Kurtomathrips Morrilli: An Occasional Pest of Cotton on Texas South Plains

Kurtomathrips morrilli is a rare pest of cotton on the Southern High Plains of Texas. It was first documented damaging Texas cotton during the hot, dry conditions of 2011 in Gaines County. Little is known about  K. morrilli biology and its management in cotton. A field trial was initiated to evaluate insecticide efficacy against K. morrilli, and the effect of late season K. morrilli infestation on lint quality. Treatments included untreated check, spinetoram at 18.1 g a.i. per acre, imidacloprid at 27.7 g a.i. per acre, acephate at 81.6 g a.i. per acre, thiamethoxam at 27.2 g a.i. per acre, and acetamprid at 18.1 g a.i. per acre. Field trial was designed as an RCB with four replications. Thrips were counted by collecting 5 leaves per plot at 0, 7, and 14 days after treatment. Mean pre-treatment counts ranged from 15.4 to 88.26 thrips per plant. Thrips densities varied significantly across treatments at 7 and 14 DAT. Percent thrips control ranged from 74.6 percent in the imidacloprid treated plots to 94 percent in spineotoram treated plots.