Submitted to: Western Society of Weed Science Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 12/1/2007
Publication Date: 7/21/2008
Citation: Boydston, R.A., Felix, J. 2008. Yellow Nutsedge control in Potato with Imazosulfuron. Western Society of Weed Science Meeting Proceedings. 61:6.
Technical Abstract: Yellow nutsedge control in potato with imazosulfuron was evaluated in trials conducted on a sandy loam soil near Pasco, WA and on a silt loam soil near Ontario, OR in 2007. Imazosulfuron was tested at 0.34, 0.45, and 0.56 kg ai/ha applied preemergence (PRE), PRE followed by postemergence (POST), and POST following standard treatments of s-metolachlor and rimsulfuron applied PRE in commercial fields naturally infested with yellow nutsedge. All POST applications included methylated oil at 1% V/V. Shepody potatoes were planted March 20, 2007 in 86 cm rows at the Pasco site and harvested July 9, 2007; while Russet Burbank potatoes were planted April 6, 2007 in 91 cm rows and harvested October 5, 2007 at the Ontario site. POST applications were applied 25 days after PRE applications when potatoes were 15 cm tall and yellow nutsedge had begun to emerge with some plants 10 cm tall. Yellow nutsedge control at the time of potato canopy closure tended to be greater with sequential applications of imazosulfuron applied PRE and POST than with single applications of imazosulfuron applied PRE. Sequential applications of imazosulfuron controlled yellow nutsedge 91 to 98% at Pasco and 79 to 90% at Ontario. No herbicide symptoms were evident on potato treated with imazosulfuron PRE or POST, but potato row closure was slightly delayed at the Pasco location with POST applied imazosulfuron treatments. At the Pasco location, herbicide treatments did not affect total or U.S. #1 potato yields, which averaged 26.8 and 23.4 ton/acre, respectively. At Ontario, all herbicide treatments increased total potato tuber yield compared to the nontreated control except the lowest rate of imazosulfuron 0.34 kg/ha applied PRE. U.S. #1 yields tended to be greatest with sequential herbicide treatments applied PRE and POST than with imazosulfuron applied only PRE. Imazosulfuron appears to be a promising tool for yellow nutsedge suppression in potato.