Location: Invasive Species and Pollinator Health
Project Number: 2030-22300-032-018-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Aug 1, 2020
End Date: Jul 31, 2022
1) Collect and maintain candidate stinkbug species for non-target testing and improve rearing protocols as needed; and 2) Test the host specificity two bagrada bug parasitoids, Gryon gonikopalense and Trissolcus hyalinipennis.
Field surveys will target the San Joaquin Valley and Yolo County in northern California. Sentinel eggs will be placed at locations near cole crop production areas with high densities of bagrada bug and used to measure local predation and parasitism. Eggs will be produced at CDFA’s quarantine facility in Sacramento. Eggs will be killed by freezing them at -80°C, to avoid introducing new bagrada bugs to crop fields; one- to two-day-old eggs generated from lab cultures will be held at -80°C for fifteen minutes then stored at standard refrigeration temperatures for up to one week before placement in field. Frozen bagrada bug eggs will be glued to water resistant card stock which is then placed on the ground, where the bagrada bug deposits the majority of its eggs. Cards will be placed in or near crop fields and patches of known weed hosts of bagrada bug. They will also be placed on the leaves of nearby host plants. Eggs will be placed at 3-6 locations during the cole crop production season. Cards will be placed at each location at least two times during the season, from late July to October. After cards are in the field for 3 to 5 days they will be returned to laboratory, where the number of eggs damaged from predation will be recorded within seven days. Eggs will be held for an additional 4 to 6 weeks for parasitoid emergence, which will then be identified to species. At least one Dead Inn trap will be placed at each location. Traps will we baited with generic stink bug pheromones or crushed alyssum. County cooperators will be contacted prior to the planting of crops to aid in best placement of sentinel eggs and traps. Non-target stinkbugs will be collected at sites using sweep nets or by visually inspecting vegetation.