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Brown stink bug, Euschistus servus (Say),and green stink bug, Acrostenzum hilare (Say) (Hemiptera: Pentatomidae), are major agricultural pests. Although various insecticides are used to control nymphs and adults, little is known about how they affect eggs. Laboratory bioassays and field trials were conducted to determine the efficacy of common field rates of acephate, A-cyhalothrin, spinosad, and thiamethoxam on developing E. servus and A. hilare eggs, as well as Telenornus podisi Ashmead (Hymenoptera: Scelionidae) parasitoids developing in E. servus eggs. In laboratory bioassays, egg masses were dipped into insecticide and water solutions and assessed for mortality after 2 wk. In the field trials, egg masses on a cloth section were pinned to leaves in each plot of a randomized complete Hock and returned to the laboratory 24 h after exposure to insecticide sprays. Mortality was assessed after 2 wk. In dip bioassays, there was a significant effect of insecticide treatment on A. hi/are eggs with all insecticides resulting in greater mortality than the water control. However, no effect of treatment occurred in the field with A. hilare or for E. servus eggs in both the laboratory bioassays and the field trials. In contrast, developing T. podisi parasitoids showed significant mortality when exposed to all insecticide treatments, when dipped or field-treated. Spinosad and A-cyhalothrin treatments resulted in 100% mortality of T. podisi, and acephate resulted in greater mortality than thiamethoxam. Our results suggest that there is relatively little efficacy from insecticide sprays on stink bugs developing in eggs but that mortality of egg parasitoids may be significant. [ABSTRACT FROM AUTHOR]

Microbes and enzymes play essential roles in soil and plant rhizosphere ecosystem functioning. However, fungicides and plant root secretions may impact the diversity and abundance of microbiota structure and enzymatic activities in the plant rhizosphere. In this study, we analyzed soil samples from the rhizosphere of four cannabinoid-rich hemp ( Cannabis sativa ) cultivars (Otto II, BaOx, Cherry Citrus, and Wife) subjected to three different treatments (natural infection, fungal inoculation, and fungicide treatment). DNA was extracted from the soil samples, 16S rDNA was sequenced, and data were analyzed for diversity and abundance among different fungicide treatments and hemp cultivars. Fungicide treatment significantly impacted the diversity and abundance of the hemp rhizosphere microbiota structure, and it substantially increased the abundance of the phyla Archaea and Rokubacteria. However, the abundances of the phyla Pseudomonadota and Gemmatimonadetes were substantially decreased in treatments with fungicides compared to those without fungicides in the four hemp cultivars. In addition, the diversity and abundance of the rhizosphere microbiota structure were influenced by hemp cultivars. The influence of Cherry Citrus on the diversity and abundance of the hemp rhizosphere microbiota structure was less compared to the other three hemp cultivars (Otto II, BaOx, and Wife). Moreover, fungicide treatment affected enzymatic activities in the hemp rhizosphere. The application of fungicides significantly decreased enzyme abundance in the rhizosphere of all four hemp cultivars. Enzymes such as dehydrogenase, dioxygenase, hydrolase, transferase, oxidase, carboxylase, and peptidase significantly decreased in all the four hemp rhizosphere treated with fungicides compared to those not treated. These enzymes may be involved in the function of metabolizing organic matter and degrading xenobiotics. The ecological significance of these findings lies in the recognition that fungicides impact enzymes, microbiota structure, and the overall ecosystem within the hemp rhizosphere.

