IMHO,
I think you need to think of hives of bees developing resistance to mites.
It will do no good for a particular worker to be resistant.
Since drone brood is where the mites tend to concentrate, a particular
drone that survives the infestation, could pass along what ever quality to
the next generation.
With the general requeening every year, if we were to have a queen with
total resistance  to mites, she would just be replaced as a matter of
routine beekeeping practice and her  qualities of resistance lost.
Now if you were to take some of her drone and use them to mate with a
virgin queen, then the resistance trait  could have a chance of being
passed on.
 
It is like wanting a good hunting dog and buying new dogs every year and
never taking the best hunting dogs and breeding from that stock..
You might get a great hunting dog, but how will that benefit you  when you
replace her from another mailorder dog supplier?
Dusty
 
>Although it is probably quite a long shot I think that it is possible
>that the bees could develop an immunity to the mites.  Quite a number of
>trees produce toxins in their leaves if they are attacked by insects and
>I beleive that your own body will produce a sort of insect repellant if
>you refrain from washing.  I don't think that we should confine immunity
>to the cellular level.
>
>Harry
>Scotland
>
>
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