Using Tri Reagent to Extract Plant DNA

[Mary_Wood at BAYLOR.EDU]

I've been TRYING to use a product called Tri-Reagent to extract genomic DNA from 
tobacco plants.  Supposedly the DNA is in the interphase and phenol phase of the 
mixture after removal of RNA in the aqueous phase.  But I am getting very little 
DNA -- about 200 ng from 100 mg of plant tissue after homogenizing in liquid 
nitrogen.  Has anyone used this product to extract genomic plant DNA?  How did 
you do it?