Location: Application Technology Research
Project Number: 5082-21000-001-050-A
Project Type: Cooperative Agreement
Start Date: Sep 1, 2021
End Date: Jul 31, 2025
Cooperator will conduct research to address the following objectives: 1) Predict the risk of infestations in orchard and nursery crop systems through improved understanding of AB biology and ecology, 2) Implement comprehensive management strategies, and 3) Transfer research-based information to stakeholders.
To address objective 1, the cooperator will inoculate apple trees with fire blight to assess the influence of infection on ethanol production and ambrosia beetles. Count data of attacks, specimens, and fungal gardens will be determined. Similarly, experiments will be conducted to assess the acquisition and transmission of fire blight by ambrosia beetles. Surface sterilized lab reared beetles will be exposed in vials to filter paper discs treated with a highly virulent strain of fire blight. Fire blight acquisition on the beetle cuticle will be determined. Transmission assays will also be conducted to determine if beetles can transmit fire blight to healthy trees. The association between Phytophthora root rot and ambrosia beetle attacks will also be examined by inoculating trees with isolates. Count data of attacks and dissected specimens will be quantified. Objective 1 will also be addressed by the cooperator to assess the pathogenicity and virulence of auxiliary and symbiotic fungi associated with ambrosia beetles to elucidate the basis for branch die-back and tree death. Tree and trap surveys will be conducted biweekly from early spring through fall to gain insight into the diversity of auxiliary fungi associated with black stem borer (BSB) and granulate ambrosia beetle (GAB) and their galleries. Fungal cultures will be identified using morphology and sequencing of the ITS region and additional genes for genera and consistently isolated species. Fungal species consistently recovered from beetles and galleries will be screened using a detached twig assay. Objective 2 will also be addressed by testing conventional and reduced risk insecticides, insecticide-impregnated netting, repellents, and plant defense elicitors for inhibiting ambrosia beetle attacks and/or colonization using potted species/cultivars of apple under flood stress regimes. Following the field experiment, trees will be dissected to identify and quantify adult and brood ambrosia beetles within the galleries. To address objective 3, cooperators will conduct traditional in-person meetings, web-based approaches (blogs,YouTube, social media), and outreach publications.