SEM and light microscopic studies in seeds of Hibiscus surattensis L. and phylogenetic attributes in Puducherry region, India

Abstract

ABSTRACT The micro-morphological and scanning electron microscopic (SEM) studies in seeds of Hibiscus surattensis L. has brought out five interesting as well as taxonomically and phylogenetic important traits for the first time. Hibiscus surattensis L. belongs to the family Malvaceae, located at Puducherry region, India. 1. There is a change in the number of locules from pentacarpellary in the ovary during seed maturation and tetra-carpellary after seed maturation in the capsule; 2. Capsules contain both aborted and fully matured seeds recording an average of 4 aborted in 10 capsules; 3. Trichome on seeds consisted of bundle of unicellular finger-like structures, non-glandular and appressed; more importantly hilum is lined with trichomes; 4. Trichomes originate from the outer seed coat as extension/elongation of reticulate-foveate-type seed surface. 5. Embryo was folded occupying both poles and represented approximately the one-third of embryo. Size of the seed, colour, and shape of the seed, surface patterns of seed were examined using SEM. Factors responsible for the production of abortive seeds, functional attributes of non-glandular trichomes and other features are discussed in detail with relevant SEM and microscopic images. Further, phylogenetic importance in elucidating evolutionary clade is also explained. The partial sequence of chloroplast DNA of Hibiscus surattensis L. and neighbourhood joining trees are done for the first time in the study plant growing in India.