Indoor Plant Production Systems - Effects of Light Quality on Light Transmission Ratio of Rice Canopies
- Publication Type
- Contribution to conference
- Authors
- Schmierer, M., Asch, F. Brueck, H.
- Year of publication
- 2013
- Published in
- Agricultural development within the rural-urban continuum
- Editor
- Tielkes, E.
- Pubisher
- Cuvillier Verlag , Göttingen
- Page (from - to)
- 378
- Conference name
- Tropentag 2013
- Conference location
- Hohenheim
Climate change related constraints to plant production such as extreme weather events,pests, and soil erosion are stimulating discussions on the feasibility of indoor plantproduction systems. Concepts are being considered that range from small scale unitsfor specific biochemicals (biofarming) to industrial scale for production of vegetablesor ornamental plants. Even though many environmental factors are modifiable in suchsystems allowing a high degree of control of the growing conditions of plants, arti-ficial environments are far from meeting plant requirements for optimal growth anddevelopment. For instance, light intensity and light quality are being kept constant in-side a growth chamber for the entire growth cycle despite the fact that light absorptionpatterns will change as a function of interactions between canopy development andstructural components of the growth chamber. Changes in the physical properties ofthe canopy such as leaf area, leaf angle distribution and the appearance of generativeorgans may require adjustments over time in both light quality and light intensity tofully meet the requirements for optimal growth and development of the plantTo investigate these kinetics we measured the light distribution above, inside and be-low a growing rice canopy in a customized growth chamber with specifically devel-oped LED panels. We show that the light transmission ratio of the entire canopydepends on light quality and and on chlorophyll concentration. In addition, we showto what extend the light reflectance and light diffusion properties of the inside of thethe growth chamber affect overall light intensity and influence the illumination oflower canopy layers. These results contribute important aspects to the discussion onthe optimal light quality for plant growth and specification of future lighting solutionssuch as LED or sulfur plasma lamps as here the light properties of the entire canopyare taken into account which affect canopy gross photosynthesis (productivity) andphenological development.