Effect of Four Igr's Against the Potato Tuberworm, 1991

The response of potato tuberworm to ten doses of acyl-urea, diflubenzuron and triflumuron was evaluated in a series decreasing in halfs (e.g. 2,000, 1,000, 500 ppm, etc.). Potato tubers were submerged in the desired concentrations, put on paper to dry and then placed in one liter plastic containers. Over each tuber, 10 larvae were placed per replication, with four replicates/dose (40 larvae), and a total of 400 larvae per insecticide trial was used. A water-treated check was used. Larvae were obtained from Navidad, Nuevo Leon, Mexico and were maintained 30 d at 25 ± 2°C. Two samples at 10 and 15 d post-treatment were made to check mortality, and at 30 d for adult survival. The final analysis was based on adults because differences in mortality among stages was low. The mortality data were analyzed by probits to obtain LC50 and LC95 values for each insecticide.