基于GBS简化基因组技术的宽杯杜鹃遗传多样性分析

宽杯杜鹃花色纯黄且钟状花冠簇生于枝顶,具有较高的观赏价值。近年来受道路建设及盗挖盗伐等人为影响,其生境破碎化严重且种群规模日渐萎缩,对其开展保护生物学研究已迫在眉睫。本研究采用基因分型(genotyping-by-sequencing,GBS)技术对宽杯杜鹃老君山(LJS)与大黑山(DHS)两个残存种群进行单核苷酸多态性(single-nucleotide-polymorphism,SNP)位点挖掘与遗传多样性分析。结果表明,通过获得的103 133个高质量SNP位点分析发现两个种群在物种水平上具有较低的遗传多样性(Ne=1.3086,Ho=0.1878,He=0.1856),而种群间具有较高的遗传分化(Fst=0.1765),种群间基因流(Nm)=1.1674。聚类分析、主成分分析与种群遗传结构分析表明36个个体被聚为2个不同的遗传类群。本研究首次揭示了宽杯杜鹃较低的遗传多样性现状,有助于进一步了解其濒危机理和科学地制定宽杯杜鹃保护措施。

Genetic Diversity Assessment of Rhododendron sinofalconeri with Genotyping by Sequencing(GBS)

Rhododendron sinofalconerihas high ornamental value with its pure yellow flower and bell-shaped corollas clustered on the top of the branches. In recent years,due to the anthropogenic impact of road construction,illegal excavation and other human activities,its habitat was severely fragmented and its population was shrunk. Therefore,it was urgent to research on conservation biology of R.sinofalconeri. Singlenucleotide-polymorphism(SNP)site mining and genetic diversity analysis were performed on two surviving populations of Laojunshan(LJS)and Daheishan(DHS)using genotyping-by-sequencing(GBS)technology. As a consequence,analysis of the 103 133 high-quality SNPs revealed that the two populations had lower genetic diversity at the species level(Ne=1.308 6,Ho=0.187 8,and He=0.185 6),and higher genetic differentiation(Fst=0.176 5)at population level. The value of gene flow(Nm)between populations was 1.167 4. By cluster analysis,principal component analysis and population genetic structure analysis,36 individuals were clustered into two different genetic groups. This study revealed the current situation of relatively low genetic diversity of R.sinofalconeri for the first time,which was helpful to further understand the endangered and scientific formulation of conservation measures.