P. Cockerelli Control by Seed Piece Treatment with Systemic Insecticide, 1975

Seed potatoes of the selected varieties were cut and treated on February 26. Treatment was accomplished by putting the dust and seed potatoes into a plastic drum fitted with baffles and the drum mechanically revolved for approximately 3 min. Seed pieces were planted on February 27 in Laveen clay loam with a 2-row experimental precision potato planter. Plots were two 34-inch beds wide and 30 feet long. The treatments we.re replicated 3 times in a randomized block design. Stand counts were made in each plot by counting all emerged plants in both beds. Psyllid counts were made at weekly intervals beginning April 23 thru June 4. Twenty-five randomly selected complete leaves were gathered from each plot and the psyllid nymphs and adults were counted. Ayerage daytime temperatures during the growing season were March 71°, April 74°, May 90° and June (first 10 days) 101°F. Plots were harvested June 10 with a single row potato digger. They were then graded according to U. S. standards and grades.