Hi Everyone,
On the question of cross resistance between apistan and bayvoral.
If the mites are resistant to one yes they are resistant to the other
as well. This was clearly seen in the data obtained when fluvalinate
resistant varroa were found in South Dakota USA last fall.  In that
case neither apistan nor bayvoral provided any significant control of
the varroa mites in those colonies.  So the only benefit to have both
available is you get to pick which one you want to use.  You need to
have another material with a different chemistry available to rotate
with for resistance management.
 
blane
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Blane White
MN Dept of Agriculture
St Paul, MN
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