THE GROWTH AND CO₂ EXCHANGE OF CYMBIDIUM PROTOCORM-LIKE BODIES RELATED TO SUGAR IN THE CULTURE MEDIUM

Cymbidium protocorm-like bodies (PLB) Melody Fair ‘Marilyn Monroe’ were cultured on an MS medium containing 2% sucrose and 0.6, 0.8, or 1.0% agar under continuous lighting.
Rates of dry weight increase and sugar uptake were the highest in the lowest agar concentrations and the lowest in the highest agar concentrations.
The percent of dry matter peaked in the initial period of culture, probably due to the high molar concentration of sugars in the medium.
In all the concentrations of agar, the net photosynthetic rate per dry weight increased from Day 20 to Day 60, while the dark respiration rate decreased for the culture.
The surplus sugar uptake might lead to a dry matter increase rather than an extra dark respiration.
In all the concentrations of agar, the agar gel near the PLB contained less sugar than the other parts of the medium, suggesting that low diffusibility of sugars through the agar gel is a limiting factor in the sugar uptake.

Environmental Effects and their Control in Plant Tissue Culture

N. Ogasawara, S. Haneishi, C. Suzuki, H. Takagi

agar concentration, CO₂ exchange, Cymbidium, protocorm-like body, sugar uptake

https://doi.org/10.17660/ActaHortic.1995.393.8