Department of Agriculture, Forestry and Bioresources, Research Institute of Agriculture and Life Sciences, Plant Genomics and Breeding Institute, College of Agriculture and Life Sciences, Seoul National University, Seoul, Korea.
ECOSEED, Gimje-si, South Korea.
PLoS One. 2022 Feb 17;17(2):e0264026. doi: 10.1371/journal.pone.0264026. eCollection 2022.
Disease caused by Pepper yellow leaf curl virus (PepYLCV) is one of the greatest threats to pepper (Capsicum spp.) cultivation in the tropics and subtropics. Resistance to PepYLCV was previously identified in a few Capsicum accessions, but no resistance QTLs have been mapped. This study aimed to elucidate the genetics of PepYLCV resistance in C. annuum L. Augmented inoculation by the viruliferous whitefly Bemisia tabaci was used to evaluate parental lines and an F2 segregating population derived from a cross between resistant C. annuum line LP97 and susceptible C. annuum line ECW30R. Final evaluation was performed six weeks after inoculation using a standardized 5-point scale (0 = no symptoms to 4 = very severe symptoms). A high-density linkage map was constructed using genotyping-by-sequencing (GBS) to identify single-nucleotide polymorphism (SNP) markers associated with PepYLCV resistance in the F2 population. QTL analysis revealed three QTLs, peplcv-1, peplcv-7, and peplcv-12, on chromosomes P1, P7, and P12, respectively. Candidate genes associated with PepYLCV resistance in the QTL regions were inferred. In addition, single markers Chr7-LCV-7 and Chr12-LCV-12 derived from the QTLs were developed and validated in another F2 population and in commercial varieties. This work thus provides not only information for mapping PepYLCV resistance loci in pepper but also forms the basis for future molecular analysis of genes involved in PepYLCV resistance.
由胡椒曲叶病毒（PepYLCV）引起的疾病是热带和亚热带地区胡椒（Capsicum spp.）种植的最大威胁之一。先前在一些辣椒品种中发现了对 PepYLCV 的抗性，但尚未定位到抗性 QTL。本研究旨在阐明辣椒对 PepYLCV 抗性的遗传基础。采用带毒烟粉虱增强接种的方法，评估了亲本系和来自抗性辣椒系 LP97 和敏感辣椒系 ECW30R 杂交的 F2 分离群体。接种后六周，采用标准化的 5 分制（0 = 无症状，4 = 非常严重症状）进行最终评估。利用基于测序的基因型鉴定（GBS）构建高密度连锁图谱，以鉴定与 F2 群体中 PepYLCV 抗性相关的单核苷酸多态性（SNP）标记。QTL 分析在 P1、P7 和 P12 染色体上分别鉴定出三个 QTL，分别命名为 peplcv-1、peplcv-7 和 peplcv-12。在 QTL 区域推断出与 PepYLCV 抗性相关的候选基因。此外，从 QTL 中衍生的单标记 Chr7-LCV-7 和 Chr12-LCV-12 在另一个 F2 群体和商业品种中得到了开发和验证。这项工作不仅为辣椒中 PepYLCV 抗性基因座的作图提供了信息，而且为 PepYLCV 抗性相关基因的进一步分子分析奠定了基础。
