Taxonomic importance of seed macro- and micro-morphology in Abelmoschus Medik. (Malvaceae)
27 January 2015
Patil, Pravin; Malik, Surendra; Sutar, Shrikant; Yadav, S. R.; John, Joseph; Bhat, K. V.Seed morphology of Abelmoschus is known to be variable, but variation patterns have never been critically studied. Seed macro- and micro-morphological characters, including seed shape/size, seed coat pattern and trichome density/structure were studied for multiple samples to evaluate their taxonomic significance in order to resolve species boundaries. Among the studied characters seed shape and trichome structure were found to have major taxonomic value and proved to be valuable characters. Two main seed types were present: seeds with deciduous trichome and with persistent trichome. These characters offer significant evidence to distinctness of certain species (A. esculentus, A. moschatus subsp. moschatus, A. moschatus subsp. tuberosus, A. crinitus and A. angulosus). However, A. moschatus subsp. tuberosus should be maintained as a separate species while A. manihot subsp. tetraphyllus var. pungens should be merged in A. angulosus. No significant intraspecific variation was observed in studying samples, except A. esculentus. Seed coat sculpturing play decisive role in morphologically closely related species of Abelmoschus. This study also concludes that LM/SEM techniques can be useful in solving systematic problems and management of Abelmoschus genetic resources.