Study On Genetic Diversity And Reproduction Type Of Dateplum Persimmon (Diospyros Lotus)

On the base of phenological observation,24dateplum persimmon （Diospyros lotus L.）genetic resources were observed morphologically; according to the method of linkagebetween groups, cluster analysis was carried out by PASW statistics18.0software.Relationship and genetic diversity of46dateplum persimmon genetic resources have beenresearched by SCoT molecule marker technology combined with clustering analysis; discussthe facultative apomixis phenomenon in the dateplum persimmon by bagging technology andSCoT molecule marker technology; confirm chromosome ploidy of dateplum persimmongenetic resources by flow cytometry.The main results were highlighted as follows：1.21morphological traits of24dateplum accessions preserved in the National FieldGenebank for Persimmon in Northwest Agriculture&Forestry University were observed.According to the method of linkage between groups, cluster analysis was carried out byPASW statistics18.0software.24dateplum accessions could be divided into5types while theaverage Euclidean distance was10. Group, Group Ⅱ, Group Ⅲ, Group Ⅳ, and GroupⅤ,including8(which could be further grouped into two sub-clusters),3,10,2and1accessions,respectively. Different degrees of diversity exhibited in different traits. The most obviousvariation coefficient, which reached169.40%, was of the rust of fruit surface, then seed’sshape (66.26%). The smallest variation coefficient was of the sepal size (13.67%). Thehighest diversity index of the16qualitative characters was in seed plumpness (1.908), whilethe lowest one in fruit shape (0.547); The highest diversity index of the5quantitativecharacters was in seed number per fruit (0.687), and the lowest one in distance between thetop1and top2buds (0.438).2. SCoT-PCR system of dateplum persimmon was established and optimized accordingto the SCoT-PCR characters of dateplum persimmon.3. Cluster analysis was undertaken based on the genetic distance which was calculatedby similarity coefficient of46varieties. Cluster analysis using by UPGMA method coulddivide46dateplum accessions into6groups when the genetic distances was0.53, meanwhilewe analyze the genetic relationship of different varieties and groups.4. The facultative apomictic genetic characteristics of dateplum persimmon were confirmed by bagging technology and SCoT molecule marker technology. These resultsprovide essential information for breeding and origin mechanism of apomixes.5. Relative content of DNA from dateplum persimmon leaves were detected by flowcytometry. The results showed that Yemaoshi with Staminate red flower were tetraploid plant;ShaHong seedless dateplum persimmon were diploid; Zhejiang persimmon wre diploid; Wupersimmon were sextuploid; Bishan persimmon were tetraploid plant.