Identifying Accessions and Management Practices for the Production of Pima Cotton in South Carolina

Currently in the US, Pima Cotton (Gossypium barbadense L.) is only grown out west in California, Arizona, New Mexico, and Texas. Pima cotton accounts for 3% of the total cotton production in the US, with the other 97% being Upland cotton (Gossypium hirsutum L.). Pima has superior fiber quality with longer, stronger, finer, and more uniform fibers than upland, making the fibers easier to process and spin into thread. Due to these high quality fiber properties, Pima is currently valued at more than twice the price of Upland per pound. In order to expand the production of Pima cotton into the Southeastern cotton belt, identification of specific varieties/accessions with acceptable yield, fiber quality, and adaptation to South Carolina’s growing conditions are needed. Management practices such as irrigation and planting date are also important factors to consider for cultivating Pima cotton in South Carolina, as Pima generally has a longer growing season than Upland by about three to four weeks, and is regularly irrigated out west. In this study, there are two separate 2-year field trials that took place in 2018 and 2019 at the Pee Dee REC in Florence, SC. In the first trial, 44 Pima accessions, four commercial Pima varieties, and two Upland checks are being evaluated for their yield, yield performance, and fiber quality. In the second trial, three commercial Pima varieties, one Pima accession, and one Upland check were grown under irrigated or dryland conditions, and under three different planting dates, Late-April, Mid-May, and Late-May.  In this trial the yield, yield performance, and fiber quality are being compared between varieties, planting dates, and irrigation type. Varieties/accessions identified in these trials are currently being used in a breeding study at the Pee Dee REC in Florence, SC.