Performing Department
(N/A)
Non Technical Summary
The western honey bee is an essential pollinator for a variety of U.S. crops but its managed population is threatened by current and emerging pests and pathogens. Early detection of biotic threats to colonies is essential to maintain the pollination services provided by honey bees. Our goal is to improve the health of honey bees by reducing colony losses to pests and pathogens via the creation of a novel monitoring tool that is simple to use, does not rely on direct sampling of adult bees and brood, provides accurate identification of pests and pathogens, and can detect pests and pathogens at low levels of infestation/infection. The collection of environmental DNA/RNA (eDNA/eRNA) satisfies these criteria because it can be paired with high throughput sequencing to offer an indirect and non-targeted method to identify pest and pathogen communities. We propose to advance monitoring programs for honey bee pests and pathogens using a novel eDNA/eRNA approach. Specifically, we aim to build upon our existing experience with eDNA to: (1) determine if eRNA can be used to detect honey bee viruses in and around colonies; (2) determine if eDNA/eRNA can be used to detect emergent threats to U.S. honey bees by testing the methods in locations where potentially invasive species exist and (3) establish an eDNA/eRNA survey method that could be adopted for U.S. honey bee health monitoring programs. The resulting diagnostic tool would help reduce pollinator declines, improve colony health, and limit the impacts of invasive organisms on the U.S. honey bee industry.
Animal Health Component
100%
Research Effort Categories
Basic
10%
Applied
70%
Developmental
20%
Goals / Objectives
Our overall goal is to improve the health of honey bees by reducing colony losses to pests and pathogens via improved detection/monitoring techniques. Our specific aim is to develop eDNA and eRNA metagenomics as diagnostic technologies to improve honey bee monitoring and early detection of invasive organisms, and evaluate the feasibility of including this tool in future national monitoring programs (e.g., USDA APHIS National Honey Bee Pests and Diseases Survey).We will address this overall goal through the following objectives.(1) Objective 1. Determine if eRNA can be used to detect honey bee viruses in colonies and the surrounding landscape(2) Objective 2. Determine if eDNA and eRNA can be used to detect emergent threats to U.S. honey bees by testing the methods in locations where potentially invasive species exist:2a. Vespa mandarinia (northern giant hornet) detection in Washington State, U.S.2b. Apis species, V. mandarinia, and Tropilaelaps spp. detection in Thailand2c. Apis mellifera capensis detection in South Africa(3) Objective 3. Establish an eDNA/eRNA survey method that can be adopted for honey bee pest/pathogen monitoring programs in the U.S.
Project Methods
Objective 1 consists of screening different surfaces within and outside hives from our test apiary to determine where informative eRNA can be found. We will focus on surfaces that were ranked as easy to sample in our previous work as we want this technique to be adopted for large-scale monitoring, and not require too much additional time from beekeepers. Where surfaces allow, we will test two different collection techniques: moistened forensic swabs with viscose tips wiped across surfaces vs. spray/wash collection. Collected samples will be processed based on methods recently developed in our laboratory for RNA extraction and shotgun sequencing of RNA and DNA from royal jelly. The resulting data will be bioinformatically processed through standard pipelines: filtering, quality control, trimming, annotation, and taxonomic assignment. The results will be used to inform sampling protocols for screening for viruses in Objectives 2b and 3.For objective 2, we aim to test our established eDNA (prior work) and eRNA (Objective 1) protocols in locations of the native ranges of some of the greatest biotic threats to honey bees. While the focus for Objective 2 is on eDNA detection of arthropods, we also will process eDNA samples for microbes and collect eRNA for future screening for honey bee viruses. These samples will be stored in a -80°C.The incursion of the northern giant hornet in Washington, U.S. presents a good opportunity to test the ability of our established methods to detect this new arthropod pest affecting U.S. honey bees (Objective 2a). Our proposed work will complement the targeted protocol being developed and allow us to address the question: If the hornet is present in the area, would the eDNA technique be sensitive enough to detect it without someone otherwise visualizing it. We will test our established non-targeted metabarcoding method using two universal arthropod primer sets (targeting COI and 16S mitochondrial genes) to see they can detect the northern giant hornet. The research team will travel to Washington to complete the sampling regimen for this objective in collaboration with colleagues on site. We will target areas that northern giant hornets have been found before to give us the greatest chance of detection success. Samples will be taken from hive entrance reducers, hive detritus from trays, plant litter at the base of the hives, and water sources that honey bees are seen visiting. If no hornets are present, we can use DNA from nest materials, or dead insects, to test ours assays by placing small droplets of DNA in and around hives. A second researcher who does not know where DNA has been placed would collect the eDNA. Samples will be returned to the UF HBREL for processing.Thailand is home to five species of Apis, three of which are known to be invasive in other parts of the world. Furthermore, Thailand is within the native range of Tropilaelaps spp. and the northern giant hornet. Thus, Thailand represents an important site where we can test eDNA ability to detect the arthropod species that are organisms of concern in the U.S. (Objective 2b). The research team will travel to Thailand to collect and process eDNA samples as proposed in Objectives 1 and 2a.For Objective 2c, the research team will travel to the Cape Town region of South Africa and collect eDNA samples following the same protocols and targeting surfaces outlined in Objective 2a. As A.m. capensis can be found ranging freely in parts of South Africa outside of managed colonies, nesting cavities occupied/previously occupied by honey bees will also be tested as a source of eDNA. The DNA will be extracted and processed as outlined for the other objectives.In Objective 3, we will lead a national ring test in which we invite colleagues from around the U.S. to collect eDNA and eRNA samples using our methods and ship the samples to us for DNA/RNA extraction, sequencing, and bioinformatics pipelining. We will develop sampling kits to ship to our ring test collaborators and provide them with detailed methods regarding how to collect the samples and return them to the UF HBREL. This will allow us to test the feasibility of scaling up the method for national monitoring for new and emerging issues, and detect any additional research needed before this diagnostic tool can be implemented. The ability to use eDNA and/or eRNA for monitoring would limit the need to collect and ship live bees, require less time from beekeepers, and could increase the reach and scope of national monitoring programs. A standard bee health survey will also be completed (based on the current Bee Informed Partnership survey), and e-mailed to co-PD. This information will not be made available to researchers in the PD's laboratory to allow us to ground truth any of our findings without biasing data processing in any way.