Temperature and Host Plant Effects on Predatory Stink Bugs for Augmentative Biological Control

Abstract

Abstract Eggs of two predatory stink bugs, Podisus maculiventris (F.) and Perillus bioculatus (Say), hatched normally in cardboard capsules (“trichocaps”), but fewer nymphs came out of the capsules at 18°C compared with those kept at 25°C, and those that did come out took twice as long to do so at the cooler temperature. This may help explain inconsistent results in field trials using these predators to control Colorado potato beetles on potato in early spring. In greenhouse experiments testing the predators' consumption of Colorado potato beetle eggs on warm-weather solanaceous crops, neither predator species consumed any prey eggs on tomato plants, regardless of whether the nymphs were placed at the bases or at the tops of the plants. A field trial was conducted to determine whether a trap crop of potatoes could protect tomatoes from infestation with Colorado potato beetles, with predators augmentatively released in the trap crop to limit reproduction and subsequent movement back to the tomato crop. Few beetles migrated into the field in 1998, necessitating artificial infestation. Adult beetles moved from tomatoes to potato trap crops early in the season, but by mid-season potato foliage was less attractive due to potato leafhopper damage. Further work is needed to determine the effectiveness of this control method in the mid-Atlantic region.