Construction Of Fingerprints And Analysis Of Geneti Relationships Among Hybrids Of Populus Deltoides×Section Tacamahaca Using SSR And SCoT Markers

Populus deltoides×Section tacamahaca is an excellent hybrid combinations,which can select fast-growing and anti-stress varieties of polar.However,it’s difficult to identify those hybrid clone seedlings accurately by eyes,because there are small differences in their morphological characteristics,especially after defoliation in winter,which impede the varieties breeding process and promotion seriously.Molecular markers is a kind of powerful tool for the identification of breeds and clones and the analysis of genetic relationships.Therefore,using molecular markers for differentiation of hybrid clones,establishment of fingerprints and analysis genetic relationship of populus clones is indispensable.In this study,9 hybrid clones of P.deltoides×S.tacamahaca and 3 their parents were as materials and both SSR and SCoT markers were used to build their fingerprints and analyze their genetic relationship and then compared 2 markers’ applicability in genetic difference.The results were as follows:1.12 polymorphic primers were selected from 20 SSR primers,and these primers amplified 94 clearer bands,in which the polymorphic bands were 85,accounting for 90.4%of the total,and each primer amplified 7.83 bands.All the amplified bands size ranged from100 bp to 300 bp.2.14 polymorphic primers were selected from 36 SCoT primers,and these primers amplified 127 clearer bands,in which the polymorphic bands were 95,accounting for 74.8%of the total,and each primer amplified 9.07 bands.All the amplified bands size ranged from200 bp to 1 500 bp.3.The genetic similarity coefficients of 12 clone materials ranged from 0.4353 to 0.8000 with a mean of 0.6177 and its amplitude of variation was 0.3647,and where the average of similarity coefficients,12 clones were divided into three groups based on SSR marker;the similarity coefficients of 12 clones ranged from 0.4043 to 0.8723 with a mean of 0.6383 and its amplitude of variation was 0.4680,and where the average of similarity coefficients,12 clones were divided into five groups based on SCoT maker.4.85 polymorphic bands based on SSR and 95 polymorphic bands based on SCoT were used for establishing fingerprint of 12 clones respectively,in which every clone’ bands had different size and location,showing a certain genetic differences in DNA level,by which could distinguish them.5.SSR and SCoT markers’ average band informativeness were 0.45,0.40 and effective multiplex ratio were 7.08,6.79 and marker index were 3.19,2.72 respectively with comparing the two kinds of markers.The former value of all indexes more than the latter.6.The result of mantel test showed that the relation of genetic similarity coefficients matrix was significant(r=0.5013,P=0.003)between SSR and SCoT markers for 12 clones,and they are both suit for researching about identification and genetic relationship in hybrids of P.deltoides×S.tacamahaca.