Field Evaluation of Advanced Breeding Lines for Organic Cotton Production

Over 90% of cotton produced in the U.S. is grown with genetically-modified (GM) seed.  However, use of GM seed for certified organic production is forbidden by organic certification guidelines.  There is a distinct need for high-performing, non-GM cotton varieties for growers interested in pursuing organic production.  With 95% of the organic cotton in the U.S. grown on the Texas High Plains (THP), there is also need for varieties developed specifically for production in that region.  Thrips (Thysanoptera: Thripidae) have been identified as a major early-season pest by organic growers on the THP.  Therefore, developing non-GM cultivars with high tolerance or resistance to thrips injury is paramount for providing viable options to growers and improving overall production.  Two field trials were conducted in Lubbock, TX and Meadow, TX (under organic production) in 2011 to evaluate thrips resistance potential and agronomic performance of 8 advanced cotton breeding lines and one commercial check cultivar.  The trials were planted in a randomized complete block design with 4 replications.  Thrips injury was assessed for each genotype in Meadow by measuring leaf surface area weekly 4 times, ending the 5^th week after emergence.  Yield and fiber quality data were also collected to evaluate the overall agronomic performance of each line.  Results will help to identify parent lines to use in a breeding program for developing cultivars for organic cotton production.