With the help of Ty Torrance, we completed a bioassay on flea beetles on eggplant this week. This pest has become more difficult to control in recent years, with Torac previously identified as our best option for control. This bioassay was conducted to evaluate a few selected products and one experimental product that is hopefully near registration.
Each product was mixed up at the indicated rate as if we were spraying 100 gpa. This rate and one half of this rate were tested. Leaves collected from the field were dipped into the solution, allowed to dry, and placed into a petri dish with a moist paper towel. The petri dish was then sealed with parafilm and 10 field collected adult beetles were introduced. Mortality was checked at 72 hours after the test was established.
Treatments and rates were: Torac at 21 fl oz/ac, Assail at 2.5 oz/ac, Avaunt at 6 oz/ac, Experimental product and a non-treated control (Check). All insecticides were mixed with Dyne-Amic at 0.25% to insure even coverage of the leaf.
Of the currently registered products evaluated, Torac provided the highest mortality while Avaunt provided the highest overall morbidity+mortality. Those insects rated as morbid would likely not survive in the field, but were alive at the 72 hour evaluation. Assail provided no control of this pest. The Experimental product provided the best overall control.