Abstract:To study the genetic diversity of Triplophysa yarkandensis in the Tarim River basin, high-throughput sequencing was used to sequence the genome of T. yarkandensis. We screened for qualified microsatellite loci and designed 100 primers pairs for PCR. A high-throughput sequencing platform was used to randomly sequence the genome of Riplophysa yarkandensis and eligible microsatellite loci were selected to design primers for PCR. Finally, 39 primers pairs with polymorphisms were selected. Fifteen pairs were randomly selected to be amplified in the five river populations of T. yarkandensis. The results showed that the average and effective alleles of the five T. yarkandensis populations were 48.467 and 15.181, respectively. The observed heterozygosity (Ho) and expected heterozygosity (He) were 0.578 and 0.929, respectively. The polymorphism information content (PIC) was 0.893. The index of gene differentiation (Fst) was 0.102. The highest number of alleles was in Che'erchen Lake (18.143), and the lowest number of alleles was in the Akesu River (10.429). The observed heterozygosity of the Akesu River group was the highest (0.706), while the observed heterozygosity of the Taitema Lake group was the lowest (0.517). The polymorphic information content of the Algan population was the highest (0.877), and the polymorphic information content of the Akesu River population was the lowest (0.760). The genetic distance between the Akesu River and Tainan River populations was the smallest (0.606), while the genetic distance between the Algan River and Tainan River populations was the largest (1.901). The genetic similarity between the Algan and Tainan River populations was low (0.149), and the genetic similarity between the Akesu and Tainan River populations was high (0.545). Genetic structuring showed that Che'erchen and Taitema Lakes, Akesu and Tainan Rivers, and the Algan group clustered in one branch. The results of this study show that there are differences among T. yarkandensis populations in the Tarim River, but gene exchange is ongoing.
