| Orientalis (Platycladus orientalis (L.) Franco) originates in China.It's germplasm resource is very abundant. Orientalis is an important tree species of afforestation on the rocky barren.According to the reality of the lack of good provenances. The diversity of four orientalis intraspecific populations was analyzed using morphological traits, the genetic diversity and population genetic structure for four geo-ecological groups using principles of molecular systematic and fluorescent-AFLP marker techniques were studied by morphology traits and molecular markers, respectively, in order to provide science evidence for conservation and utilization, to select good provenance and to divid provenance region and to allocate seed.. The main results are as follows:1. The diversity of growth traits of 41 provenances and cones of 21 provenances in 17 provinance of P.orientalis were investigated. The results indicated: There were significant differences among and within provenances. The growth traits have great diversity with the variation coefficient (CV), the range varied from 5.41% to 47.55%. The variation coefficient of branching angle was highest (28.74%), and the one of tree height was lowest; The variation coefficient of seeds was from 4.77% to 47.42%, and the variation coefficient of the seed thickness was the highest, the one of the seed length was the lowset. The variation coefficient of the seed traits is lower than the growth traits, this showed that the genetic stability of seeds is higher.There are siginificantly diversity of the variation coefficient and the relative range in the cone shape and the growth traits, the analysis indicated that there are abundant genetic diversity in the P.orientalis.2. The largest morphological differentiation coefficient of the growth traits among the orientalis was the tree height(Vst= 46.82%), the smallest was the crown(Vst = 20.92%). The average morphological differentiation coefficient of the growth traits was 30.12%, in means that the Vst within the provenance was 69.88%;The range of the morphological differentiation coefficient was from 16.78% to 27.66%. The average of the Vst is 22.92%, the genetic variation among provenance accounted for 77.08% of total variations. This suggested that the variation of morphological traits among provenance of orientalis is much higher than within provenance.3. The result of grey correlative analysis between the growth traits, the seed traits and the latitude, longitude indecates: The correlation of between all traits and the latitude was greater than the longitude, this showed that the morphological diversity of the orientalis mainly came from the latitudinal variation. The typical correlation analysis between the 44 provenances with 8 different traits of the cone showed: the geography variation of oreitalis was a variation that latitude mainly brought on. It's variation mode was two-way variation from latitude and longitude.4.Spatial correlation analysis showed that global moran's I of growth characters is from -0.1878 to 0.1921,the global moran's I of seed is from -0.4842 to 0.7518, most autocorrelation coefficient is not significant,the result showed that presents certain correlation over short distance, while presented spatial uncorrelation or spatial random with distance increases. Global moran's I of DBH is highter than tree height,indicated that variation of DBH is highter than tree height.Local G coefficient of growth characters is from-1.097 to 5.6426,while the seed's is from -2.1899 to 1.9142,and most of them is negative, showed a lack of spatial structure,around provenance is smaller. Local G coefficient of few of northern and southern provenance is 0,they are randomly distributed.5. The semivariance analysis showed that the nugget of DBH growth and height growth were respectively 58.72% and 47.78%, both of which had moderate spatial correlation. While the nugget of branch angle was as high as 90.6%,and the spatial correlation was very weak. When analysis in krige method were performed, the growth Characters of the provenances of platycladus orientalis had certain kinds of spatial structures which presenting a non-random distribution such as progressive change,bi-directional progressive change and irregular patch.Analysis among the provenances P. orientalis also showed a complex pattern that most growth characters seldom have any spatial structure,while A small proportion of the growth characters have spatial structure any way.6. The heritability in, behaved differently between the Pingyin and Zaozhuang sites. At Pingyin site, the heritability in height and DBH was respectively 0.7049~0.9557 and 0.7007~0.8858. At this site, the tree height had higher heritabilities. At Zaozhuang site, the heritability in height and DBH was respectively 0.2684~0.8102 and 0.3262~0.9424. At this site, the DBH had higher heritabilities than the tree height had. Totally, trees in 23 years old had lower heritabilities of both in DBH and tree heigh than young trees had.The correlation analysis between geographical coordinate and annual increment of trees in different forest ages in Platycladus orientalis had the following results: The correlation coefficient between tree height and longitude tended to become weaker with forest got older, while the correlation coefficient between tree height and latitude tended to become stronger with forest got older. Correspondingly, the correlation coefficient between tree DBH and longitude tended to become stronger with forest got older, while the correlation coefficient between DBH and latitude tended to become weaker with forest got older.7.Population genetic structure was studied using fluorescent-AFLP markers on 256 orientalis (P. orientalis (L.) Fr.) accessions collected from the Southern group, the Northern group, the Central of Chian group and