Effects of Aggregation Lure and Tree Species on Halyomorpha halys (Hemiptera: Pentatomidae) Seasonal Oviposition

Abstract

The brown marmorated stink bug, Halyomorpha halys (Stål), is a polyphagous pest that feeds on a wide variety of agricultural commodities including tree fruits, berries, vegetables, field crops, and ornamental trees and shrubs. Accurate knowledge of where H. halys lays eggs is critical to optimize the potential release of Trissolcus japonicus (Ashmead), a scelionid egg parasitoid native to the same host region as H. halys. Ideally, parasitoids should be released in and around areas with high host density. In southwestern Virginia in 2017 and 2018, we searched trees for egg masses in an urban environment and nonmanaged wooded border environment. We also evaluated the effects of a commercial aggregation lure on the number of eggs being deposited. This aggregation lure, when combined with methyl (E,E,Z)-2,4,6-decatrienoate (MDT), has been shown to attract both adult and nymph H. halys and its effects on egg laying were not known. Results of this study showed no difference between the number of eggs laid on trees with and without lures. Catalpa trees, Catalpa bignonioides Walter, had the most egg masses throughout the course of the study; however, the redbud, Cercis canadensis L., had similar numbers in the late July and August. There was an overall trend with more eggs masses found on trees with fruiting structures present. This information can provide insight on where and when to make augmentative releases of egg parasitoids for H. halys.

Seasonal Captures of Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae) and the Effects of Habitat Type and Tree Species on Detection Frequency

“…Rather, T. japonicus foraging may be most strongly associated with the presence or density of H. halys and its egg masses. Counts of H. halys egg masses on ornamental trees in an urban landscape by Formella et al [ 43 ] revealed no significant differences among hosts in egg mass numbers, confirming H. halys oviposition on many plant species. However, their ground-based counts via visual observations may have underestimated egg mass density, based on data [ 20 ] showing greater numbers of H. halys egg masses producing T. japonicus from those collected at mid-canopy compared with other tree strata.…”

First Insights on Early Host Plants and Dispersal Behavior of Halyomorpha halys (Hemiptera: Pentatomidae) from Overwintering to Crop Colonization

“…Before crop colonization, some wild hosts are suitable not only for nutrition but also for reproduction [6,15]. For H. halys oviposition, the presence of fruiting structures seems to contribute to plant selection more than aggregation pheromone lures [32]. In June, nymphs were found only on a few plants, such as peach, ivy, walnut, red mulberry, wheat, black locust, false indigo-bush, European spindletree, common dogwood, maple, and hazelnut.…”

Influence of Trap Location in the Tree Canopy on Captures of Adventive Trissolcus japonicus (Hymenoptera: Scelionidae)

“…Although Quinn et al (2019b) reported that H. halys egg masses and egg masses parasitized by T. japonicus were most abundant in the midcanopy of felled A. altissima, other studies using visual surveys from the ground have reported H. halys egg masses that were presumably in the lower portion of tree canopies (Bakken et al 2015, Formella et al 2020. Given that female T. japonicus use host-associated olfactory cues for host location, recognition, and acceptance (Zhong et al 2017, Boyle et al 2020, Malek et al 2021, results from the present study suggest that it forages throughout the canopy, or at least is attracted to the visual cue from YSC from various locations in the canopy.…”