ISSR And SCoT Analysis On The Genetic Diversity Of Camellia Oleifera Germplasms

Camellia oleifera is a cross-pollinated plant.Due to continuous hybridization,there are many varieties of Camellia oleifera and the difference of characters between varieties becomes smaller.In addition,the breeding process of Camellia oleifera is long.Therefore,the excellent varieties need to be found through long-term and a significant amount of research and observation.In this study,inter-simple sequence repeats?ISSR?and start codon targeted?SCoT?polymorphism were used to identify the genetic relationship among 400Camellia oleifera germplasm resources in China,in an effort to provide a theoretical basis for the identification of Camellia oleifera germplasm resources.The main research results and conclusion are as follows:?1?Optimized the ISSR-PCR reaction system with a total reaction volume of 20?L:10?L 2×Taq PCR Master Mix,50 ng template,1.1?L 10?mol/L primer,and the remaining ddH₂O was used.The SCoT-PCR reaction system with a total reaction volume of 20?L was optimized:10?L 2×Taq PCR Master Mix,20 ng template,1.0?L 10?mol/L primer,and the remaining ddH₂O was used.?2?Screening of 12 ISSR primers,and selected 4 primers with better bands.A total of51 band loci and 46 polymorphic loci were amplified by ISSR primers.On average,each primer amplified 12.75 loci and 11.5 polymorphic loci.The average polymorphism percentage was 90.19%.Cluster analysis showed that the similarity coefficient between 400oil tea germplasms was 0.51¹.00.When the similarity coefficient is 0.61,400 test samples can be divided into seven categories.?3?Screening to obtain 3 SCoT primers.SCoT primers amplified 49 band loci and 46polymorphic loci.On average,each primer amplified 16.33 loci and 14.33 polymorphic loci.The average polymorphism percentage was 87.75%.Cluster analysis showed that the similarity coefficient between 400 oil tea germplasms was 0.54¹.00.When the similarity coefficient is 0.66,400 test samples can be divided into eight categories.The PCR optimization system of SCoT in Camellia oleifera was established for the first time and compared with ISSR,which proved its advantages in the study of Camellia oleifera germplasm resources.The established fingerprints of ISSR and SCoT have a certain value for the identification of Camellia oleifera germplasm,both of which reveal the diversity differences between Camellia oleifera germplasm resources at the molecular level,thereby providing a theoretical basis for the breeding and improvement of Camellia oleifera.