PHOTOSYNTHESIS IN VITRO – ON THE FACTORS REGULATING CO₂ ASSIMILATION IN MICROPROPAGATION SYSTEMS

Poor photosynthetic activity of plantlets cultured in vitro is considered one of the major limiting factors for the improvement of micropropagation efficiency and acclimatization success.

Photosynthesis (Pn) of tissue-cultured plantlets is variable and affected by many factors.
Large differences in Pn of chlorophyllous cultures can be explained in part by the difficulty of measuring gas exchange under representative conditions.
They can also be explained by the different explant types and sizes and by the stage of growth.
Finally, environmental conditions like CO₂ and O₂ concentration, light quality, and presence of exogenous sugars in the medium will have profound impact on the photosynthetic capacity.
Based on the available scientific literature, we can propose a model to explain how in vitro culture conditions affect plantlets sink/source relationships, deactivate Rubisco and reduce Pn.

Environmental Effects and their Control in Plant Tissue Culture

Y. Desjardins

acclimatization, gas exchange, light, PEPC, photoautotrophy, Rubisco, sucrose, tissue-culture

https://doi.org/10.17660/ActaHortic.1995.393.5