Conservation of Vanilla species, in vitro

Abstract

Vanilla(vanilla planifolia) is a crop of great commercial importance as the source of natural vanillin, a major component of flavor industry. The primary gene pool of V. planifolia is narrow and is evidently threatened due to destruction of its natural habitats making the secondary gene pool important as a source of desirable traits especially for resistance to diseases. Many species of vanilla are considered rare and endangered hence an urgent need to conserve them, arises. Effective procedures for micropropagation and in vitro conservation by slow growth in selected species of vanilla, are described. Synthetic seed technology was standardized by encapsulating 3-5 mm in vitro regenerated shoot buds and protocorms in 4% sodium alginate, which could be stored up to 10 months with 80%germination in sterile water at 22±2oC. In vitro conservation technology of vanilla was standardized and shoot cultures could be maintained for more than 1 year without subculture, on slow growth medium, i.e. Murashige and Skoog medium supplemented with 15 g l-1 each of sucrose and mannitol in sealed culture vessels at 22±2oC. These cultures were maintained in vitro for more than 7 years with yearly subculture. The conserved material could be retrieved and multiplied normally in MS medium with 1.0 mg l-1 BA and 0.5 mgl-1 IBA. The in vitro conserved plants showed good growth and development into normal plants. This synseed and in vitro conservation system can be utilized for conservation and exchange of vanilla genetic resources.