The effects of alternating red and blue light on young tomato plants (in collaboration with the Institute of Urban Agriculture, China)

The experiment will be conducted in the Institute of Urban Agriculture, CAAS (Chengdu, China).

Leaves under monochromatic red light suffered abnormal photosynthetic functioning including a low maximum quantum yield (Fv/Fm), unresponsive stomatal conductance (gs), and a low photosynthetic capacity (Amax), which can be avoided by adding only 7% blue light (Hogewoning et al., 2010). Besides, these red-light syndromes can be partly recovered by supplementing blue light (Trouwborst et al., 2016). Similarly, monochromatic blue light led to a lower photosynthetic capacity in leaves than mixed red and blue light. Besides, the photosynthetic capacity increased with increasing blue light percentage from 7% to 50% in mixed red and blue light, associated with a rise of leaf thickness, chlorophyll content, and stomatal conductance (Hogewoning et al., 2010). Thus, mixed red and blue light is commonly used in research and practice. Currently, some papers report that the different red and blue light pattterns play a role in improving plant growth. This project will follow the previous studies and determine the effect of different red and blue light patterns and ratios on plant growth and carbohydrate accumulation.

Used skills

• Climate chamber experiments
• Plant growth measurements (e.g. fresh and dry weight, petiole length, pictures)
• Data analysis
• Data visualization

Interested in doing a BSc or MSc thesis at HPP? Please contact the HPP student coordinator Katharina Hanika.