Project Overview
Commodities
- Animals: bees
Practices
- Animal Production: animal protection and health
- Crop Production: beekeeping
- Education and Training: on-farm/ranch research
- Farm Business Management: farm succession
- Sustainable Communities: sustainability measures
Proposal summary:
Varroa are currently responsible for greater losses of colonies than are any other biological threat, requiring
commercial beekeepers to spend a substantial amount of time treating colonies with chemicals. Integrated pest
management (IPM) is key to sustainable operations by reducing the labor associated with treating colonies, miticide costs, and loss of bees. Addressing these issues will result in increased profits and sustainability. A fundamental tenant of IPM is to use genetically resistant stock to improve productivity. This project focuses on the genetic aspect of IPM.
Some Florida queen producers actively select their own stock for local adaptation, overall hygiene, vigor and mite resistance. We plan to include these producers in this study. We will determine overall Varroa populations in approximately 500 colonies by performing standard alcohol washes on 300 worker bees, then collecting nurse bees for SNPs analysis, and finally rating vigor and defensiveness. The best 30 colonies with the lowest Varroa populations will be marked and set aside, then await the results of the SNPs assay; based these results further testing using MBB and PKB assay will occur.
This will aid Florida queen bee producers who, as a result of our
scientific genetic data, can make more effective breeding
decisions based on empirical information, rather than visual
perception and instinct. As part of this process, the
producers will be part of the field analysis and data collection.
Thus they will be able to perform the screening tests themselves
by the end of the study.
Project objectives from proposal:
We plan to sample at least 500 colonies in operations managed by three different queen producers in Florida. After
discussing stock selection methods with queen producers, we will inspect their colonies and assign them a unique number. First, we will assay these colonies for Varroa populations using a standard alcohol wash. The alcohol wash is generally
accepted scientific method for accurately measuring the level of infestation by collecting 300 bees, placing them in a jar of
alcohol, shaking them for 60 seconds, decanting off the liquid and counting the total number of mites that were washed off of the bees. Secondly, for genetic SNPs sampling, we will collect very young nurse bees, place them in tubes of
ethanol. Then the samples will be sent to Harpur lab at Purdue. Lastly, based on this raw field data, we can immediately identify which are the best colonies that will be tested for MBB and PKB.
MBB is defined by a honey bee biting one or more legs off a Varroa.An assay has been developed by Dr. Greg Hunt at
Purdue University (Hunt & Andino ABJ 2011) for accurately measuring the proportion of chewed mites in a colony.
This will yield measurable results, and a potential tool for breeding selections. The method has two major components,
collection of mites and evaluation of chewed legs. The collection of mites in the field by beekeepers is simple.
(1) An oiled board is inserted over the bottom board (floor) of the hive. (2) The board is allowed to remain in the hive for 24-48 hours. (3) The mite boards are removed from the hives, and brought to safe processing area/lab. The second
component is evaluation. (4) Sift through the contents and collect the dark mature mites. (5) Glue/set the mites "legs up" on a glass microscope slide/petri dish and count the total number of Varroa (6) View each mite on the slide under a low power microscope/15×-handlense and count how many mites have chewed/missing legs. (7) Calculate the MBB, as a percentage, example: 12 chewed mites/36 total mites = 33% of mites having chewed legs. The collection method is simple for beekeepers to perform in field with minimal training and tools. The evaluation component, steps 4-7, requires more skill and is labor intensive/time consuming. Fortunately, this can be done later, when beekeepers have more time.
Students at the University of Florida will be involved in counting the chewed mites, and some of the field work.
Statistical analysis of the results will be performed and presented in the final report.
Pin-killed Brood assay is performed by using an entomological pin and piecing capped brood. A section of brood frame is
marked so 50 cells are pieced, killing the pupae, the worker bees will remove the dead pupae. After 5-6 hours the frames are measured for the percentage removed. This is safer than the freeze killed methods which require the handling of dangerous liquid nitrogen. These results are a proxy for VSH hygienic behavior.