Project Number: 8010-22000-031-054-I
Project Type: Interagency Reimbursable Agreement
Start Date: Jun 1, 2021
End Date: Sep 29, 2022
In the past, we have discovered a few natural enemies of Asian longhorned beetle (ALB) in Asia, but the impact of these natural enemies on ALB is unclear and more extensive surveys and evaluations of these natural enemies are needed. We have also found one North American natural enemy that can readily attacked ALB. Our goal is to continually discover, import and evaluate Asian natural enemies for biological control of ALB (Objective 1), and (2) evaluate the potential of the North American natural enemy against ALB (Objective 2).
For Objective 1, surveys will be conducted in northeastern natural and urban planted forests in Gangwon and Seoul, South Korea, and in Beijing, Guizhou and Yunnan, China using sentinel logs infested with live ALB eggs and/or young larvae. At each survey site, we will deploy 5-10 sentinel logs, once per month, from June to September. We will also conduct sampling of infested trees by removing barks with ALB eggs or young larvae from naturally infested trees. All sentinel logs will be collected after a 3-week exposure in the field and dissected to collect parasitized eggs or larvae and determine the fate of each exposed ALB egg or larva. Percentage parasitism will be determined. All parasitized ALB eggs or larvae will be reared until the parasitoids have developed into pupae or adults before they are shipped to the ARS-BIIRU for rearing and quarantine evaluations of the parasitoids for their efficiency against ALB, host specificity and climatic adaptability. For Objective 2, we will evaluate one of the most common North American parasitoids Ontsira mellipes for its ability to detect and attack ALB larvae in field release trials. We have devleoped optmal rearing methods for this parasitoid, and obtained federal and state permits for the field trial with parasitoid release and deployment of ALB infested logs in regulated ALB zones in Worcester, MA. Field release of O. mellipes will be conducted in 6 field sites within the ALB quarantine zone in Worcester. We propose two releases of O. mellipes ¬and two deployments of ALB sentinel logs each month when ALB larvae could be susceptible to the parasitoids’ attack in the field from June to September 2021. Each log will be securely placed inside a protective cage constructed of 23-gauge hardware cloth to provide a second level of security containment for the ALB for the sentinel logs deployed in the field. ALB will be mass-reared at APHIS Otis lab where sentinel logs will also be prepared. Parasitoids will be mass-reared at BIIRU and shipped to the field sites for release.