Parasitism and predation of sentinel eggs of the invasive brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), in the southeastern US

Abstract

The invasive brown marmorated stink bug, Halyomorpha halys, is present in the Piedmont and expanding into the Coastal Plains Regions of the southeastern US. Consequently, this study was conducted to evaluate parasitism and predation of H. halys sentinel egg masses by native parasitoids and predators in woodland habitats and orchard, vineyard, row, and vegetable crops alongside these habitats in Alabama and Georgia in 2017 and 2018. Ten primary parasitoid species, including two new records, and one hyperparasitoid emerged from eggs. Trissolcus japonicus was not detected. Ooencyrtus sp. was the prevalent parasitoid species in vegetables while Telenomus podisi was the predominant species in row crops. Anastatus reduvii, An. mirabilis, Tr. brochymenae, and Tr. euschisti were the prevalent species in woodland and orchard habitats. Trissolcus edessae Fouts occurred primarily in orchards. Trissolcus basalis and Gyron obesum were observed in vegetable habitats. Percentage successful development to adults, sex ratio, and percentage of parasitism per egg mass was highest for Tr. edessae. Predation damage included complete and incomplete chewing, stylet sucking, puncture sucking, and removal of whole eggs from egg masses. Hole and non-stylet sucking damage were discovered. Chewing and piercing-sucking predation constituted the majority of predation in woodlands, plum, blueberry, tomato, pecan, peach, and okra. Mainly chewing predation and egg removal occurred in soybean, cotton, and strawberry. Piercing-sucking predation was common in wine grape and apple. There was no difference between fresh and frozen eggs in the proportion of parasitism and predation both years. In 2017, overall percent parasitism was higher for blueberry compared to other crops except peach and apple. No differences were detected in 2018. Peak parasitism (72.3%) in apple at a site in 2017 represented the highest parasitism rate. Predation was highest in soybean and cotton. Indeed, predation in soybean reached very high levels in 2017 (96.3%) and 2018 (90.3%). In conclusion, native natural enemies parasitize and prey on H. halys egg masses in the southeastern US.