Entomology beyond research and education: 2022 student debates.

The 2022 student debates of the Entomological Society of America (ESA) happened during the Joint Annual Meeting of the Entomological Societies of America, Canada, and British Columbia in Vancouver, BC, and addressed entomological aspects beyond research and education. The Student Debates Subcommittee of the ESA Student Affairs Committee and the participating student team members communicated for 8 months and prepared for the debates. The theme of the ESA meeting in 2022 was "Entomology as inspiration: Insects through art, science, and culture". There were 2 unbiased speakers who introduced the debate topics as well as 4 teams who debated the following 2 topics: (i) Is forensic entomology viable in criminal case investigations and court cases today? and (ii) Are insects being treated ethically in scientific research? The teams prepared for about 8 months, debated their arguments, and shared their thoughts with the audience. The teams were judged by a panel and the winners were recognized at the ESA Student Awards Session during the annual meeting.

Allium leafminer (Diptera: Agromyzidae) host preference: implications for developing a trap cropping strategy.

Allium leafminer (Phytomyza gymnostoma Loew) is an emerging invasive pest of Allium crops and has been threatening Allium crop production in the eastern United States since its introduction in 2015. Phytomyza gymnostoma can cause substantial economic loss in leek crops when late instars tunnel into the lower portion of the plant, which often renders the crop unmarketable. With limited management tools that are cost-effective and practical, especially for leeks produced in organic systems, we examined the attractiveness of other Allium crop species that might be considered in a trap cropping strategy. In 2021 and 2022, controlled environment choice tests and field trials were conducted to evaluate host preference of P. gymnostoma among Allium crop species including chives, scallion, an onion and scallion hybrid, and leek. We also assessed preference of P. gymnostoma for scallions that varied in size/age. Results from field trials indicated that only chives had more oviposition marks, cumulative numbers of eggs, and a higher density of P. gymnostoma larvae and pupae than leeks. Larger/older scallions had more oviposition marks and higher P. gymnostoma densities than smaller ones in controlled environment choice tests, but this size/age preference was not evident in field trials. Based on our findings, chives could be considered as a potential trap crop for minimizing P. gymnostoma damage in leek crops.

Biocontrol of Wireworms (Coleoptera: Elateridae) Using Entomopathogenic Nematodes: The Impact of Infected Host Cadaver Application and Soil Characteristics.

Wireworms have become a significant menace to cereals in the Northern Great Plains. Therefore, research toward developing effective control methods such as biological control with entomopathogenic nematodes (EPNs) is warranted. Two strains, each of two EPN species, Steinernema carpocapsae (Weiser) and Steinernema riobrave Cabanillas, Poinar, and Raulston in the form of infected Galleria mellonella (L.) cadavers were evaluated against wireworms in field and greenhouse. In field experiments, none of the four EPN strains were found effective against wireworms. However, in the greenhouse test, three of the strains, S. carpocapsae (All and Cxrd) or S. riobrave (355) applied in cadavers killed 50-68% of the sugarbeet wireworm, Limonius californicus (Mannerheim) was associated with 8-24% plant damage at 35 d after treatment (DAT), when seeds were treated with imidacloprid. The mortality range was 40-56% with 57-75% plant damage observed at 35 DAT, when seeds were planted without imidacloprid treatment. Synergistic effect among imidacloprid and S. carpocapsae (Cxrd) or S. riobrave (355) was observed in regard to L. californicus mortality. Additionally, effects of soil texture, moisture, and temperature on the infection rate of EPNs against L. californicus were examined in the laboratory. Limonius californicus mortality was not significantly affected by either soil moisture or soil types maintained at field capacity moisture levels. However, soil temperature showed a significant effect on L. californicus mortality. Overall, imidacloprid enhanced the infection and killing ability of EPNs against L. californicus and S. carpocapsae (All and Cxrd) strains were the virulent strains in different soil experiments.

Montana Native Entomopathogenic Nematode Species Against Limonius californicus (Coleoptera: Elateridae).

Wireworms are destructive soil inhabiting polyphagous pests in the Pacific Northwest and Intermountain region of the United States. Continuously increasing wireworm populations and damage in small grain crops such as spring wheat in Northern Great Plains has become a challenge for growers. Due to unavailability of effective control measures, alternative methods, including biological control agents such as entomopathogenic nematodes (EPNs) are needed. Native/indigenous EPN species are expected to have better potential than exotic species to control the local insect pests. Two Montana native EPN species (Steinernema feltiae and Heterorhabditis bacteriophora) were tested against, Limonius californicus (Coleoptera: Elateridae) in laboratory and shade house studies. In the laboratory bioassay, two isolates of S. feltiae at the rate of 28,000 IJs/five larvae killed 48-50% of the insects within 4 wk. Heterorhabditis bacteriophora was not able to cause >30% L. californicus larval mortality. None of the two isolates of S. feltiae performed well against L. californicus when tested in different soil types. Similarly, two isolates of S. feltiae that were tested killed only 20-25% wireworms in a shade house trial that did not differ significantly from the control treatment. Four weeks after EPN treatment in the shade house trial, the percentage of wheat plant damage from L. californicus ranged from 30 to 40% in the presence of S. felitae, not differing statistically from control. These results suggest that S. felitae have limited potential in managing wireworm populations.

A Review of Interactions between Insect Biological Control Agents and Semiochemicals.

Biological control agents and semiochemicals have become essential parts of the integrated pest management of insect pests over recent years, as the incorporation of semiochemicals with natural enemies and entomopathogenic microbials has gained significance. The potential of insect pheromones to attract natural enemies has mainly been established under laboratory conditions, while semiochemicals from plants have been used to attract and retain natural enemies in field conditions using strategies such as trap crops and the push-pull mechanism. The best-known semiochemicals are those used for parasitoids-insect pest-plant host systems. Semiochemicals can also aid in the successful dispersal of entomopathogenic microbials. The use of semiochemicals to disseminate microbial pathogens is still at the initial stage, especially for bacterial and viral entomopathogens. Future studies should focus on the integration of semiochemicals into management strategies for insects, for which several semiochemical compounds have already been studied. More effective formulations of microbial agents, such as granular formulations of entomopathogenic fungi (EPFs), along with bio-degradable trap materials, could improve this strategy. Furthermore, more studies to evaluate species-specific tactics may be needed, especially where more than one key pest is present.