> If we continue to bring bees from mite free areas into mite infested areas,
> I doubt we can improve the degree of mite resistance of our bees. If  we
> persist doing so, I believe we are fighting against nature.
 
My understanding of the resistance mechanisms are that they do not
relate specifically to 'mites'.  That is, the behaviour of bees that
allows for them to successfully resist mites does not have anything
to do with whether or not they have been exposed to mites.  Best way
to explain it, or at least the way it was presented to me, is that
you don't *have* to expose a hive to American foulbrood to breed for
AFB resistance.  What you are selecting for, in that case, is hygenic
behaviour (uncapping cells that haven't emerged, then removing the
contents in a timely manner).  'Resistance' or 'susceptibility' to
mites is a hygenic behaviour not specific to having a mite present...
 
  (\      Nick Wallingford
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