Cage Evaluation of Spray Applications on Cotton for Plantbug Control, 1993

Eight insecticide treatments were evaluated for efficacy against TPB at the Plant Science Research Farm, Mississippi State, MS. A RCBD with 4 replications was used. Plots were 35 ft long × 2 rows wide (38 inch spacing) separated by 12 untreated buffer rows. Foliar applications were applied 7 Jul at 9:45 a.m. with a high clearance spray tractor at 4 mph and 33 psi and 5 gpa. Temperature, relative humidity and wind speed were 91°F, 63% and 0.2 to 4.0 mph, respectively. Insects were collected the day prior to infestation by sweeping wild flowers (clover) with a sweep net, placing them in a glass enclosure, and collecting the adults with an aspirator. Adults were kept overnight in a glass container with a water wick and snap beans. Plants were infested on 7 Jul and 9 Jul by placing a cloth sleeve over the upper third of the plants, fastening them around the stem at the bottom with a rubber band containing two beads (Ponytail holder) placing 10 live insects on the plant and then closing the sleeve above the terminal with a second ‘ponytail holder’. Plants with cages were cut at 24h and returned to the laboratory where the cages were opened in a glass enclosure and the insects were evaluated for mortality. Those that could not move normally when prodded were considered dead. There were only enough insects for 3 replications for the 9 Jul infestation.