Weed Management in North Carolina Peanuts (Arachis Hypogaea) withS-metolachlor, Diclosulam, Flumioxazin, and Sulfentrazone Systems

Abstract

Experiments were conducted at the Upper Coastal Plain Research Station near Rocky Mount and at the Peanut Belt Research Station near Lewiston-Woodville in 2002 and 2003. Peanut injury was minimal (< 5%) with all soil-applied programs. S-Metolachlor PRE alone or in mixture with sulfentrazone, diclosulam, or flumioxazin controlled annual grasses similarly (66 to 87%). The addition of imazapic plus 2,4-DB POST increased annual grass control (> 93%). Sulfentrazone or diclosulam in mixture with S-metolachlor were the best PRE options, with 94% and 92% control of yellow and purple nutsedge, respectively, with flumioxazin being least effective at 70%. Diclosulam and flumioxazin in mixture with S-metolachlor were the best PRE options, with 99% and 93%, respectively for common ragweed control, whereas sulfentrazone was the least effective at 65%. S-Metolachlor in mixture with sulfentrazone, diclosulam, or flumioxazin PRE were similar (87 to 90%) for common lambsquarters control. S-Metolachlor in mixture with sulfentrazone, diclosulam, or flumioxazin provided similar levels of entireleaf, ivyleaf, pitted, and tall morningglory control (87, 86, and 87%, respectively) and better than S-metolachlor alone at 64%. Flumioxazin in mixture with S-metolachlor was the best PRE option for control of Palmer amaranth at 96%, whereas diclosulam with S-metolachlor was the best PRE option for control of eclipta at 100%. The prepackaged mixture of acifluorfen and bentazon plus 2,4-DB POST and imazapic plus 2,4-DB POST were similar for all morningglory species (> 96%) and Palmer amaranth control (93 and 97%, respectively). Peanut treated with S-metolachlor plus diclosulam PRE numerically yielded the highest at 3,210 kg/ha, but were statistically equivalent to S-metolachlor plus flumioxazin PRE at 3,040 kg/ha. Peanut treated with imazapic plus 2,4-DB POST yielded the most at 3,400 kg/ha, while peanut treated with a prepackaged mixture of acifluorfen and bentazon plus 2,4-DB POST yielded less (3,070 kg/ha).Nomenclature: 2,4-DB, acifluorfen, bentazon, diclosulam, flumioxazin, imazapic, S-metolachlor, sulfentrazone, common lambsquarters, Chenopodium album L. CHEAL, common ragweed, Ambrosia artemisiifolia L. AMBEL, eclipta, Eclipta prostrata L. ECLAL, entireleaf morningglory, Ipomoea hederacea var. integriuscula Gray IPOHG, ivyleaf morningglory, Ipomoea hederacea (L.) Jacq. IPOHE, Palmer amaranth, Amaranthus palmeri S. Wats. AMAPA, pitted morningglory, Ipomoea lacunosa L. IPOLA, purple nutsedge, Cyperus rotundus L. CYPRO, tall morningglory, Ipomoea purpurea (L.) Roth PHBPU, yellow nutsedge, Cyperus esculentus L. CYPES, peanut, Arachis hypogaea L., ‘NCV-11’, ‘VA-98R’