Evaluation of Photomixotrophic Technique and Several Carbohydrate Sources as Affecting Banana Micropropagation

Photomixotrophic technique refers to cell employment of endogenous and exogenous carbohydrate sources to obtain energy in the presence of CO2 enrichment. This investigation aimed to evaluate the photomixotrophic technique as a combination between various concentrations of CO2 enrichment, and several types of carbohydrate sources (sucrose, fructose, glucose) at different concentrations on growth parameters of banana among all micropropagation stages. In multiplication, photomixotrophic technique enhanced the growth parameters, as the most effective carbohydrate was sucrose (20g/l with 600ppm CO2 for shoot number and 10g/l with 900ppm CO2 for shoot length), which may belong to its permeability through cell membrane and its gradually consumption. In rooting, presence of CO2 enrichment around the culture containers atmosphere may reduce the need of sucrose in culture medium to 1% instead of 3% (the most used in tissue culture medium). This result led to augment the vigor of the produced plantlets and configure them to tolerate the shock of acclimatization by enhancing photosynthesis and adjusting respiration and transpiration systems through activation of stomata functions and wax synthesis. In acclimatization, most growth parameters especially survival number and percentage were motivated by photomixotrophic at 900 or 1200ppm CO2 and all sucrose concentrations. Indeed, photomixotrophic technique may decrease the exogenous need of carbohydrate with motivating the plant growth parameters of banana.