In vitro growth and shoot multiplication in Terminalia bellerica Roxb. under controlled carbon dioxide environment

Abstract

The shoot cultures of Terminalia bellerica Roxb. were grown on Murashige and Skoog’s medium containing 1.5 mg l ⁻¹ BAP (6- benzyl aminopurine), and supplemented with or without sucrose (3 %). A range of CO₂ concentrations (0.0, 0.6, 10, 40 g⁻³) was provided in small acrylic chambers by using different concentrations and combinations of NaHCO₃ (sodium bicarbonate), Na₂CO₃ (sodium carbonate), KHCO₃ (potassium bicarbonate) and K₂CO₃ (potassium carbonate). To obtain a CO₂-free environment, a saturated solution of 10 % of KOH (potassium hydroxide) was kept in the chamber. Complete absence of carbon source caused death of shoots within 20 days. Under controlled and enriched CO2, the shoots grew fully photoautotropically on sucrose-free medium. The growth of cultures was better with carbon dioxide (40 g⁻³) than sucrose (3%) in the medium. Maximum number of shoots, number of leaves per cluster, fresh and dry weight and chlorophyll contents were recorded when both sucrose and CO₂ (40 g⁻³) were provided to the culture.