Cluster Analysis on Xinjiang Sea-Island Cotton by SRAP and RGA

【Objective and Method】 The sea-island cotton(Gossypium barbadense) is important due to its fine fiber quality.However,genetic diversity analysis of this species is still poorly documented,which is important for in situ and ex situ germplasm conservation and useful for breeding programs.Genetic diversity of sea-island cotton cultivars from Xinjiang were assessed by SRAP and RGA markers.Jaccard coefficient matrix of two molecular marker data were calculated respectively by NTSYSpc2.1 software and clustering analysis was made by using UPGMA method on all selected materials.【Result】Using 238 SRAP markers,134 polymorphism loci were detected.The number of polymorphic loci per primer ranged from 2 to 8,with an average of 2.91 which showed that more polymorphism loci can be detected and the genetic diversity of sea-island cotton can be reflected better by using SRAP.Using 107 RGA markers,46 polymorphism loci were detected.The number of polymorphic loci per primer ranged from 2 to 5,with an average of 2.08 which showed that more polymorphism loci also can be detected and the resistance genetic diversity of sea-island cotton can be reflected better by using RGA as a molecular marker.【Conclusion】The results showed that the SRAP clustering was basically consistent with pedigree source and the RGA clustering was basically consistent with resistance level of the materials.The molecular marker was proved to play an important role on host identification and genetic diversity study of varieties.