dna extraction from plant tissue infected with fungus - (Jan/24/2012 )

Hello!

I have to investigate DNA fragmentation on plant tissue infected with fungus using DNA laddering. This is a new field of investigation for me so I would appreciate any advice. I am especially concern about extraction of DNA from plant sample infected with fungus. Is there any way to distinguish between plant and fungus DNA?
Please help!
Zorana

Other than looking for markers for the fungus and for the plant respectively, there is no way to distinguish between the two when they are just DNA. If the plant is infected only superficially, on the surface for example, you may be able to wash the plant tissue in a solution of bleach to remove the fungus and destroy any DNA left behind.