Relationship Between Environment And Morphology And Genetic Diversity Of Bryophytes

Bryophyte is a big group in plant and very important to the nature. Bryophytes are sensitive to the variation of environment. Being a indicator of environment variation, it is very important to study the relationship between bryophytes and environment. In the present paper, the studies were carried out among and within species. Furthermore, some preparatory experiments based on molecular markers were also done for studying the relationship between genetic diversity of bryophytes and environment.1. Studies on the anatomical structure of leaves in four bryophytesThe anatomical structures of Bryoerythrophyllum inaequalifolium (Tayl.) Zand., Polytrichastrum formosum (Hedw.) G. Sm., Bartramia pomiformis Hedw. and Grimmia macrotheca Mitt, from Rangtang, Sichuan were observed and analysed by means of paraffin wax section. Though leaves of the four bryophytes exist similar structure in both blades with one cell-layer and costae with several cell-layers, the thickness and cell density in the both aspects are evidently different. In addition, costae of B. pomiformis have cell differentiation and more complex construction than that of G. macrotheca, of which cells scarcely differentiated; the ventral surface of leaves of P. formosum is covered with lamellae; the surface of leaf cells of B. inaequalifolium has fine papillae; the leaf cell walls of G. macrotheca are thickened.2. Relationship between environment and anatomical structure of leaves inRhodobryum roseum (Weis.) Limpr.The anatomical structures of R. roseum from seven populations were measured and analyzed by means of paraffin wax section, scan and digitization in computer. The thickness of leaves and costae increased, while the area and the cell density of leaves decreased along with elevation growing. The anatomical structures of leaves under shruberry were evidently different form that of under arbor. The variation under shruberry was similar to high elevation. It was suggested that the variation of leaves in R. roseum was associated closely with environment and the effect of micro-environment was especially severe. Those variations in R. roseum maybe represented enhancement of tolerance to extreme environment such as drought and cold.3. Studies on genetic diversity of Rhodobryum roseum (Weis.) Limpr. and Rhodobryum giganteum (Hook.) Par.The peroxidase(POD) isozyme and DNA extration method were studied in Rhodobryum. The diversity of POD isozyme in Rhodobryum was very low and somewhat affected by environment. R. giganteum with specific POD strip can be distinguished with R. roseum. On other hand, a fast method was used to extract the DNA of R. giganteum. The purity of the extrated DNA was high and can be used as templates for PCR amplification. Four RAPD primers and thirteen ISSR primers were filtered to R. giganteum. Based on the primary studies, it was considered that ISSR markers were better than RAPD to reveal the genetic diversity of Rhodobryum.As mentioned above, environment is more effective to morphology of bryophytes than genetic diversity.