I'm not currently working on the subject but I can be a valuable contributor. It is one of the research areas of our research group.
I provide below some useful references on the subject for your perusal:
Newmaster and Ragupathy 2010 Ethnobotany genomics - discovery and innovation in a new era of exploratory research. Journal of Ethnobiology and Ethnomedicine 6 (1):2
Newmaster and Ragupathy 2009 Ethnobotany Genomics - Use of DNA Barcoding to Explore Cryptic Diversity in Economically Important Plants
Ragupathy et al 2009 DNA barcoding discriminates a new cryptic grass species revealed in an ethnobotany study by the hill tribes of the Western Ghats in southern India. Molecular Ecology Resources 9:164-171
Feel free to let me know if you have any further inquiry.