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Halyomorpha halys(Stål) (Hemiptera: Pentatomidae) is an invasive pest which feeds on numerous economically significant crops. Many integrated pest management strategies for this species rely on effective season-long monitoring for H. halyspopulations, including attract-and-kill and threshold-based insecticide sprays. Previous studies have shown that a black pyramid trap effectively captures all mobile life stages of H. halys, however, these bulky, ground-deployed traps can be impractical in active orchard rows. Clear sticky cards have been used as a more practical tool for monitoring when paired with the H. halysaggregation pheromone and synergist. Here, the efficacy of deploying single- or double-sided sticky cards hanging in trees or deployed on wooden stakes was compared to standard black pyramid traps over 2 years. The efficacy of single-sided sticky cards deployed on wooden stakes was also evaluated after occlusion of 25%, 50%, or 75% of the surface area by 2D inert materials and 3D organic matter. Single-sided sticky cards were also exposed to simulated sunlight and rainfall for 0, 4, 8, and 12 wk before deployment on wooden stakes. Captures of H. halysadults using sticky cards deployed on wooden stakes were comparable to pyramid traps. Occlusion of cards by 25% or more of any material type led to a decrease in H. halyscaptures, however, weathering did not influence capture. These data show that clear sticky cards deployed on wooden stakes are effective for season-long monitoring of H. halysin apple orchards, and card replacement should be driven by maintenance of cleanliness.

Native apple maggot fly, Rhagoletis pomonella, and invasive spotted-wing drosophila, Drosophila suzukii, are key pests of apple and small fruit, respectively, in the United States. Both species are typically managed with standard insecticide applications. However, interest in alternative strategies that result in insecticide reductions has led to evaluations of nonnutritive sugars as toxicants for Drosophilaspecies and development of attracticidal spheres for both species. Here, we evaluated the survivorship of R. pomonellaand D. suzukiiwhen provided with standard diets that substituted saccharin, sucralose, aspartame, erythritol, dextrose, or mannitol for the sucrose component and compared them with standard diets and water-only controls for up to 15 days. Presence of erythritol and mannitol significantly decreased survivorship of R. pomonellaand erythritol significantly decreased the survivorship of D. suzukii.However, mobility trials following a 2 h exposure to aqueous solutions of each sugar treatment resulted in no strong impact on either species. Survivorship after 30 min exposure to erythritol or mannitol alone, or in combination with varying concentrations of sucrose (serving as a phagostimulant) at 30 min and 24 h were evaluated for both species. Only D. suzukiisurvivorship was affected with decreased survivorship on erythritol:sucrose solutions of 20:0% and 15:5% for 24 h. Based on all results, erythritol appeared most promising, and was integrated into attracticidal spheres as a toxicant but even at the highest concentration, survivorship remained unaffected for either species, thus making this nonnutritive sugar impractical and ineffective as a toxicant substitute in attracticidal spheres.

As Lycorma delicatula(White) continues to spread across the United States, more winegrapes are potentially susceptible to damage from this pest. Lycorma delicatula, spotted lanternfly, is primarily associated with Ailanthus altissima(Mill.) Swingle, a tree from its native range that is now globally distributed. While L. delicatulais a known pest of cultivated Vitisspp. in South Korea, its relationship with the specific grape species grown in the United States is unclear. This study assessed L. delicatulasurvivorship and development on 5 Vitisspecies, including 2 winegrape V. viniferaL. varieties, ‘Pinot Noir’ and ‘Chardonnay’, Concord grape, Vitis labruscaL., River grape, Vitis ripariaMichx., and muscadine grape, Vitis rotundifoliaMichx. var. ‘Carlos’. A diet of A. altissimaserved as a positive control. Lycorma delicatulaprovided with a diet of V. ripariaor V. vinifera‘Pinot Noir’ yielded the highest survivorship and fastest rates of development among grape diets and were statistically equivalent to those provided with A. altissima. Vitis rotundifoliadid not support L. delicatulagrowth past the third-instar life stage, indicating this species is a poor host for the early development of this pest. Our results indicate that both V. ripariaand V. viniferaare favorable hosts for L. delicatulaand may provide the means for this insect to invade and establish in new regions.

Lycorma delicatulaWhite, commonly called spotted lanternfly, is an invasive fulgorid that was first detected in the United States in Pennsylvania in 2014 and has spread across Eastern states. Lycorma delicatulais a phloem feeder, and feeding of persistent populations can cause wilt and dieback in host plants. Vineyards in infested regions have experienced vine loss, where damage has been attributed to L. delicatula. Nymphal and adult lifestages have been observed on cultivated apple and peach trees, but the feeding effects of this pest on these crops have not been quantified. Here, we caged young potted apple and peach trees and infested them with 50 nymphal or 25 adult L. delicatulaper plant for 3 months and tracked plant health. Horticultural measurements including trunk diameter, height, leaf drop, and photosynthesis rates were recorded before, during, and after the infestation. To evaluate the long-term effects of infestation, all apple and peach trees were removed from pots and planted in an orchard block where their phenology, growth, and physiology could be evaluated the following growing season. Short- and long-term measurements showed no significant differences in apple tree health between infested and noninfested trees. There was a significant reduction in the growth of trunk diameter in peach trees during exposure to early-instar nymphs; infested peach trees also had significantly increased frost damage to buds the following spring. However, there were no long-term impacts on peach growth and physiology. These results indicate that L. delicatulalikely will not be a major threat to these deciduous fruit crops.

