Articles
This is an article that I wrote for the FWCBS newsletter, and have not used yet. It is very interesting, but gets a little technical. If you like this check out the original article on Charlie's Web.
Anthocyanin
While surfing the World Wide Web, I checked out Charlie's Web, a frequent hangout for bromeliad type people. There I found an interesting article written by Jack Sullivan for The Carnivorous Plant Newsletter. It was about the red coloration found in bromeliads and other plants. The article was some what technical, but I waded through it, and thought I would report some of the interesting stuff. If you want the full article go to http://www.fixnet.com/~cdills/specialtopics/anthocyanin.html, or send me a dollar bill, and I will send you a color copy with the organic chemical ring drawings and everything, including the bibliography.
The color change in bromeliads and many other plants is due to anthocyanin pigments. They are a water soluble pigment found in most land plants, and not in marine plants, animals or microrganisms. The flowers and other plant parts obtain shades of red, blue, purple, yellow and every color except green from the anthocyanin pigments.
These pigments seem to play several different roles in the life of these plants. One is to attract insects for the purpose of pollination and predation in the case of carnivorous plants. Some bromeliads turn a vivid red color for a bloom period, and then return to a normal shade of green chlorophyll for photosynthesis. This is a biochemical device that can be switched on to assist pollination, and then degraded by plant enzymes when no longer needed to attract the insects.
The roll of sun screen is also played by the anthocyanins. Exposure to too much sun can harm most bromeliads, as we all know. As a defense plants can produce these pigments to protect their vital DNA. This produces beautiful coloration in some of our favorite bromeliads. The more sun a bromeliad can stand usually the more vivid is the color. The difficulty arises in finding the intensity of sunlight that will produce the maximum color without sunburning the plant.
Another role for anthocyanins is to serve as an anti-feedents, to deter predatory animals. These chemicals taste bad, and many poisonous plants are very colorful. This may not play as important role in bromeliads as other plants. Epiphytes usually do not suffer from animal predation, and most bromeliads have spines for protection.
Pollination and ultraviolet radiation damage seem to be the main advantages to anthocyanins in the bromeliad family. Anthocyanins make our hobby a very colorful one.
So next time you marvel at the deep, rich color of your favorite bromeliad, remember, you have anthocyanins to thank for that magnificent show.