Genetic diversity cost effective micropropagation and ex vitro establishment of two Himalayan Orchids

Abstract

newlineOrchids are charismatic and cosmopolitan group of plants that hold a high position in the floriculture and horticulture market. These have been widely utilized as ornamentals, medicinal and source of edible products. Uttarakhand is regarded as an orchid hotspot with rich biodiversity owing to its topographical and climatic features. This study is focused on the genetic diversity, cost-effective micropropagation and ex vitro establishment of two important Himalayan orchids, Aerides multiflora Roxb. and Rhynchostylis retusa (L.) Blume, endemic to Uttarakhand. Both the orchid species are epiphytic in nature and are widely used in the traditional system of medicine for treatment of several disorders. Exploitation of both the species for ornamental or/and medicinal purposes puts an immense pressure on the wild populations. The declination of number, and reduced population size of both the species in their natural habitat can be viewed as matter of concern, which prompted this investigation. In this study, data have been generated for both, A. multiflora and R. retusa, on the taxonomic identification, genetic diversity, development of micropropagation protocols with focus on cost reduction for propagation, and optimization of conditions for ex vitro survival of the regenerants to aid reintroduction into wild. newlineDNA barcoding has been effectively used for molecular taxonomic identification especially in orchids. The study confirms the reliability of matK and rbcL markers for species-specific identification of both the orchids. For further estimation of genetic diversity, eight populations of A. multiflora and R. retusa, collected from different locations in Uttarakhand were analyzed using ISSR markers. The average polymorphism recorded in the study was 38.09% in case of A. multiflora and 64.54% in R. retusa. Clustering analysis for both the species revealed that samples collected from sites with similar geographical location and elevation were genetically related. Another key observation was the sub-clusterin