Molecular Markers Analysis Of Germplasm Resources Pyrus In Xinjiang And Cloning The Self-incompatibility Genes

Pear is the Rosaceae Pomoideae and Pyrus (Pyrus L.) plants. After decades of conservation, collection and development, Xinjiang pears'resource included the Pyrus sinkiangensis Yu, Bretschnider pear (Pyrus bretschnider), Pyrus pyrifolia systems and so on. Meantime, pear is a kind of typical gametophytic self-incompatibility plant. In this study, we used the molecular marker techniques to analysis the relationship among the 48 pears in Xinjiang. Pears' pollen self-incompatibility genetic S-genotype F-box protein gene SFB (S haplotype-specific F-box protein, SFB) and SFBB (S haplotype-specific F-box brothers, SFBB) were cloned by the biological technology. Molecular markers and bioinformation anlysis are good for use germplasm Resources pear and improved varieties in theory. What's more its good for self-compatible cultivar selection, as well as fruit trees gametophytic self-incompatibility and the molecular mechanism of laying the theoretical basis. All results were summarized as follows:1. The different PCR programs and the ingredients of ISSR and RAPD reaction system such as Taq DNA Polymerase, dNTP, DNA and primers were screened by different concentrations. Suitable reaction systems and programs of the ISSR and RAPD analysis for pear genomic DNA was designed.2. Genetic relationships and diversities of 48 pear accessions were assessed by ISSR and RAPD markers. Using cluster analysis (UPGMA) based on those polymorphism bands amplified with ISSR and RAPD primers, the 48 accessions were classified into three groups, group I with 1 accessions, group II with 23 accessions, and groupⅢwith 24 accessions.3. In this study, one SFB genes (GenBank accession numbers:GQ456944) were identificated using PCR technolgy in KUERLEXIANGLI mainly planted in China for the first time. The identified SFB genes showed S-haplotypespecific polymorphism. These alleles encoded proteins with the F-box motif in the N-amino terminus, and with four (hyper) variable regions, V1, V2, Hva and Hvb, considered to be recognition site between SFB and S-RNase and determined GSI. With the bioinformatics analysis, the SFB proteins were instable, hydrophilicity and non-secretory protein and had ligase or lyase enzyme activity.F-box gene phylogenetic tree building results showed that KUERLEXIANGLI SFB genes shows difference with Snapdragon.4. KUERLEXIANGLI SFBB and the other seven pears'SFBB genes (GenBank accession numbers: GQ456943, GQ456947, GU901410, GU901408, GU901409, GU901407, GQ456945 and GU901406) were identificated using PCR technolgy. We predicted these genes take part in Lyase and Central_intermediary_metabolism.