MORPHOLOGICAL AND ANATOMICAL VARIATIONS OF THE SELECTED SPECIES OF OSBECKIA L. (MELASTOMATACEAE)Abstract
Osbeckia L. of Melastomataceae are unique flowering plants showing diversity in their habit and morphological features adapted to their habitats. Limited studies were recorded with the anatomy and morphology of high elevation species. The micromorphology and anatomy of vegetative and reproductive structures of seven species and three varieties of O. aspera, representing diverse habitats such as altitude, availability of water and intensity of sunlight out of the twenty species of Osbeckia reported from India were narrated in the present study. An apparent type of herkogamy noticed in Osbeckia species was also recorded. Herkogamy in this family is an important feature of phylogenetic importance. This aspect of the flowers of Osbeckia appears to represent a special type of herkogamy. The most evident type of herkogamy present in Melastomataceae was represented by flowers that have styles exerted beyond the stamens. Styles and stamens that were about the same length but bent opposite from each other were noticed in some species. Based on the comparison of herkogamy in flowers of many species, it may be concluded that this type of herkogamy was unique in Osbeckia sp. only. The present results showed wide variations among the macromorphological features among the species. Similarly, the stomatal index showed a variation from 16.46 to 36.76 (abaxial side) and 3.98 to 32.19 (adaxial side). Stomata were diacytic to anomocytic type. Epidermal hairs also showed diversity. Further studies are planned for the electron microscopic analysis of pollen, stomata and trichome nature.