|MadSci Network: Botany|
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
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