INTEGRATED WEED MANAGEMENT SYSTEMS FOR ORGANIC AND CONVENTIONAL CROPS OF THE SOUTHEASTERN COASTAL PLAIN
Location: Crop Protection and Management Research
Title: Peanut tolerance to pyroxasulfone
Submitted to: Peanut Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 1, 2011
Publication Date: December 1, 2012
Citation: Prostko, E., Grey, T., Webster, T.M., Kemerait, R. 2012. Peanut tolerance to pyroxasulfone. Peanut Science. 38:111-114.
Interpretive Summary: In 2010, peanut was planted on 522,000 ha in the U.S., while field corn, soybean, and wheat were planted on 36,000,000, 31,000,000, and 22,000,000 ha, respectively. Consequently, commercial research and development efforts for new herbicides are focused in these crops and not in peanut. Pyroxasulfone, formerly KIH-485, is a new broad-spectrum herbicide being developed for preemergence (PRE) use in field corn, soybean, and wheat. Pyroxasulfone is effective on many annual weed species including Palmer amaranth and Texas millet, two of the most common and troublesome weeds of peanut. Pyroxasulfone is an inhibitor of very-long-chain-fatty acids and should be categorized within the K3 group of herbicides, along with acetochlor, alachlor, dimethenamid-p, flufenacet, S-metolachlor, and propachlor. S-metolachlor is frequently used in peanut for the control of various weeds including yellow nutsedgeand Benghal dayflower. Limited information concerning the tolerance of legume crops, aside from soybean, to pyroxasulfone is available. Since research about the selectivity of pyroxasulfone in peanut is limited, the objective of these studies was to evaluate the tolerance of peanut to preemergence and postemergence applications of pyroxasulfone.
Due to limited hectares and production in comparison to field corn, soybean, and wheat, commercial research and development efforts by major manufacturers for potential new peanut herbicides are minimal. Field trials were conducted in Ty Ty and Plains Georgia in 2007 and 2008 to evaluate the tolerance of peanut to PRE and POST applications of pyroxasulfone at five rates (0, 120, 240, 360, and 480 g ai/ha). Pyroxasulfone did not cause significant peanut injury at the Ty Ty location. In Plains, PRE applications of pyroxasulfone caused significant crop stunting, particularly at the 360 and 480 g/ha rates. In Ty Ty, PRE applications of pyroxasulfone also resulted in greater expression of tomato spotted wilt virus than POST applications. Peanut yields were not reduced by any rate or timing of pyroxasulfone. These results suggest that pyroxasulfone may have some potential to be utilized in peanut.