Construction Of Fingerprinting And Identification Of Authenticity And Purity With SSR Markers For Upland Cotton In Xinjiang

Cotton is one of the most important agricultural products in China.Xinjiang shoulder the important task of China's cotton production safety.With the accelerated development of seed industry and the improvement of marketization,performance of cotton varieties homogenization,seed quality decreased,counterfeit varieties and other issues outstanding,which seriously affect the healthy development of the cotton industry.The establishment of DNA fingerprint and variety identification methods is very important.In addition,strengthening the technical innovation in seed breeding,seed production,seed processing,seed testing and seed management is also essential.It is necessary to provide efficient technical means for seed quality identification.In this study,120 upland cotton varieties were used as materials which were widely grown varieties of Xinjiang in recent 40 years.The DNA fingerprints of Xinjiang upland cotton cultivars were established,and the genetic diversity was analyzed.In addition,the methods of detecting the authenticity and purity of cotton varieties were discussed.The main conclusions are as follow:1.In this paper,78 pairs of core markers were screened from the 586 polymorphic primers,which were distributed in the whole genome of cotton.There were many differences in the number of alleles and the number of polymorphic loci were detected because of the markers on different chromosomes.The 78 core markers were evenly covered with 26 pairs of chromosomes,alleles amplified by each pair of primer ranged from 2 to 10,with a mean of 5.03.2.78 SSR markers were used to analyze the fingerprint of 120 upland cotton varieties,The result indicated that 120 upland cotton varieties could be identified by 12 primer combinations at least.UPGMA cluster analysis of genetic distance showed that all of the varieties were clustered in four groups at the genetic distance of 0.68.Cluster analysis and the source of the material has fine consistency.3.10 inbred cottons were explored using 26 pairs of SSR core primers in comparison with the standard cultivar.The results showed that DNA fingerprint of one variety(Yuanmian 6)shared high uniformity with the standard cultivar,and DNA fingerprints of nine varieties had 8–18 different loci with the standard cultivar.The results from SSR molecular marker matched with the field experiments.4.Five specific primers were selected for testing authenticity of each cultivar from core primers.The results showed that the variety with highest purity was Yuanmian 6,which was 98.0% and that with lowest purity was Yuanmian 1,which was 90.5%.The SSR molecular marker identification result showed that field experiment was positively correlated with morphological traits.In this way,we established a set of simple,fast technical system of the cotton varieties authenticity and purity identification system.