Location: Invasive Species and Pollinator Health
Project Number: 2030-22000-029-047-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Oct 1, 2019
End Date: Jun 30, 2020
Objective:
The goal of this project is to provide effective biological control agents for bagrada bug, Bagrada hilaris (Pentatomidae), a new and highly damaging exotic pest of cole crops in California. Specific objectives are to: 1) measure the host specificity of bagrada bug parasitoids recently collected in Pakistan; 2) survey California for resident natural enemies of bagrada bug.
Approach:
Funds will be used to test candidate parasitoids and survey resident natural enemies in California. Host specificity tests of two parasitoid species collected in Pakistan in 2016 (Trissolcus hyalinipennis and Gryon sp.) will be conducted inside quarantine facilities at the USDA-ARS, Albany. At least 8 species of stink bugs will be cultured for testing, most native to Western United States. Host specificity testing will be measured in two phases, first using ‘no-choice’ testing followed by ‘choice’ tests. During the first phase the parasitoid will be exposed to just one species of egg. Those non-target stink bug species successfully attacked by the candidate parasitoid will be subjected to ‘choice tests,’ whereby the parasitoid is exposed simultaneously to eggs of two stink bug species: bagrada bug and one of the non-target stink bugs. Field surveys for resident natural enemies of bagrada bug will be conducted throughout California during the cole crop production season. Surveys will target cole crop production areas with high densities of bagrada bug: the southern California desert, central coast (Monterey County), southern San Joaquin Valley, and Yolo County in northern California. Sentinel eggs will be obtained from laboratory colonies, and will be glued to index cards, which will be placed on the ground, where the bagrada bug lays the majority of its eggs, in both crop fields and patches of weed hosts of bagrada bug. Images will be taken of eggs before and after they are returned to the laboratory to record damage by predation. Pheromone baited traps will be placed near eggs to increase the likelihood of attracting parasitoids and to estimate population abundance of bagrada bug.
