By use of genetic methods, three different
>  geographically isolated mite populations
>  could be distinguished in America
>  These groups may represent populations
>  with different virulence (or perhaps
>  tolerance levels of the host).

Hi Pete,
I don't have the reference at hand (am rushing down to the almonds
this morning).  It appears that the more virulent Korean haplotype of
mite displaced the less virulent Japan type in South America since
this paper was written.  Yet the bees adapted.
Randy

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