In vitro Establishment and Browning Control of Cinnamon Nodal Explants from Field-Grown Plants (Cinnamomumm verum : Sri Gamunu and Sri vijaya)

Abstract

Cinnamon is cross pollinated species and wide variability has been observed in yield, quality of produce and oil content and other morphological characteristics. Cinnamon is still exclusively seed propagated. However seeds are highly recalcitrant and therefore, viability diminishes rapidly creating problems for bulking and transporting of seeds for large scale production of plant material. Through consistent efforts, a series of elite cinnamon lines have been identified by cinnamon research station with some superior lines which produce high yields of better quality bark, bark oil and leaf oil. Vegetative propagation techniques like rooted stem cuttings have been reported to be used for experimental purposes but has not been applied at commercial nursery scale. Therefore, there is an urgent need to develop rapid and reliable methods of mass propagation for cinnamon to meet the demand for high quality planting material while conserving their genetic superiority Therefore, this study is proposed to develop a reliable in vitro cloning protocol for the commercial scale production of planting material in order to reap the best use of these selected elite cinnamon lines for local cinnamon industry. As the first step, the objective of present study was to control of browning and contaminations in establishing of nodal explants which is crucial for in vitro cloning of cinnamon. Experiments were conducted to find out the best surface sterilization process and control of browning in established cultures. Results revealed that 25% Clorox for 10 minutes followed by shaking in ethanol for 30 seconds gave highest non contamination (60%) in nodal explants. Correct maturity stage played a major role in controlling browning along with anti-oxidant or absorbent in the establishment medium. Five weeks after bud emergence (stage 6) were identified as the correct maturity stage for 100% non-brown cultures with ascorbic acid (0.15g L 1) or activated charcoal (lg L 1). Established cultures were inoculated in hormone medium for shoot multiplication.