【摘要】 奇楠种质与普通白木香种质在结香特点、品质与市场价值上存在显著差异。为实现二者的快速、准确鉴别，本研究拟基于全基因组重测序技术筛选特异性SNP标记，建立一套沉香种质鉴定方法。选取市场主要流通的13份奇楠种质样品和50份普通白木香种质样品进行全基因组重测序，通过计算群体内纯合度（H_p）与群体间分化指数（Fst），初步筛选出在两类群体中均完全固定（H_p=0）且完全分化（Fst=1）的SNP位点，经功能注释后进一步筛选出导致非同义突变的功能基因位点作为候选标记，最终确定位于DLAT基因第1879位点与KASII基因第20位点的2个SNP，其在奇楠种质与普通白木香种质中表现出相反的基因型：所有奇楠种质在2个位点均为纯合TT型，而所有普通白木香种质分为CC型（DLAT）与AA型（KASII）。为验证标记的准确性和普适性，本研究进一步采集5份奇楠新种质与2份普通白木香新种质，通过PCR扩增与Sanger测序进行基因分型，结果与预期完全一致，证实所选SNP标记具备良好的准确性与可靠性。本研究构建了一套基于DLAT和KASII基因SNP标记的沉香种质鉴定方法，实现了分子层面对奇楠种质与普通白木香种质的快速准确识别，为沉香产业的良种选育与市场监管提供技术支撑。更多还原

【Abstract】 Significant differences exist between the precious Qinan germplasm and the common Aquilaria sinensis germplasm in agarwood-forming characteristics, final quality, and market value. To achieve rapid and accurate discrimination between the two germplasm types, this study aimed to develop a molecular identification system for agarwood germplasm based on specific single nucleotide polymorphism(SNP) markers screened through whole-genome resequencing. A total of 13 Qinan germplasm samples and 50 common A. sinensis germplasm samples, representing major commercial varieties, were subjected to whole-genome resequencing. Population genetics analysis, involving the calculation of the pooled heterozygosity(H_p) within each group and the fixation index(Fst) between groups, was employed for the initial screening. SNP loci demonstrating complete fixation within each group(H_p=0) and complete differentiation between the two groups(Fst=1) were selected. Subsequent functional annotation prioritized nonsynonymous mutations within known functional genes as candidate markers. This process led to the identification of two definitive SNP markers, one located at position 1879 of the DLAT gene and the other at position 20 of the KASII gene. The SNPs exhibited opposite genotype patterns between the two germplasms, all Qinan germplasm accessions displayed a homozygous TT genotype at both loci, whereas all common A. sinensis germplasm samples showed a homozygous CC genotype at the DLAT locus and a homozygous AA genotype at the KASII locus. To validate the accuracy and general applicability of the markers, an additional independent set of five novel Qinan germplasms and two novel common A. sinensis germplasms were collected and analyzed using PCR amplification followed by Sanger sequencing for genotyping. The genotyping results were completely consistent with the expected patterns, confirming the high accuracy and reliability of the selected SNP markers. In conclusion, this study successfully established a robust SNP-based identification method utilizing markers within the DLAT and KASII genes. This method enables rapid, accurate, and molecular-level discrimination between the precious Qinan germplasm and the common A. sinensis germplasm. The established protocol would provide practical technical support for the breeding of superior agarwood varieties and the effective regulation of the agarwood market.更多还原