Control on Fall Squash, 1987:

A pesticide efficacy trial was conducted at the University of Arizona Valley Experiment Station in Yuma to evaluate the ability of various insecticides to control the sweetpotato whitefly on squash. Plots were planted 25 Sept. Experimental materials were compared with untreated control plots and Thiodan 3 EC. A completely randomized design was used with 4 plots receiving each treatment. Plots measuring 6 by 2 m were separated by 22.25 m along the rows and 33.3 m across the rows. Test materials were applied 27 Oct using a CO2-pressurized backpack sprayer at a pressure of 206.8 kPa and a rate of 83.3 liter/hectare. Three sampling methods were used to record the number of adult whiteflies: In the leaf counts 10 leaves from each plot were examined; in vacuum samples, whiteflies were collected using a hand vacuum for a period of 5 s/plot; sticky card trap was placed in each plot from 10 am to 11 am. The leaf count sampling was the only method to show separation between the treatment means, so these are the only data presented here.