| Cerasus discoidea Yü et Li, belong to genus Cerasus (Rosaceae), is a precious endemicspecies of wild cherry in China. However, the utilization and development of wild plant resourcesof this species was irrational, and current related research had not been reported. In order toprotect it, the population variation, community ecology as well as reproductive technology of thisspecies had been studied in this dissertation.The major work and conclusions were as follows:(1) It was shown there was considerable variances in phenotypic characteristics of Cerasusdiscoidea, the main phenotypic variation was leaves and flowers. The quantitative variation ofleaves was not relatively unstable, and great variabilities within populations or betweenpopulations. The quantitative variation of flowers was obvious between groups, C. discoide var.grandiflora C. H. Nan, X. R. Wang et G. G. Tang and C. discoidea var. pendula C. H. Nan, X. R.Wang et G. G. Tang were supported to be new variety of C. discoidea Yü et Li.(2) It's very difficult to extract the total genomic DNA of Cerasus discoidea by CTAB. Toobtain the enough supernatant liquid, we improved the method CTAB method (Silica beads assay)by controlling quality of fresh and dry samples. A suitable SSR-PCR amplification system wascreated through selecting one of the best annealing temperature of19primer for C. discoidea.(3) The species composition, community structure, important value, similarity coefficient,species diversity were analyzed. The results showed that the species composition of C. discoideawas dispersion. The vertical structure of forest form existed little differences, and stratificationwas not obvious, the proportion of regeneration layer of shrub and herb was larger. The importantvalue of tree layer and shrub layer was generally lower, and grew in secondary forests. Thesimilarity of species composition was not high between regions. The species diversity indicesshowed shrub layer> tree layer within communities, the plant species of shrub layer were relativelarger.(4)The populations niche breadth and niche overlap of C. discoidea were higher, and hadbetter environmental adaptability; interspecific survival environment competition was fierce, C.discoidea was freezed out in forest margin or under open forest. The population regeneration wasmainly by asexual suckers, the population age structure was stable developing, because of lots ofsuckers. The number of seedlings were scarce, because of obstacles in sexual update, it was badfor population development of C. discoidea.(5)The banded structure between seed coats and embryos of C. discoidea can protect seed. Itwas identified as endotesta by study in morphology, texture and functions. The two main reasonsof dormancy were the mechanical obstacle of seed coats and germination inhibitor of ABA inseeds. It was advantagous to break dormancy by removing seed coat, gibberellin treatment or lowtemperature stratification. Just cold stratification was suitable for plug seedling and no limits of season changes. After cold stratification(3-5℃)0-30days and then sowing in winter was suitablefor field seedling.(6)The results showed that seed embryo and tender bud were the best appropriate explant fortissue culture. The buds induction could be stimulated with low concentration medium after highconcentration6-BA and the shoots grew stongly on GA3and low concentration agar. The3/4MSculture medium with NAA was suitalbe for the root differentiation. The tissue culture seedlingcan directly transplanted with same tempeture and light condition training,the survival rate was93.8%.
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