how to amplify a fungus which is in the host tissue - (Nov/07/2012 )
If you know the sequence of the fungus, you can design fungus specific primers for the region of interest. If you don't know the sequence, you may need to look at some primer walking where you sequence from a primer, then use that to design another primer further along the DNA which you then sequence from...etc.
Fungal ITS specific primers
Check this article
http://www.biomedcentral.com/1471-2180/5/28
Thank you , I ordered specific primers for ITS region from the article you suggested