Genetic Variation On Growth And Genetic Diversity Of Half-sib Families Among Provenince Of Platanus Occidentalis L. In Eastern China

Relatively systematic research results were reported on genetic variation of Platanus occidentalis L. by means of nursery and sites testing of open pollination families among provenince and RAPD markers in this thesis. Based on the research, superior families of Platanus occidentalis L. on growth were evaluated. The main results are highlighted as follows:1. Based on the investigation of 1-year-old and 2-year-old seedling traits from different families, the results were shown that there were abundant variations within the species of Platanus occidentalis L. and very significant differences among provenince, families on seedling height, basal diameter. There were very significant differences among provenince, families on planting survival rate. Correlations between seedling height and basal diameter were very obvious. Twelve superior families of Platanus occidentalis L. were selected which were No:l,35,17,18,47,26,38,12,41,32,42,ll. No:35,17,18,38,32,42,ll belong to Mississippi valley of Mississippi state(N). No:l,47,12 etc belong to Mississippi valley of Louisiana state(F). No:26,41 etc belong to pearl valley of Mississippi state(B).2. Based on the investigation of four-year-plantation traits from different families, the results were also showed that significant and very significant differences among provenince,families on tree height, diameter at breast height. There were significant and very significant differences among provenance,families on planting survival rate in Dongying Shandong tests. Planting survival rate in Nanyang Henan tests was above 96%. Low temperature in winter was responsible for low planting survival rate in Dongying. There were very significant difference among provenince, families on sites, provenince,families,block, sitesxprovenince,sites families. Growth of Platanus occidentalis L.was owing to genetic factor of provenince and families.condition of planting sites.climatic factor etc. The correlations between growth traits and geographic factors in original regions of provenance were obvious and correlation coefficients were negative. There were high correlation between tree height and diameter at breast height. Correlations between height,diameter at breast height and testing sites' annual average temperature,annual average rainfall,humidity and time of sunlight were significantly obvious. Temperature,rainfall and humidity had large effect on its growth of tree height and diameter at breast height. Results of cluster analysis were in accordance with results of PCA and RAPD markers cluster. Superior half-sib families of Platanus occidentalis L. in Sixian provenance trail were No: 35,11,14,36,34,33,13,5,20,21; In Songjiang trail were No: 1,36,10,9,15,39,16,18,11,30; In Nanyang trail were 14,2,5,6,42,31,19,36,11,25; In Jurong trail were 31,11,3,36,23,41,39,29,24,4; In Dongying trail were 14,3,36,8,6,10,40,18,37,2.Superior individuals in five sites were listed on Tab.3.13.3. Genetic polymorphism of twelve sycamore provenince were studied by RAPD marker. There were 80 polymorphic loci recorded when DNAs were amplifyied with 18 RAPD primers, the percentage of polymorphism loci was up to 60%. The results indicated that both of effectivenumber of alleles and gene diversity located middle level and genetic variation of this species mainly existed among provenince rather than within provenance. Dendrom divided twelve provenances into four groups: one was from Arkansas(S), Alabama Tombigbee(A),another group included Mississippi Tallahatchie(I) and Mississippi Tombigbee(T), others clustered the fourth group.