Predation of Anasa tristis (Hemiptera: Coreidae) by Geocoris punctipes (Hemiptera: Geocoridae)
2019
Fair, C.G. | Braman, S.K.
Thesquash bug, Anasa tristis (DeGeer), is an indigenous pest of squash, Cucurbita pepo L., and other cucurbits. Geocoris punctipes (Say) adults were collected from stands of mixed grasses in Spalding County, GA, held without food for 24 h, and presented A. tristis eggs, first instars, or second instars in no-choice tests. Consumption of first and second instars was significantly greater by females than by males. Egg consumption was very low with no difference between males and females (P > 0.05). Male G. punctipes consumed a range of 0 to 3 first-instar squash bugs, 0 to 6 second-instar squash bugs, and 0 eggs during the 72-h exposure. Females consumed a range of 0 to 10 first-instar squash bugs, 0 to 10 second-instar squash bugs, and a range of 0 to 1 eggs. Male G. punctipes consumed on average 1.08 ± 0.24 first-instar squash bugs, 1.68 ± 0.41 second-instar squash bugs, and 0 eggs during the 72-h exposure. Females consumed on average 4.12 ± 0.56 first-instar squash bugs, 4.28 ± 0.56 second-instar squash bugs, and 0.12 ± 0.06 eggs. Background mortality for first and second instars was similar and exceeded that for eggs in control, male, and female trials. Previous research demonstrated seasonal overlap in squash bug nymphs and G. punctipes occurrence. These data suggest that G. punctipes can contribute to the suppression of early-season squash bug populations.
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