Lycorma delicatulaWhite (Hemiptera: Fulgoridae) is an invasive phloem feeder with a broad host range that includes both hardwood trees and cultivated temperate fruit crops. Here, we evaluated acceptability of wild hosts, A. altissimaand Juglans nigraL. (Fagales: Juglandaceae) and cultivated hosts Vitis vinifera, Malus domestica(Rosales: Rosaceae), and Prunus persicaL. Batsch (Rosales: Rosaceae) to L. delicatulaunder field conditions. Fluorescent-marked early instar nymphs, late instar nymphs, or adult L. delicatulawere released at the base of single potted host plants and the number of individuals retained was recorded over 24 h. Paired choice trials with A. altissimaand another host plant were conducted. Individuals retained on or moving between plants were recorded over 24 h. Sentinel A. altissima, J. nigra, V. vinifera, M. domestica, and P. persicapotted plants were deployed at 5 sites and the number of L. delicatulapresent on each plant was recorded weekly. In single and paired host trials, early instars and adults were generally retained in higher numbers on A. altissimaand V. vinifera, and late instars were retained on A. altissimaand J. nigra. Significantly more L. delicatulawere present on sentinel A. altissimacompared with other host plants, except J. nigraduring the period when late instars were the most prevalent lifestage in the field. These results indicate that wild hosts such as A. altissimaand J. nigraare likely supporting establishment of L. delicatulapopulations, and that presence of cultivated V. viniferamay contribute to population establishment and growth.

The spotted lanternfly, Lycorma delicatula(White) (Hemiptera: Fulgoridae), is an invasive planthopper that was first detected in the United States in Berks County, PA, in 2014, and has since spread to 13 states in the Eastern United States. This phloem-feeding pest has a broad host range, including economically important crops such as grapevine, Vitisspp. Monitoring presence and relative abundance of L. delicatulais essential to develop pest management tools. Here, we compared deployment strategies to optimize use of L. delicatulamonitoring traps. Standard circle traps, sticky bands, and circle traps with replaceable bag tops were deployed at sites with either high or low populations present. Trap deployment at different heights and on different host tree species and trap sampling intervals were evaluated for standard circle traps only. Circle traps captured significantly more L. delicatulaadults at low-density sites compared with other trap types in 2021, and no differences were detected at high-density sights. Traps deployed 1 m from the ground captured significantly more adults than those deployed at 0.5 m; no differences were detected for nymphs. While no significant differences in captures were found among intervals, weekly or biweekly sampling prevented specimen degradation. Although traps deployed on Ailanthus altissima(Mill.) Swingle (Sapindales: Simaroubaceae) captured significantly or numerically more L. delicatulaat most sites, traps deployed on other hosts also yielded consistent captures. We were also able to alter the construction of circle trap skirts to allow for deployment on different sized tree trunks.

The invasive brown marmorated stink bug, Halyomorpha halys(Stål), is a pest of numerous economically important crops in the USA. In the Mid-Atlantic region, it is a significant, direct pest in tree fruit orchards, many of which are bordered by woodlots containing a variety of its deciduous tree and shrub hosts. During the growing season, H. halysmoves from woodland habitats into crops, but seasonal changes in its relative abundance between these adjacent habitats have not been examined. Using linear transects of six pheromone-baited pyramid traps that extended from 100 m into the interior of woodlots to 100 m into the interior of adjacent commercial apple orchards in Virginia, spatiotemporal changes in H. halyscaptures were measured during three growing seasons. Captures of H. halysadults and nymphs were recorded weekly from May through October, and annual data were separated into early, mid, and late-season captures. Only adults were captured during the early season, and there was no indication of a spatial trend in captures across traps in the transects among years. Beginning in mid-season and becoming increasingly apparent by late season, captures of H. halysadults and nymphs tended to become most frequent in traps at the woods and orchard edges and at 50 m into the orchard interior. These findings conform with and expand upon previous research documenting an edge effect for H. halysrelative abundance and can inform and support the optimization of perimeter-based management strategies for H. halysin Mid-Atlantic apple orchards.

