Defoliation Research on Pima and Upland Cotton at the Maricopa Agricultural Center in 1993

Abstract

Field studies were conducted at the Maricopa Agricultural Center to evaluate the effectiveness of selected defoliation treatments on Pima and upland cotton under warm and cool weather conditions. Weather conditions during September tests were warm and dry while in late October tests weather was very cool. Defoliation treatments resulted in a high percentage of leaf desiccation in a test on 10 September. Ginstar and Dropp + Def treatments gave good defoliation of cotton in a 23 September test. In October tests, defoliation treatments were effective on Pima cotton but upland cotton as difficult to defoliate. Ginstar defoliant was generally as effective as the Dropp + Def treatment at the rates tested.