Hi Allen and Everyone,
Tibor Szabo is doing a similar selection for varroa resistance and reports incouraging results after 4 or 5 years of selection.  He has published updates each of the last several summers from the pervious summer's data.  They are continuing the selection but have clearly shown that you can select for varroa resistance while continuing to treat colonies for varroa as long as you continue to breed from the colonies with the lowest mite counts.  Of course you also need to continue to select for other important characters as well like honey production, wintering, and gentleness, etc.  You might want to first select your usual breeders and then use the mite count to pick the best of these for actual breeding.  Of course one can also use some of these best colonies for drone source colonies making sure to avoid too rapid inbreeding.

Clearly, Tibor has shown that such selection can and will work.

FWIW

blane


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Blane White
MN Dept of Agriculture
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