Assessment of chemotaxonomic relationship among five morphotypes of roselle (Hibiscus sabdariffa L.) using morphological and biochemical markers

Abstract

Despite the reported intraspecific polymorphism among roselle plants, not much has been done to assess their intraspecific diversity in their morphological and biochemical markers. This study employed morphological and biochemical markers to assess the chemotaxonomic relationship among five roselle morphotypes growing in Wukari Local Government Area in Taraba State, Nigeria. The selected morphotypes were collected, identified, and evaluated in the field and laboratory using standard methods. Assessment of qualitative morphological traits revealed that the morphotypes were similar except for stem colour, petal colour, leaf lobe, stem surface, among others. Significant differences (p < 0.05) were observed for all quantitative traits studied with morphotype HS05 showing the highest mean performance for leaf area (214.52cm2), plant height (246.63cm), number of nodes (295), number of branches (10.67). HS01 showed the least mean performance for leaf area (91.34cm2), plant height (60.07cm), number of nodes (145.67), and number of branches (6.00) among others. Phytochemical analysis of calyxes revealed that all the morphotypes contained saponins and alkaloids while steroids were undetected. Analysis of numerical data from chromatographic profiles revealed that HS05 had the highest Paired Affinity value of 85.7% while the highest Group Affinity value of 313.4 was recorded for HS02. Pairwise, HS01 and HS02 as well as HS04 and HS05 clustered together. Results suggest that plant height and number of nodes are important descriptor traits and reveal HS01 and HS05 as the morphotypes with the best prospects for crop improvement. It also reveals HS03 as the morphotype with the most phytochemicals and highlights the potential of chromatography in the chemotaxonomy of intraspecies.