Photosynthetic efficiency and in vitro growth of Celastrus paniculatus Willd. under varied concentrations of CO2

Abstract

Introduction: Celastrus paniculatus (family: Celastraceae) is a woody climbing shrub valued for its immense medicinal properties contained in its various plant parts. Over-exploitation and poor natural regeneration either by seed or other method/s have resulted into depleting population of C. paniculatus in natural habitats in India. Novel approaches such as liquid culture media and photoautotrophic multiplication of shoots on sugar-free media has proved useful to obtain photosynthetically active micropropagated plantlets. Methods: The shoot cultures of C. paniculatus were multiplied on sucrose containing and sucrose-free semi-solid and liquid media. The cultures were further incubated under various concentrations of carbon dioxide (0.0 to 40.0 gm-3). The assessment of chlorophyll fluorescence parameters (F o , F m , F' m , F t , F v /F m and ΦPS2) under similar conditions was undertaken. Results: It was observed that CO 2 enrichment favored shoot multiplication and elongation and biomass production in sucrose supplemented medium. CO 2 (10.0 gm-3) along with sucrose (3.0%), recorded maximum growth on semi-solid and liquid media. The valuation of F o , F m , F' m , F t , F v /F m and ΦPS2 revealed that an increase in the concentration of CO 2 resulted in a decline in all the parameters especially the F v / F m and ΦPS2. On the contrary, withdrawal of sucrose from the medium under CO 2 enriched conditions resulted in a moderate growth rate and biomass production. However, F v /F m and ΦPS2 were considerably improved in shoot cultures incubated under elevated concentrations of CO 2 (10.0 gm-3) without sucrose in the medium indicating their photoautotrophic growth. Conclusion: Liquid medium proved to be superior for overall growth and biomass production over its semi-solid counterparts. The observations of photochemical efficiency in shoot cultures grown on liquid medium were at par with their semi-solid counterparts indicating no adverse effects such as hyperhydricity.

The Effect of Sucrose Supplementation on the Micropropagation of Salix viminalis L. Shoots in Semisolid Medium and Temporary Immersion Bioreactors

“…[30], Celastrus paniculatus Wall. [31] and Vernonia condensata Baker [32] supplemented with conventional sugar concentrations and allowed the growth of shoots cultured with low sucrose or even without any supplementary carbohydrate, as reported for Paulownia fortunei (Seem.) Hemsl.…”

Low CO2 Levels Are Detrimental for In Vitro Plantlets through Disturbance of Photosynthetic Functionality and Accumulation of Reactive Oxygen Species

“…However, it has been confirmed that removal of the two main inputs of photosynthesis (light and CO 2 ) are detrimental for production of plants in vitro [6]. In accordance, CO 2 enrichment in vitro increased the shoot growth and multiplication rate in Celastrus paniculatus [14]. In the course of CO 2 starvation, all endogenous electron acceptors become reduced, leaving oxygen as the main available electron acceptor.…”