations of fluazifop-P, paraquat, and 2,4-DB were compared to a preplant-incorporated (PPI) application of benefin followed by a ground-cracking application of alachlor and dinoseb plus naptalam and a postemergence application of 2,4-DB for weed control, peanut yield, and net economic return to land, overhead, and management. The greatest peanut yields (3-yr average of 4510 kg/ha) and net returns (3-yr average of $521/ha) were provided by a postemergence system that utilized one ground-cracking and one postemergence application of paraquat and one postemergence application of fluazifop-P and 2,4-DB. Seven postemergence systems provided equivalent or greater yield and net returns than the PPI and dinoseb plus naptalam system. Fresh weight reductions of Texas panicum, sicklepod, Florida beggarweed, and pitted morningglory from postemergence weed control systems were equivalent to reductions obtained from the PPI and dinoseb plus naptalam system. The addition of paraquat and 2,4-DB to the PPI and dinoseb plus naptalam system improved the 3-yr average peanut yield and net economic return by 510 kg/ha and $136/ha, respectively, compared to the same system without paraquat and 2,4-DB.