Lycorma delicatula , White (Hemiptera: Fulgoridae), spotted lanternfly, is a univoltine, phloem-feeding, polyphagous and invasive insect in the USA. Although a primary host for this species is Ailanthus altissima , tree of heaven, L. delicatula also feeds on a wide range of hosts important to the USA including cultivated grapevines. Due to the need for classical or augmentative biological control programs to reduce impacts of L. delicatula across invaded areas, we developed a laboratory-based rearing protocol for this invasive species. Here, we evaluated the use of A. altissima apical meristems, epicormic shoots, and fresh foliage cut from A. altissima as a food source for rearing newly hatched L. delicatula . On these sources of plant material <20% of L. delicatula developed into adults and no oviposition occurred. However, when young, potted A. altissima trees were used as a food source, >50% of L. delicatula nymphs developed to the adult stage under natural daylengths and temperatures ranging from 20-25°C. The addition of wild grapevine, Vitis riparia , did not increase survivorship or reduce development time. To elicit mating and oviposition, adults were provided with A. altissima logs as an oviposition substrate and maintained under shortened daylengths and reduced nighttime temperatures (12L:12D and 24°C:13°C). This resulted in 2.12 egg masses deposited per female, which was 4× more than when adults were maintained in standard rearing conditions (16L:8D and 25°C). Based on these experiments, we present a protocol for reliably rearing L. delicatula under laboratory and/or greenhouse conditions., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Nixon, Jones, Dechaine, Ludwick, Hickin, Sullivan, Elsensohn, Gould, Keena, Kuhar, Pfeiffer and Leskey.)

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. halys include 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. halys to 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. halys to balance attraction and sensitivity with production cost., (© The Author(s) 2021. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Flea beetles, are common pests of cabbage Brassica oleracea L. (Brassicales: Brassicaceae) and eggplant Solanum melongena L. (Solanales: Solanaceae), but little is known about the flea beetle populations in Virginia, their impact on yield, or the most effective control methods. This research investigates flea beetle populations and the impact of their feeding injury on cabbage and eggplant in Southwest Virginia and determines the most efficacious control methods. In Whitethorne, VA, cabbage and eggplant crops were vacuum sampled weekly throughout two summers (2015, 2016). Crucifer flea beetle, Phyllotreta cruciferae (Goeze) (Coleoptera: Chrysomelidae), and striped flea beetle, Phyllotreta striolata Fabr. (Coleoptera: Chrysomelidae) were found on cabbage; whereas, eggplant flea beetle, Epitrix fucula (Crotch) (Coleoptera: Chrysomelidae), and the tobacco flea beetle, Epitrix hirtipennis (Melsheimer) (Coleoptera: Chrysomelidae) were found on eggplant. To evaluate the impact of flea beetle feeding on these plants flea beetle densities and defoliation were assessed weekly and individual plant, as well as whole plot yields, assessed at harvest. For cabbage, significant yield reductions were observed between 1 and 20% and >60% defoliation. Similarly, significant yield reductions were observed between 41 and 60% and >60% defoliation for eggplant. The efficacy of various insecticides was also evaluated. Soil application of the systemic neonicotinoid dinotefuran, imidacloprid, and the foliar-applied bifenthrin resulted in the fewest beetles, the least amount of leaf defoliation, and the highest yield in cabbage and eggplant. This research helps vegetable growers to better understand the severity of these pests and how to effectively combat them., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Cereal leaf beetle, Oulema melanopus L., is a pest of small grains and the literature conflicts on whether it is more abundant in sparse or dense stands of wheat. Our objectives were to determine the impact of stand denseness on cereal leaf beetle abundance and to investigate the regional dispersion of cereal leaf beetles across North Carolina and Virginia. One-hundred twenty fields were sampled across North Carolina and Virginia during 2011 for stand denseness, and cereal leaf beetle eggs, larvae, and adults. Two small-plot wheat experiments were planted in North Carolina using a low and a high seeding rate. Main plots were split, with one receiving a single nitrogen application and one receiving two. Egg density, but not larva or adult density, was positively correlated with stand denseness in the regional survey. Furthermore, regional spatial patterns of aggregation were noted for both stand denseness and egg number. In the small-plot experiments, seeding rate influenced stand denseness, but not nitrogen application. In one experiment, egg densities per unit area were higher in denser wheat, while in the other experiment, egg densities per tiller were lower in denser wheat. Larvae were not influenced by any factor. Overall, there were more cereal leaf beetle eggs in denser wheat stands. Previous observations that sparse stands of wheat are more prone to cereal leaf beetle infestation can be attributed to the fact that sparser stands have fewer tillers, which increases the cereal leaf beetle to tiller ratio compared with denser stands., (© The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The brown marmorated stink bug, Halyomorpha halys (Stål), is native to eastern Asia and is presently invading North America. Little is known about the exposure to and effects of winter temperatures in newly invaded regions on H. halys The overwintering habitats that this species utilizes vary greatly in their thermal buffering capacity. They naturally overwinter in aggregations beneath loose bark on trees and in cliff outcroppings, but will also commonly aggregate in buildings. Effects of cold temperatures such as mortality and freezing have yet to be quantified in the invading population. We report that H. halys is chill intolerant (i.e., dies before reaching its freezing point), and that the degree of cold tolerance of populations in North America differs by season, sex, and acclimation location. The mean winter supercooling point (± SEM) of individuals acclimated in Minnesota was -17.06 °C ± 0.13 and in Virginia was -13.90 °C ± 0.09. By using laboratory assays of lower lethal temperatures and ambient air temperature records, we accurately forecasted mortality for field experiments in Minnesota and Virginia. Temperature refugia provided by human-built structures are likely crucial for overwintering survival during atypically cold winters and possibly contribute to the northern geographic range expansion of this economically damaging insect in the temperate climates of North America., (Published by Oxford University Press on behalf of Entomological Society of America 2016. This work is written by US Government employees and is in the public domain in the US.)

