Arthropods associated with faba bean (Vicia faba L.) in eastern Virginia and chemical control of a key pest

Abstract

Faba bean (Vicia faba L.) is a cool‑season legume with growing potential in the Mid‑Atlantic United States, yet little is known about the arthropod communities or pest pressures associated with this crop regionally. This thesis synthesizes global literature on arthropods interacting with faba bean and provides the first Virginia‑based field survey and insecticide efficacy data relevant to local production. Worldwide, more than 100 arthropod species—including aphids, plant bugs, beetles, predators, and pollinators—are reported on faba bean. Field surveys conducted across Virginia in 2025 documented 33 taxa interacting with the crop, including 22 pest species, 9 predators, 6 pollinators, and 1 parasitoid group, with several species confirmed reproducing on plants. Beneficial insects such as coccinellids and syrphids were consistently present, while pollinator visitation was limited, dominated by Xylocopa virginica. Chemical control trials evaluated seven insecticides against the stink bug Nezara viridula using greenhouse assays and weathered‑foliage bioassays. Bifenthrin, lambda‑cyhalothrin, and the novel insecticide isocycloseram produced the fastest knockdown and longest residual activity, maintaining mortality up to 21 days after treatment. Neonicotinoid and diamide products showed shorter residual activity. Together, these results provided the first characterization of arthropod interactions with faba bean in Virginia and identified effective chemical tools for managing stink bugs. This work establishes a foundation for integrated pest management strategies