Effect of Planting Date on Response of Imidazolinone-tolerant Wheat to Imazamox and Other Herbices

Abstract

The objective of this research was to determine the effect of planting date on the response of imidazolinone tolerant wheat to imazamox and other herbicides. Field experiments were conducted during the 2003 and 2004 winter wheat growing seasons. Planting dates were between October 1 and December 22. Treatments included chlorsulfuron + metsulfuron-methyl, imazamox, mesosulfuron-methyl, propoxycarbazone-sodium, sulfosulfuron, and triasulfuron. Crop injury was visually estimated. Data statistically analyzed included moisture content, dockage, wheat volume weight, and grain yield. Visual crop injury was not observed. Wheat grain yield declined with later planting date. At the 2003 Perkins site, all herbicide treatments except imazamox reduced wheat grain yield. Chlorsulfuron + metsulfuron-methyl (5:1), imazamox, propoxycarbazone-sodium, and sulfosulfuron reduced grain yield when applied to wheat planted on November 11. Mesosulfuron-methyl was the only herbicide that didn't reduced grain yields when applied to wheat planted on December 1.