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Based on morphology, the species status and taxonomic affinities of three species of Tinospora ( T. cordifolia, T. sinensis, and T. crispa) with ranges in India, have been questioned . To evaluate species delimitation and population structure among 40 accessions of the three species , a relatively new marker, cytochrome P450, was used. Five out of nine primers generated polymorphisms with 39 out of 47 bands polymorphic. The P450 binary data, when analyzed using distance methods, strongly supported the monophyly of each Indian species and were congruent with previous RAPD work. To further investigate the status of these species, we combined P450 and RAPD data. The resulting unrooted phylogram highly supports the monophyly of each species but with little population structure within each species. To understand the phylogenetic placement of the three Indian Tinospora species within Menispermaceae, chloroplast atpB and rbcL sequence data for a large sampling of the family were analyzed using likelihood and parsimony methods. The resulting phylogenies highly support the Indian Tinospora species as part of a clade (expanded Tinosporeae), consisting of diverse Menispermaceae from around the world. The three Indian species are monophyletic and are most closely related to Tinospora species from Australia ( T. esiangkara and T. smilacina). [ABSTRACT FROM AUTHOR]

The phylogenetic relationships among the three species of Tinospora found in India are poorly understood. Morphology does not fully help to resolve the phylogeny and therefore a fast approach using molecular analysis was explored. Two molecular approaches viz Random Amplified Polymorphic DNA (RAPD) assay and restriction digestion of ITS1-5.8S-ITS2 rDNA (PCR-RFLP) were used to evaluate the genetic similarities between 40 different accessions belonging to three species. Of the 38 random primers used only six generated the polymorphism, while as three out of 11 restriction enzymes used gave polymorphic restriction patterns. The average proportion of polymorphic markers across primers was 95%, however restriction endonucleases showed 92% polymorphism. RAPD alone was found suitable for the species diversions. In contrast PCR- RFLP showed bias in detecting exact species variation. The correlation between the two markers was performed by Jaccard's coefficient of similarity. A significant (r= 0.574) but not very high correlation was obtained. Further to authenticate the results obtained by two markers, sequence analysis of ITS region of ribosomal DNA (ITS1 and ITS2, including 5.8S rDNA) was performed. Three independent clones of each species T. cordifolia, T. malabarica and T. crispa were sequenced. Phylogenetic relationship inferred from ITS sequences is in agreement with RAPD data. [ABSTRACT FROM AUTHOR]