Beneficial (?) fungus in D. pseudoobscura collection

[A.J. Davis]

All Drosophila species, including D mel, do much better when 
vegetable (powdered spinach for example) is added to the 
medium.  Part of the reason is the additional vitamins this 
provideds - conventional medium is low in available 
vitamins.  Obscura group species will certainly benefit. 
Conventional medium is also far too rich in carbohydrate, 
particularly sugar, which favours fermenting yeasts against 
other microrganisms and i suspect, though i havn't tried, 
that sugarless medium with cooked vegetable and/or fungus 
(mushroom) might suit obscura more.  I'd love to have this 
tested but who'd fund such a 'boring' study ?

Andrew

For conventional lab. rearing living food is problematic but 
if you're having real problems then try inocculating the 
medium with microrganisms from the substrate the flies were 
originally reared from.

Andrew Davis
University of Leeds, Yorkshire
England, LS2 9JT   UK

a.j.davis at uk.ac.leeds