I quote:

" Compared to domestic honey bees, the Russian bees are more
than twice as resistant to attack by varroa mites, according to tests
by geneticist Thomas E. Rinderer and colleagues at ARS' Honey
Bee Breeding, Genetics and Physiology Research Unit in Baton
Rouge, La. "

end of quote.

As I understand the bees from Russia was imported because the
domestic bees (and other world wide A. mellifera population as well)
have zero resistance to varroa. I'm slightly confused. Can someone
kindly explain for me what is 'twice better than zero' ?

(2 x 0 = ?.....)

How many times the bee must be resistant  - compared to not
resistant bees - to be genuin resistant as A. cerana is? Means - to
be able to keep the varroa population at the 'bee survive level' without
any anti varroa treatment.

I'm be able to understand a comparison against A. cerana (40% of
cerana resistance or 80%... etc), but I have some difficulties to
understand this kind of mathematics (2 x 0).

Thanx

\vov