Effects of prometryn applied in irrigation water on furrow irrigated cotton and residue persistence

Abstract

Field tests were conducted at two locations to determine the effects of prometryn (N,N’-bis(l-methylethyl)-6-(methylthio)-1,3,5- triazine-2,4-diamine] applied in the irrigation water on furrow irrigated cotton (Gossypium hirsutum LO. Application dates and rates were studied to determine their effects on cotton yield, cotton foliage response, weed control, and residue persistence. Prometryn in the Caporalᴿ 4L formulation was used in the study. The application of prometryn in the irrigation water did not significantly reduce cotton yields at either locations. There was no significant increase in prometryn symptoms in the cotton foliage due to the application of prometryn in the irrigation water. Significant control of Wrights groundcherry (Physalis wrightii Gray) was achieved at all growth stages, while control of woolly morningglory (Ipomea birsutula Jacq.f) was inconclusive. Soil residue persistence was determined by observing the effects on barley (Honieum vulgare L.) planted following the cotton. A significant amount of damage to the barley from prometryn residue was observed at one location while no damage occurred at the other location.