|MadSci Network: Botany
If you want a project that deals with both plant hormones and plant tropisms, that narrows your choices severely. You have a lot more choices if you just focus on plant hormones or just on plant tropisms. One of the few projects you could do would be some of the early phototropism experiments with grass seedling coleoptiles. These experiments by Charles Darwin, Fritz Went, Boyson-Jensen and others are described in college Botany and Plant Physiology textbooks. They are simple experiments but require some precision because they deal with small seedlings. One of the main phototropism-hormone experiments was to cut off the coleoptile tip and place it on agar, allowing hormones to diffuse into the agar. The agar was cut into a small block and placed back on one half of the cut tip of the coleoptile to see of the hormone could induce bending. You could also try adding different hormones to the agar or different amounts of auxin. Other types of coleoptile phototropism experiment are 1. use mica plates to block hormone diffusion down one side of the coleoptile or laterally from one half of the coleoptile to another 2. use foil caps to block light to coleoptile tip 3. use different colors of light to determine which color(s) activate phototropism You can cheaply and simply estimate the concentration of auxin you collect in agar blocks using a bioassay such as the Avena coleoptile curvature test. References Phototropism experiments Phototropism Part I: Light and auxin Went's Avena Coleoptile Curvature Test Plant Hormones - Auxin The Avena Test - a Bioassay
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