Chemotaxonomic variation in forskolin content and its correlation with ecogeographical factors in natural habitat of Coleus forskohlii Briq. collected from Vidarbha (Maharashtra, India)

Abstract

Phytogeographical variation has an impact on up/down regulation of secondary metabolites in medicinal plants. In the same context, present study was planned to evaluate the variation of forskolin content in Coleus forskohlii from Vidarbha region (Maharashtra), India having different topographical conditions. The chemotypic variation was further correlated with existing soil profile. The data revealed the similarity in morphological, macroscopic and microscopic characters of collected germplasms but there is significant (p<0.05) variation in the content of chemical marker, forskolin. Physicochemical and phytochemical parameters are within the limits of API and serve as standard for commercial utility of samples. NBC-29 (Narkhed) and NBC-31 (Katol) are the first two high forskolin yielding samples, which are clustered together on the basis of forskolin content with similar soil profiles. Furthermore our study demonstrated that there is significant variation in available NPK and micronutrient content within the soil samples and may be reasoned for existing chemotypic variability in samples. Among the micronutrients, manganese and copper exhibit the positive correlation with forskolin.Thus, elite chemotype of C. forskohlii were identified among the samples collected from Vidarbha region and express the relevance of phyto-geographical conditions on the quantity of industrially viable metabolites, forskolin. This aids in site specific exploration of high metabolite yielding accession/samples to meet out the commercial demands and, supply and to promote the agriculture practices of this industrial crop for societal upliftment in area having similar phytogeographical locations.