The effect of oriented irradiance on plant growth and development – experiments for teaching phototropism in plant biology at high schools
The present paper summarizes theoretical background, practical notes and design of two experiments on plant phototropism to be conducted at high schools. Theoretical introduction describes different types of plant tropisms, e.g. gravitropism, heliotropism and phototropism, and different types of nastic movements not directionally oriented. Phototropism is a type of plant growth reaction oriented towards or against the direction of the source of irradiation, called positive phototropism or negative phototropism, respectively. The Experiment 1 is aimed at the effect of the different irradiation wavelength on the growth of plant shoot of Lepidium sativum. It is demonstrated there that blue light and, thus, blue photoreceptors are determining stem positive phototropic reaction. The use of LED light source to induce irradiation of a narrow wavelength is recommended. The Experiment 2 then demonstrates negative phototropism of plant roots. An important part constitutes the experience gained during the design, accomplishment and verification process for the presented experimentation. Both experiments were designed in cost-effective way for application of scientific approaches and protocols at high schools.
plant biology, oriented source of irradation, photomorphogenesis, phototropism, high school, experiments, teaching, light
Albrechtová, J., Sedlecký, L., & Čížková V. (2017). Fotomorfogeneze – teoretické základy pro výuku biologie rostlin na školách. Biologie, chemie, zeměpis, 26/4: 26-37. https://doi.org/10.14712/25337556.2017.4.3
Briggs, W. R. (2014). Phototropism: some history, some puzzles, and a look ahead. Plant Physiology, 164(1), 13-23. https://doi.org/10.1104/pp.113.230573
Celaya, B., & Liscum, E. (2005). Phototropins and associated signaling: Providing the power of movement to higher plants. Photochemistry and Photobiology, 81, 73-80. https://doi.org/10.1562/2004-08-22-IR-282.1
Darwin, C., & Darwin, F. (1880). The Power of Movement in Plants (London: John Murray). Sekundární citace z Rivière et al. (2017).
Davis, P. A., & Burns, C. (2016). Photobiology in protected horticulture. Food and Energy Security, 5(4), 223-238. https://doi.org/10.1146/annurev-arplant-050312-120221
Kolář, J. (2013). Jak se slunečnice otáčejí za Sluncem? A pohybují se i v noci? Zdroj: www.prirodovedci.cz: https://www.prirodovedci.cz/zeptejte-se-prirodovedcu/403
Rivière, M., Derr, J., & Douady, S. (2017). Motions of leaves and stems, from growth to potential use. Physical Biology. https://doi.org/10.1088/1478-3975/aa5945
Sedlecký, L. (2013). Fotomorfogeneze: vliv světla na procesy vývoje rostlin ve výuce biologie na školách (diplomová práce). Nepublikováno. Přírodovědecká fakulta Univerzity Karlovy, Praha. https://is.cuni.cz/webapps/zzp/download/120139034
Takemiya, A., Inoue, S. I., Doi, M., Kinoshita, T. & Shimazaki, K. I. (2005). Phototropins promote plant growth in response to blue light in low light environments. The Plant Cell, 17(4), 1120-1127. https://doi.org/10.1105/tpc.104.030049