2. Sugar concentration
3. Types of supporting materials
4. Plant growth regulators
5. Nutrient concentration and volume of the medium
6. Water potential
7. Other factors
8. Calculation of osmotic potential and water potential of air
Key words: Hydroponic, nutrient medium, osmotic potential, oxygen concentration, photoautotrophic micropropagation, root zone, supporting material, water potential.
In photoautotrophic micropropagation, plantlets must be grown under appropriate environmental conditions that promote photosynthesis. These conditions should include considerations of not only the aerial (headspace) environment, such as CO2 concentration and photosynthetic photon flux, but also the root zone environment. While controlling the root zone environment is not easy, selection of supporting materials (i.e., replacing agar gel with porous supporting materials) that may create a better root zone environment (i.e., oxygen or nutrient availability) is relatively easy. Without sugar in the medium and with porous supporting materials and liquid medium, the system is more like a small hydroponic system, referred to as "microponics" (Hahn and Lee, 1996). Improvement of root zone environmental control in photoautotrophic micropropagation may well benefit from the expertise and techniques available from hydroponics.
Was this article helpful?