Study On Morphologies Of Seeds And Leaf Epidermis With Numerical Taxonomic Of Rosa L. In China

Based on specimens of genus Rosa L. collected in China, the classification and stysterm evolution of Rosa L. were studied, concentrating on the micromorphology of seeds and leaf epidermis. Method of numerical taxonomy was also applied in this paper. The results are listed as follows:(1) The seeds of the genus are diverse in shape and most of the seeds in the genus are oval, as well small part of the seed is widely oval with rectangularly circular or elliptic; The seed of color is mainly brown of irregularity and size has smaller difference in each group under light microscope, in addition, the macroscopic morphological characteristics of the seeds are consistent in the group. Seed coat patterns are mainly reticulate type observed under the scanning electron microscope, and negative reticulate type or relatively flat type.There are differences in the seed coat patterns, but they have a certain stability in the group. The characteristics of seed can be used as the basis for the classification of the species of genus Rosa L.(2) The upper and lower epidermal cells of most species in the genus are polygonal. All of 41 plants of the Subgen.Rosa are hypostomatic and the whole observed species of the Subgen.Rosa are unilaminar outer stomatal rim except for amphistomatic R.berberifolia Pall. belong Subgen. Hulthemia(Dumort.) Focke; Most stomata type are anomocytic,with some others anomotetracytic or paratetracytic,as well as stomatal shape elliptic,widely elliptic or oblong elliptic; Periclinal walls of most epidermal cells of the genus are sunken and some fraction of epidermal cells are bulging under the scanning electron microscope.Two kinds of trichomes could be distinguished in this study,They are pubescence or glandular in Rosa L.,and most species have long pubescence or short pube scence,as well a small number of plants are glabrous.Bases of most single pubescence are no specialization and surrounded by ordinary epidermal cells,only a very small group of species are surrounded by specialized radial cells.The cuticular wax ornamenta tion are nearly smooth,papillose or granulate,or with layer of small processes and flake-like waxy layer.(3) Traits clutering analysis results showed that the distribution of 43 traits choosen herein is sparse and the correlation between traits is not strong. It is clear that the variation of morphological traits, to some extent, is independent in the process of evolution in the genus Rosa L.In conclusion, the results of morphology of seeds and leaf epidermis, plus the numerical taxonomic analyses, can offer reference for specific identification, and provide data to systematic evolution studies on Rosa L.