Monday, December 11, 2006

Texas sorghum producers' perceptions of sorghum midge (Diptera: Cecidomyiidae)

Tebkew D. Belete, and Bonnie B. Pendleton, West Texas A&M University, Division of Agriculture, Canyon, TX

Experience, source, and availability of information on insect pests and their control influence farmersí perceptions of an insect as a pest and affect decisions on control tactics to use and adoption of new control methods. Texas sorghum producersí perceptions were surveyed of sorghum midge, Stenodiplosis sorghicola (Coquillet), a worldwide key insect pest of sorghum, Sorghum bicolor (L.) Moench. A two-page questionnaire was prepared and mailed on 26 January 2006 to 197 members of the Texas Grain Sorghum Association. A total of 91 responses was obtained, but 17.6% of the respondents did not grow sorghum and were excluded from the study. Averages of 54.1, 2.8, and 29.2% of the respondents believed sorghum midge was an important pest of dryland, irrigated, and both dryland and irrigated sorghum, respectively. The rest (13.9%) indicated sorghum midge was not a problem. Estimates of annual yield loss attributable to sorghum midge ranged from zero to more than 40%. An average of 97.1% of the respondents scouted their sorghum for sorghum midge at least once during flowering, and 2.9% of respondents did not scout sorghum. It was found that 40.4, 24.1, and 3.6% of the respondents applied insecticide one, two, and three(s) times, respectively, per season. The rest (31.9%) did not apply insecticide. Knowledge about sorghum midge-resistant hybrids also differed - only 4.1% of respondents use or have used a sorghum midge-resistant hybrid, 67.8% knew they grow susceptible hybrids, and the rest (28.1%) did not know whether the hybrid they grow was resistant or susceptible.

Species 1: Diptera Cecidomyiidae Stenodiplosis sorghicola (sorghum midge)