Sustainable management of invasive species
Authors:   , Benthall Kelsey Jo 
Published: March 2024

[EMBARGOED UNTIL 12/1/2024] Integrated pest management combines an array of management strategies to combat pest species in an environmentally minded manner. However, these tactics are increasingly disrupted by climate change, insecticide resistance, chemical restrictions, and invasive species. The current reports of non-native species introductions have been correlated to historical trade volumes, suggesting that integrated pest management programs will need to adjust to mitigate current and future invasions. The main objectives of this dissertation were to: 1) evaluate the efficacy of an attract-and-kill strategy targeting Japanese beetle, 2) quantify how attract-and-kill impacts arthropod short- distance dispersal in an agricultural setting, and 3) assess the potential for fall armyworm management using mating disruption. We evaluated long-lasting insecticidal nets as an attract-and-kill tactic to manage Japanese beetle. We compared defoliation, arthropod abundance, and seed damage between soybean fields treated with insecticidal nets and grower standard pyrethroid applications. We collected weekly sweep samples during soybean stages V4 through V7 to sample arthropod abundance. Weekly whole-plant defoliation assessments were recorded on 50 plants per treatment at V1 through R7. At the end of the growing season, we assessed seed production and quality. We found that attract-and-kill treatments reduced non-target effects on beneficial species. To evaluate arthropod movement between soybean fields and the surrounding natural habitat, we used mark-capture by applying a protein immunomarking technique and enzyme-linked immunosorbent assays (ELISA). We applied a 33 percent cow's milk solution to soybean fields and a 10 percent chicken egg white solution to the surrounding natural habitat three times throughout the growing season. Arthropods can become marked through direct contact during the protein solution application or by external contact with marked foliage. We collected sweep samples in both habitats 24 hours after protein applications, and then prepared key arthropods for ELISA analyses to determine the presence of each protein mark. We found that more unmarked arthropods in soybean fields compared with natural habitats. Also, arthropods marked in soybean typically remained in soybean while most arthropods marked in natural habitats typically remained in the natural habitat. To evaluate if mating disruption is an effective management strategy for fall armyworm, we conducted a study with two mating disruption techniques under both high and low populations. We compared fall armyworm trap captures, kernel injury, vegetative damage, and caterpillar abundance in corn fields treated with either mating disruption or grower standard. During 2022, we evaluated the efficacy of two experimental dispensers targeting fall armyworm (Strip-Dispensers and Mega- Dispensers). During 2023, we evaluated fall armyworm microencapsulated sprayable pheromone. We found that mating disruption has the potential to reduce kernel injury and the number of fall armyworm collected in fields. There is an increasing need for additional behavioral management tools adopted into IPM programs. Particularly for invasive species as current management tactics are increasingly disrupted by climate change, insecticide resistance, and chemical restrictions. Invasive species are arriving in novel habitats at accelerating rates and tend to cause severe economic and ecological damage. Behavioral management tactics such as mating disruption, push-pull, biological control, and attract-and-kill may have potential to work for invasive species management to mitigate damage while also reducing selective pressures on insecticide resistance.