Abstract

To estimate genetic diversity and genetic structures of Q. liaotungensis at different altitudes in Xingtangsi, eight natural populations were surveyed by sequence-related amplified polymorphism (SRAP) markers. A total of 179 bands were amplified by 12 pairs of SRAP primer combinations. The average number of amplification band for each pair primers was 14.9. The percentage polymorphic band (PPB) of Q. liaotungensis was 100%, Nei’s gene diversity (H) and Shannon information index (I) was 0.3482 and 0.5264 respectively, which indicated the high genetic diversity occurred in Q. liaotungensis populations. The highest genetic diversity harbored in population 6, while the lowest in population 4. The genetic diversity of all eight studied populations showed a low-high-low variation pattern along elevation gradients. Analysis of molecular variance (AMOVA) explored that the genetic variation mainly existed within populations (80%) and only 20% of genetic variation between populations of Q. liaotungensis (p<0.001). STRUCTURE and Principal coordinate analysis (PCoA) further confirmed the AMOVA analysis. Based on the genetic distance between populations, eight populations were mainly clustered into two groups. Q. liaotungensis' intrinsic biological characteristics, effective gene flow and microenvironmental heteroplasmy resulted in the genetic distribution of Q. liaotungensis populations in Xingtangsi.

Key words: Genetic diversity, gene flow, Q. liaotungensis, sequence-related amplified polymorphism (SRAP), Xingtangsi.