the Shandong province group of fluorescent-AFLP markers. The purpose of this study was to determine the genetic structure and genotypic diversity amongst the different provenance of orientalis. The results showed that the average number of polymorphic loci (A) was 100.4, the percentage of polymorphic loci (P) was 46.47% by 8 pairs of EcoR I /MseI (Mse I - a FAM fluorescent marked primer) primers in orientalis of four groups. Analysis for the average number of polymorphic loci (A) and the percentage of polymorphic loci (P) in four orientalis groups indicated that the Sourthern group (A = 102.1,P = 47.28%)> the Northern group (A = 104.2,P = 48.25%)> the Cemtral Chian group (A = 102.1,P = 47.28%)> the Shandong Province group (A =95.4,P = 44.14%); The analysis of diversity and genetic structure from four geo-ecological groups showed that genetic diversity of orientalis provenance in the Southern Group is most abundant, then it is the Northern group; the Northern group and the Shandong Provence group were lowest.8. There was significantly different of genetic diversity among orientalis provenance, the range of is from 1.2622 to 1.6122, is from 1.0983 to 1.2519, the Shannon Index is from 0.1025 to 0.2371. The observed number of alleles (Na), the effective number of alleles (Ne), the Nei's gene diversity (H) and Shannon information index (I) at species level were respectively 1.5311, 1.2022, 0.1305 and 0.2102. The observed number of alleles (Na), the effective number of alleles (Ne), the Nei's gene diversity (H) and Shannon information index (I) at provenances level were respectively 2.000, 1.2406, 0.1605 and 0.2695. Four parameters at species level was high significant higher than at provenances level.At regional level, Nei's gene diversity and Shannon information index (H=0.1434,I = 0.2366)in the Southern group was higher than those in the Northern group (H = 0.1425,I = 0.2305)and in the Central China group(H = 0.1377,I = 0.2283), there were no significant differences; but they were significant higer than those in the Shandong Province group(H = 0.1285,I = 0.2227). The analysis of four population diversity and genetic structure from four provenances showed that genetic diversity of orientalis provenances in the Southern Group was most abundant, there were many heterozygous in the Southern group and the Northern group, the genetic diversity of orientalis provenances in the Shandong Province Group was lower.9. The parameters--genetic differentiation coefficient and gene flow of population genetic structure in orietnalis were analyzed in this study. The genetic diversity at the species level (Ht) was 0.1106, the genetic differentiation coefficient (Gst) among the provenances was 0.2703, This showed that orientalis genetic variation was mainly within the provenances and accounted for 72.97% of total variations, the genetic variation between provenances accounted for 27.03% of total variations. The results from AMOVA analysis showed that the orientalis genetic variation was mainly within the provenances and accounted for 74.86%. The genetic variation of within regional accounted for 11.12%. There was a high level of genetic differentiation at provenances level, and the genetic diversity was mainly at provenances level.10. The gene flow (Nm) was 1.3804 according to the genetic differentiation coefficient between groups (Nm = 1. 3804). This indicated that there are partly gene exchanges among four regional of orientalis. The gene flow (Nm) at regional level was high significant higher than at species level. Analysis for gene flow (Nm) in four orgional groups indicated that the Northern group (Nm = 3.8442) > the Central China group (Nm = 3.3679)> the Southern group (Nm = 2.5390)> the Shandong province group(Nm = 2.1078). This showed that the gene exchange was frequently within the small scale region.11. Nei's genetic identities in 26 orientalis provenances were between 0.8422-0.9919, the average was 0.9380; Genetic distances were between 0.0086~0.1717, the average was 0.0647. It was suggested that there were higher similarity between various geo-ecological groups in orientalis and lower genetic distance.12. The results from UPGMA cluster analysis for 26 provenances showed that all the orientalis could be divided into 5 groups. Almost all provenances from the same population could be clustered into the same group. Three provenances in groupâ… which was call the Southern population came from Ynnan Wenshan, Fujian Nanping, Guizhou Guiyang ; There were 4 provenances found from Northern population in groupâ…¡, which came from Beijing Miyun, Neimenggu Wulashan, Liaoning Chaoyang, and Xinjiang Yili; Totally 3 provenances were clustered in groupâ…¢, Among them, 1 originatel from Sichuan Xichang, 1 from Hubei Jingmen, and the last one is from Henan Qunshan; The groupâ…£came from 7 provinces of the Central Chian, including Gansu Weixian, Jiangsu Tongshan, Shanxi Huangling, Shanxi Shilou, Ningxia Yinchuan, Hebei Yixian, Zaozhuang and Junan of Shandong Province; The groupâ…¤came from Shandong Province, including 8 provenances, they are Feixian provenance, Qufu provenance, Tai'an provenance, Boshan provenance, Anqiu provenance, Pingdu provenance, Pingyin provenance and Liaochen provenance.The Mantel test showed: There was a positive correlation between geographical distance and genetic distance (r=0.288 6,P = 0.093 0). The results from UPGMA cluster analysis for four region groups showed that the Southern group and the Central China group was clustered together firstly and the Northern group were clustered together, at last the Shandong Province group were clustered together. This indicated further that the similarity between the Southern group and the Central China group was highest and genetic relationship was closest.
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