Effects of CO2 Enrichment and Sucrose Concentration Under High Photon Fluxes on Plantlet Growth of Carnation (Dianthus caryophyllus L.) in Tissue Culture During the Preparation Stage

Abstract

Explants of tissue-cultured carnation (Dianthus caryophyllus L.) plantlets were cultured in preparation for growth during the acclimatization stage. Plantlets werecultured in glass test tubes with plastic formed caps in a room with CO2 concentration of 1000-1500vpm and a photosynthetic photon flux of 150μmol m-2s-1 (400-700nm). The effects of the sucrose concentration in the medium on the plantlet growth were also examined under the above mentioned culture conditions.The plantlet growth was promoted, to a large extent, by CO2 enrichment under high photon flux. The order of largest to smallest of fresh and dry weight increases of the plantlets during the culture was CO2 enriched treatment with 1% sucrose, CO2 enriched treatment with 0% sucrose, CO2 enriched treatment with 2% sucrose, CO2 nonenriched treatments with 2% sucrose, 1% sucrose, and 0% sucrose. Plantlets grew autotrophically by CO2 enrichment with high photon flux.The net photosynthetic and dark respiration rates of the plantlets and the dry weight decreases in total sugar and nutrient salts in the medium were estimated to explain the differences in the dry weight increase of the plantlets in the various treatments. The implications of the results for developing a new mass propagation system of tissue-cultured plantlets are discussed.