Rapid identification of 13 Hubei tea cultivars by MCID method based on SSR fluorescent markers

ObjectiveIn order to provide theoretical basis for the evaluation of Hubei tea germplasm resources,pro-tection of varieties and early identification of the purity of seedlings,manual cultivar identification diagram(MCID)was constructed to quickly distinguish and identify Hubei tea cultivars.MethodThirty pairs of fluorescent SSR markers dis-tributed evenly on the genetic linkage group were used to carried out PCR amplification of thirteen Hubei fine tea culti-vars. Fluorescence labeled capillary electrophoresis was used to detect the amplification products and screen the core pri-mers. The cultivar identification diagram(CID)was drawn by MCID method.ResultThirty pairs of SSR primers ampli-fied 145 alleles,ranging from 3 to 9 alleles for each primer,with an average of 4.83. A total of 194 genotypes were detec-ted,and the genotypes detected by each primer were 3 to 12 with an average of 6.47. The range of polymorphism informa-tion content(PIC)was 0.29-0.85 with an average of 0.58. Relationship analysis showed that Nei's genetic distance of the 13 tea cultivars was 0.19-0.44,and were classified into three groups by Neighbor-Joining(NJ)method based on Nei's ge-netic distance(Nei's genetic distance was 0.16). It indicated that cultivars with the same geographical origin may grouped due to similar genetic backgrounds,or may also show great differences because of their different parental origin. Three pairs of SSR primers,TM547,TM552 and TM107,could rapidly identify all the tested cultivars. According to the CID map constructed by MCID method,the primers needed for the identification of various tea cultivars and their correspon-ding genotypes could be seen directly.ConclusionThe MCID method based on fluorescent SSR markers is rapid,accu-rate and efficient in identification of tea cultivars. It can support the intellectual property protection,seedling appraisal and variety identification of Hubei fine tea cultivars.