There is a purple fast plant cultivar that is used in teaching
exercises on Mendelian inheritance of purple pigmentation and effects
of light level on anthocyanin development.
http://www.carolina.com/fastplants/seed_stock/Purple%20Stem%20hairy.pdfhttp://www.fastplants.org/resources/genetics/monohybrid.htmlhttp://www.fastplants.org/resources/genetics/dihybrid.html
It might be interesting to include an exercise on betalains, which
replace anthocyanins in over 11,000 species in about 10 families.
Introduction to the Caryophyllids: The Betalain Bunch
http://www.ucmp.berkeley.edu/anthophyta/caryos/caryophyllids.html
The most familar betalain source is probably red beet. A common student
project involves the effect of temperature on membrane stability in red
beet root. Membrane stability is measured by the amount of betalain
leakage:
http://www-saps.plantsci.cam.ac.uk/records/rec82.htm
The effect of other factors, such as pH, on beet membranes or betalains
can also be examined:
Reid, M. S., Paul, J.L. and Young, R.E. 1980. Effects of pH and
ethephon on Betacyanin leakage from beet root discs. Plant Physiology
66(5): 1015-1016.
http://www.pubmedcentral.gov/articlerender.fcgi?tool=pmcentrez&artid=440771
Some other labs are described in the following articles:
Daniel, T.F. and T. Johns. 1982. A laboratory on chemotaxonomy: the
systematic distribution of betalains. Amer. Biol. Teacher 44: 308-310.
Kamrin, Anne A. and LaVan, Joan S. 1984. Demonstrating osmosis and
anthocyanins using purple onion. Amer. Biol. Teacher 46: 116-117.
David R. Hershey