Screening of SSR Core Primers and Construction of Molecular ID for Flue-cured Tobacco Germplasm Resources in Hunan

[Objectives]This study was conducted to establish a reliable and unique molecular ID for flue-cured tobacco germplasm resources in Hunan Province,further improving the efficiency of germplasm collection and identification,and laying a solid material foundation for flue-cured tobacco breeding.[Methods]Twelve pairs of SSR primers with stable amplification and rich polymorphism were screened out from 816 pairs of SSR primers by a step-by-step screening method.As core primers of the SSR core primer library,the polymorphism of SSR primers was analyzed,the genetic relationship of 162 flue-cured tobacco germplasm resources was identified,and the molecular ID cards were constructed.[Results]The result of SSR primer polymorphism analysis showed that a total of 57 alleles were detected by 12 pairs of SSR primers in 165 tobacco germplasm resources,with an average of 4.75 alleles per pair of primers;the average diversity of SSR primers was 0.649;and the average value of Shannon's index was 1.235.The results of cluster analysis showed that 162 flue-cured tobacco germplasm resources were divided into five groups.The members of each group were divided based on genome information,which had nothing to do with their geographical origin.Meanwhile,12 pairs of SSR primers gave each flue-cured tobacco germplasm resource a unique molecular ID code.[Conclusions]From the above results,we can see that the 12 pairs of SSR primers obtained by screening have stable amplification polymorphism,and can serve as the primers of the core primer library,and can be used to construct the unique molecular ID of flue-cured tobacco germplasm resources.