กายวิภาคศาสตร์เปรียบเทียบใบ และสัณฐานวิทยาเรณูของพืชวงศ์มะดูกในประเทศไทย

Abstract

The comparative anatomy of leaf by peeling method and paraffin technique of leaf blade and petiole in 13 genera and 23 species of Celastraceae in Thailand are found as following: All of species are hairless on epidermis. The shapes of epidermal cells are polygonal or jigsaw-like. The anticlinal walls are straight, and undulate. Stomatal types compose of leterocytic, paracytic, cyclocytic and anisocytic type are observed in this study. In addition, types of inclusion are prismatic crystal, druse crystal and dark red staining inclusions. Some species were found secretory cavity. Stomatal density varies 193.4-1,038.7 per mm2. Stomatal length ranges from 8.47 to 24.53 micrometre. Stomatal index is 5.41 to 19.89%. Type of vascular bundle has collateral and amphicribal. The number of vascular bundles in midrib has 1-12 bundles and 1-3 small vascular bundles in some species. There're 6 types of shape of vascular bundle. Lamina were founded 1 vascular bundle in all species including 3 types of shape of vascular bundle. While, petiole composes of 1-10 vascular bundle, 1-7 small vascular bundle in some species and 7 types of shapes of vascular bundle in petiole. Most of species were found sclerenchyma surrounding continue or discontinue of vascular bundle. In addition, the characteristics that can be used to identify for species level are shape and anticlinal wall in the surface tissues such as, the type of stomata, crystal, number and shape of vascular bundles in midrib and shape of vascular bundle in petiole. The pollen morphology of 13 genera 31 species in Celastraceae in Thailand were observed by using light and scanning electron microscopes. The common characters of pollen are monad (except tetrads in Lophopetalum), isopolar and radial symmetry. The size of the pollens is from very small (less than 10 micrometers) to medium (25-50 micrometers). The shape of pollens has 5 types such as suboblate, oblate spheroidal, oblate, subprolate and prolate spheroidal. Pollen aperture are 3-colporate, 3-porate and 4-colporate. Four differentiated exine sculpturing patterns are observed: reticulate, striate, striato-reticulate and punctate. Moreover, the result indicates that the types of pollen, aperture and exine sculpturing data provide taxonomic supportive evidence for classifying some generic level, while shape, size and exine sculpturing data provide the useful characteristic of delimitation of the species level in Euonymus, Glyptopetalum, Gymnosporia, Loeseneriella, Lophopetalum, Microtropis and Salacia.