I work with the chytridiomycete Synchytrium endobioticum.
The overwintering body is a resting spore. This is an
obligate (to potato) fungus and reproduces in potato
tissue cells. It does not produce a mycelium. It is
difficult to tell from light microscopy if the spore
is viable or not. Population viability can be estimated
somewhat in bioassay with potatoes, but I need a method
to identify single spore viability. I have tried many
flurochromes - settling on acriflavin - but it is not
a surefire system. There is not much that I can find in
the literature to help me. Are there some new products
out there that I can try? Any suggestion will be much
appreciated. Thanks. Mike Hampson (hampsonm at NFRSSJ.agr.ca).