Chris,
>>Can you suggest which particular genetically inheritable characteristics
>>might make a strain of honeybee less susceptible to nosema?

Joe
> Simply by
> selecting from the top 10 %  overall performers,  would have been
> effectively selected for high varroa resistance. As a result, I am placing 
> much more weight on selection for over all
> performance and much less weight on time consuming testing and counting
> techniques.

I can not confirm the mechanism how some bees tolerate nosema. But if 
someone wants to have such bees the best way is to breed from colonies 
selecten by low nosema counts. I know a beekeeper in Denmark who has had low 
nosema counts as one selection critearia for years, and he had lowered his 
nosema numbers a lot. Test all your breeder colonies and use the counts as 
selection criteria.

Testing is easy (= low cost)  for him as it is done in a school for kids 
with learning problems. The counting is a part of teaching and kids like it 
because it is more interesting than just theory of biology.

Ari Seppälä
Finland

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