Integrative approaches of morphological and molecular characterisation in Cnidoscolus aconitifolius (Mill.) I.M. Johnst

Integrative approaches of morphological and molecular characterisation of Cnidoscolus aconitifolius (Mill.) I.M. Johnst., involved both the evaluation of its phenotypic traits and DNA barcoding using rbcL, matK, and ITS markers for the accurate identification. Morphological characters like palmately lobed leaves, absence of spines, long petiole and a perennial shrub habit revealed the studied plant is the most domesticated variety of Cnidoscolus aconitifolius (chayamansa), which was originally introduced from Mexico to Kerala. However, distinct phenotypic variations exist between the Chayamansa in Kerala and Mexico, due to the environmental adaptation, artificial selection and vegetative propagation. So, to confirm the taxonomic identity, molecular characterisation was conducted. Phylogenetic analysis was done with the Neighbour-joining method trees by using the sample sequence and the sequences retrieved from Genbank. The rbcL and matK phylogenetic trees help with the genus and species-level identification. The ITS phylogenetic tree exhibited higher resolution, clearly distinguishing C. aconitifolius from closely related taxa within the genus Cnidoscolus, with strong bootstrap support indicating its superior discriminative capability. The integrative effect of morphological and molecular data helped to confirm the studied plant as C. aconitifolius (Chayamansa). The effectiveness of the ITS marker showed high efficiency for species-level resolution as well as high discriminatory power. So, combining the effects of morphological and molecular methods is very precise for species authentication. These findings establish a reliable and fundamental taxonomic framework for future pharmacognostic and bioactivity investigations on C. aconitifolius and its varieties.