Re: How does caffeine effect the growth of plants?

The answer in the references cites several articles about caffeine effects in 
plants. There is evidence that caffeine affects plant cytokinesis. One study 
used spiderwort (Tradescantia) stamen hairs which are chains of single cells 
easily viewed under a microscope. However, it seems questionable whether 
caffeine could be absorbed by plant roots and transported to stamen hairs under 
natural conditions. Therefore, it might be more relevant to examine caffeine 
effects on roots.

If your library has Science Citation Index, BIOSIS, AGRICOLA or other databases 
or abstract journals you should be able to find more literature. Ask your 
librarian for guidance if you are unfamiliar with searching the literature. You 
can often obtain copies of articles via interlibrary loan if your library 
doesn't carry those journals.

The problem with using caffeine in tea or coffee is that you don't know the 
exact caffeine concentration plus they contain so many other ingredients that 
may affect plant growth, particularly mineral nutrients. Especially avoid 
sugared sodas because the sugar harms plants because of an osmotic effect. A 
diet soda might be the best choice if you cannot use plain caffeine. You can 
purchase caffeine from a chemical supply company such as Sigma: www.sigma-
aldrich.com

If you want to look at cell division effects then spiderwort would be a good 
plant since it is easy to observe the stamen hair cells dividing. If you want 
to observe more general effects on plant size and have a fluorescent light 
bank, Wisconsin Fast Plants might be a good choice because they grow rapidly, 
completing their seed-to-seed life cycle in about 5 weeks. If you wanted to 
look at caffeine effects on root cytokinesis, it would be best to grow plants 
in solution culture or hydroponics. 

References


Re: Does Caffeine affect the growth of plants?

Valster, A.H. and Hepler, P.K. (1997) Caffeine inhibition of cytokinesis: 
effect on the phragmoplast cytoskeleton in living Tradescantia stamen hair 
cells. Protoplasma 196, 155-166.


Wisconsin Fast Plants