Cereal leaf beetle, Oulema melanopus L., can be effectively managed in southeastern U.S. wheat, Triticum aestivum L., with scouting and a single insecticide treatment, applied at the recommended economic threshold. However, many growers eschew this approach for a prophylactic treatment, often tank mixed with a nitrogen application before wheat growth stage 30. The efficacy of a prophylactic and an integrated pest management (IPM) approach was compared for 2 yr using small plot studies in North Carolina and regional surveys across North Carolina and Virginia. Economic analyses were performed, comparing the total cost of management of each approach using the regional survey data. From a cost perspective, the prophylactic approach was riskier, because when cereal leafbeetle densities were high, economic loss was also high. However, fields under the prophylactic approach did not exceed threshold as often as fields using IPM. Total cost of prophylactic management was also $20.72 less per hectare, giving this approach an economic advantage over IPM. The majority of fields under the IPM approach did not exceed the economic threshold. Hence, from an economic perspective, both the prophylactic and IPM approaches have advantages and disadvantages. This helps explains the partial, rather than complete, adoption of IPM by southeastern U.S. wheat growers. Cereal leaf beetle was spatially aggregated across the region in 2010, but not in 2011. As a result, from an economic standpoint, prophylaxis or IPM may have a better fit in localized areas of the region than others. Finally, because IPM adoption is favored when it has a strong economic advantage over alternative management approaches, more emphasis should be placed on research to reduce costs within the IPM approach.

We investigated the use of nonwoven fiber barriers for control of cabbage maggot, Delia radicum (L.), and onion maggot, D. antiqua (Meigen). The barriers consist of arrangements of minute fibers loosely intertwined in "web" form. Results from a greenhouse experiment showed that manually applied graphite fibers placed at the base of broccoli plants reduced the number of D. radicum eggs by 64-98%, and that efficacy increased with greater fiber density. Using a melt extrusion process, we devised a method for on-site creation of nonwoven fibers of ethylene vinyl acetate (EVA). In field trials with broccoli and onion plants, EVA fibers significantly reduced the number of cabbage and onion maggots infesting plants. Fiber barriers provided comparable control to standard insecticide applications. The addition of blue, yellow, red, or black pigments, as well as optical brighteners that absorb UV light did not enhance fiber efficacy. Incorporation of capsaicin olfactory repellent to EVA also did not enhance fiber efficacy. Nonwoven fiber barriers may offer an alternative to insecticides for control of cabbage maggot and onion maggot and possibly other insect pests. Additional research is needed to improve the application process and to identify economically feasible and biodegradable compounds for fibers.