Low-Cost Gelling Agent in Tissue Culture Technology for the Orchid Regeneration

Abstract

Orchid is one of the most important cut flowers, grown in Sri Lanka for export and local market. One of the majors constrains in expanding the orchid cultivation is limited supply of quality planting materials. Micropropagation techniques can be successfully applied for mass propagation of orchids by the micropropagation is expensive thus increase the cost of production. Therefore, this research was undertaken for replacement of expensive agar for in vitro subculturing of Cattaleya seedlings. Two-month-old Cattleya seedlings were subcultures on Murashige and Skoog media (MS) as basal media. As gelling agents' sago, semolina, corn flour, semolina + agar, and corn flour + agar was used. Control treatment was carried out with agar. Cultures were maintained inside the culture room. Number of leaves, number of roots, leaf length, leaf width and percentage of contaminations were recorded at four-week intervals. Sago and semolina + agar showed higher performance and low contamination percentage as alternative gelling agent in the MS media. The results of this study propose that sago, semolina, and corn flour can be used as an alternative gelling agent in MS media for subculture practices of orchids. Keywords: alternative gelling agent, alternative water source, Orchid subculture INTRODUCTION Micropropagation is the practice of rapidly multiplying stock plant material to produce many progenies plant under specific control environment condition. It is used to multiply novel plants, such as those that have been genetically modified o r b r e d t h r o u g h conventional plant breeding method. It is also used to provide enough plantlets from a stock plant which does not produce seeds or does not respond well to vegetative reproduction. Using the appropriate growing conditions for each explants type, plants can be induced to rapidly produce new shoots and new roots with the addition of suitable hormones. These plantlets can also be divided, usually at the shoot stage, to produce large numbers of new plantlets. The new plants can then be placed in soil and grown in the normal manner.