Brown marmorated stink bug, Halyomorpha halys, is native to Asia and has invaded North America and Europe inflicting serious agricultural damage to specialty and row crops. Tools to monitor the spread of H. halysinclude traps baited with the two-component aggregation pheromone (PHER), (3S,6S,7R,10S)-10,11-epoxy-1-bisabolen-3-ol and (3R,6S,7R,10S)-10,11-epoxy-1-bisabolen-3-ol, and pheromone synergist, methyl (2E,4E,6Z)-decatrienoate (MDT). Here, an international team of researchers conducted trials aimed at evaluating prototype commercial lures for H. halysto establish relative attractiveness of: 1) low and high loading rates of PHER and MDT for monitoring tools and attract and kill tactics; 2) polyethylene lure delivery substrates; and 3) the inclusion of ethyl (2E,4E,6Z)-decatrieonate (EDT), a compound that enhances captures when combined with PHER in lures. In general, PHER loading rate had a greater impact on overall trap captures compared with loading of MDT, but reductions in PHER loading and accompanying lower trap captures could be offset by increasing loading of MDT. As MDT is less expensive to produce, these findings enable reduced production costs. Traps baited with lures containing PHER and EDT resulted in numerically increased captures when EDT was loaded at a high rate, but captures were not significantly greater than those traps baited with lures containing standard PHER and MDT. Experimental polyethylene vial dispensers did not outperform standard lure dispensers; trap captures were significantly lower in most cases. Ultimately, these results will enable refinement of commercially available lures for H. halysto balance attraction and sensitivity with production cost.

The objectives of this study were to quantify the virulence of four entomopathogenic fungal species to pupae of Rhagoletis pomonella(Walsh) (Diptera: Tephritidae) and to determine the potential to combine entomopathogenic fungi (EPFs) and entomopathogenic nematodes (EPNs) for biological control of this pest. The four species of EPFs included Beauveria bassiana(strain GHA), Metarhizium brunneum(strain F52), Isaria javanica(wf GA17), and Isaria fumosorosea(Apopka 97 strain). In laboratory assays, all fungi reduced adult emergence but there were no differences between fungal species. Isaria javanicaand M. brunneumwere examined further in a EPFs and EPNs bioassay that also included the EPNs Steinernema carpocapsae(ALL strain) and S. riobrave(355 strain). All nematodes and fungi were applied either alone or in combination (fungus + nematode). There were no differences between species within the same entomopathogen group (fungi and nematodes). However, the treatment with S. riobraveresulted in lower R. pomonellaemergence than either fungal species. The combination of S. riobraveand I. javanicaresulted in the lowest R. pomonellaemergence (3%) at fourth-week interval, which was significantly lower than any of the single-agent applications, yet virulence of the other three combination treatments was not different from their respective nematode treatments applied alone. Additive interactions were detected for all fungus–nematode combinations. This study suggests that application of entomopathogenic nematodes and fungi could be an effective option to suppress R. pomonellapopulations.

Since the initial detection of the invasive Halyomorpha halys(Stål) in the United States in the late 1990s, this insect has emerged as a severe agricultural and nuisance pest. Nuisance problems are due to adult dispersal to overwintering sites in the fall at which time they alight onto and eventually settle within human-made structures in addition to natural harborage. This study examined how three factors, elevation, light, and moisture affected overwintering site selection by H. halysin the mid-Atlantic. Observational counts performed along elevational transects revealed elevation was significant predictor of H. halysabundance during both years of the study in 2014 and 2015 with more adults observed at higher elevations. Choice tests examining effects of moisture and light on settling behavior demonstrated H. halyssettled within overwintering shelter boxes in significantly greater numbers when shelters were dry compared with those having moist conditions, and in darkened shelters compared with those augmented with LED lights. Our findings indicate that H. halysuse cues at both landscape and very localized levels when seeking and selecting overwintering sites.

The apple maggot, Rhagoletis pomonella(Walsh) (Diptera: Tephritidae), is considered a key pest of apples and is native to the eastern United States. The virulence of seven different species of entomopathogenic nematodes (EPN) was assessed against pupae of R. pomonellaunder laboratory conditions. Nematode species and strains included Steinernema carpocapsae(ALL strain), Steinernema feltiae(SN strain), Steinernema riobrave(355 strain), Steinernema glaseri(VS strain), Heterorhabditis bacteriophora(VS strain), Heterorhabditis indica(HOM1 strain), and Heterorhabditis megidis(UK211 strain). We conducted three bioassays: (i) short-term exposure cup bioassay (7 d), (ii) long-term cup bioassay (30 d), and (iii) pot bioassay (30 d). In the short-term exposure bioassay, all nematode strains (applied at 54 infective juvenile nematodes (IJs) cm−2) significantly reduced (range: 42.9-73.8%) insect survival relative to the control, but no differences were observed among the treatments. For the long-term exposure bioassay, using the same EPN application rate as the short exposure assay, all treatments reduced adult R. pomonellaemergence compared with the control. Steinernema riobravewas the most virulent (28.3% survival), and S. glaseriand H. megidiswere the least virulent (53.3% survival). In the pot experiment, S. riobraveand S. carpocapsae(applied at 27 IJs cm−2) had the highest virulence (23.3 and 31.7% survival of R. pomonella, respectively), while H. bacteriophorawas the least effective (68.33% survival). Our results indicate that S. riobrave, S. carpocapsae, and S. feltiaehave substantial potential to attack R. pomonellapupae, and their field application under the tree canopy (prior to adult emergence) in the spring when temperatures are conducive might be a good option for successful IPM of apple maggot fly.