vital stains\lignin\roots

[foc]

Hi!
I need some help!!!!

I am interested in detailed methods (protocols)  for detection of lignin,
polyphenolics  and also Oxygen radicals in plant tissues, as well as useful
vital stains to check if the fungal and root cells are dead or dying. 

The material to be studied will be thin sections and hand cut sections of 
fungi infected young roots.


What type of fix should one use? Should the material be fixed or not? is
also an important detail when examining the sections. Have planned to look
at both fresh and formaldehyde fixed root material.