Investigating the effect of far-red light on leaf photosynthesis to increase production

Application of light-emitting diode technology has opened opportunities to optimize light spectrum for crop production greenhouses and vertical farms, but also pointed to interesting aspects of far red light on photosynthesis in the field and natural light environments. As one of the very few labs in the world the HPP-CSA photosynthesis lab has a range of advanced measuring methods/techniques in house as well as plant growth facilities with simulated solar light to investigate the role of far-red during leaf development, as well as instantaneous photosynthesis at leaf and plant level.
Our recent research on tomato has shown that in addition to photosynthetically active radiation, far-red light has to enhance leaf photosynthesis driven by PAR wavelengths. But this enhancement differs per PAR wavelength, which is important for future LED-light applications. Additionally, far-red induced enhancement of photosynthesis of leaves grown in sunlight was much lower than of leaves grown in shade light, and the presence of far-red in growth light has a strong influence on the maximal photosynthetic capacity and mesophyll conductance for CO2-difusion, but in an intensity-dependent way. These results all point to an important regulatory role of far-red on the photosynthetic efficiency of leaves. How this interaction of light intensity and far red physiologically works and how fast leaves acclimate is not known, while this knowledge is essential for further optimalisation of artificial light and energy-use reduction in horticulture
In our ongoing research on far-red in relation to improving photosynthetic efficiency of crop plants we currently have space for one or two students with interest in cutting-edge photosynthesis research (MSC-thesis and Research available), plant physiology and the skills to work with advanced measuring techniques and data-analysis.
The following projects involve combinations of measurements of chlorophyll fluorescence/other optical techniques, gas-exchange and stable C-isotope fractionation during gas-exchange.

  1. Understanding costs and benefits of far-red in leaf photosynthesis: interaction between acclimation to far-red/light intensity, momentaneous leaf photosynthesis during leaf aging on their maximal photosynthetic capacity and mesophyll conductance.
  2. Understanding costs and benefits of far-red in leaf photosynthesis: impact of short periods of sunlight intensity-spectra on shade-light acclimated leaves such as occurs in tomato greenhouse crop.
  3. Understanding costs and benefits of far-red in leaf photosynthesis: are towards shade acclimated leaves an underestimated factor for whole plant photosynthesis? Research with focus on leaf to plant scaling in photosynthesis measurements.
  4. As above, but with more focus the role of on nitrogen

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