Key Laboratory for Quality Regulation of Tropical Horticultural Crops of Hainan Province, School of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China.
State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Genes (Basel). 2024 Aug 20;15(8):1097. doi: 10.3390/genes15081097.
Fruit weight is an important agronomic trait in pepper production and is closely related to yield. At present, many quantitative trait loci (QTL) related to fruit weight have been found in pepper; however, the genes affecting fruit weight remain unknown. We analyzed the fruit weight-related quantitative traits in an intraspecific cross between the cultivated species blocky-type pepper, cv. Qiemen, and the bird pepper accession, "129-1" ( var. ), which was the wild progenitor of . Using the QTL-seq combined with the linkage-based QTL mapping approach, QTL detection was performed; and two major effects of QTL related to fruit weight, and , were identified on chromosomes 2 and 3. The maximum explained 12.28% of the phenotypic variance observed in two F generations, with the maximum LOD value of 11.02, respectively; meanwhile, the maximum explained 15.50% of the observed phenotypic variance in the two F generations, with the maximum LOD value of 11.36, respectively. was narrowed down to the 1.22 Mb region using homozygous recombinant screening from BCS and BCS populations, while was narrowed down to the 4.61Mb region. According to the transcriptome results, a total of 47 and 86 differentially expressed genes (DEGs) in the candidate regions of and were identified. Further, 19 genes were selected for a qRT-PCR analysis based on sequence difference combined with the gene annotation. Finally, and are the most likely candidate genes for , and may be a candidate gene for . Taken together, our results identified and fine-mapped two major QTL for fruit weight in pepper that will facilitate marker-assistant breeding for the manipulation of yield in pepper.
果实重量是辣椒生产中的一个重要农艺性状，与产量密切相关。目前，已在辣椒中发现了许多与果实重量相关的数量性状位点（QTL），但影响果实重量的基因仍不清楚。我们分析了栽培品种块状辣椒（cv. Qiemen）和鸟类辣椒品系“129-1”（var.）之间种内杂交后代的果实重量相关的数量性状，“129-1”是辣椒的野生祖先。利用 QTL-seq 结合基于连锁的 QTL 作图方法进行 QTL 检测，在第 2 号和第 3 号染色体上鉴定到与果实重量相关的两个主要效应 QTL 和 。最大解释了两个 F2 代观察到的表型方差的 12.28%，最大 LOD 值分别为 11.02；同时，最大解释了两个 F2 代观察到的表型方差的 15.50%，最大 LOD 值分别为 11.36。通过对 BCS 和 BCS 群体的纯合重组筛选，将 缩小到 1.22 Mb 区域，而 将 缩小到 4.61 Mb 区域。根据转录组结果，在 和 的候选区域共鉴定到 47 个和 86 个差异表达基因（DEGs）。进一步，根据序列差异结合基因注释，选择了 19 个基因进行 qRT-PCR 分析。最后， 和 可能是 的候选基因， 可能是 的候选基因。总之，我们的研究结果鉴定并精细定位了辣椒果实重量的两个主要 QTL，这将有助于辣椒产量的标记辅助选择育种。
