Oh Heeduk, Mengist Molla F, Ma Guoying, Giongo Lara, Pottorff Marti, Spencer Jessica A, Perkins-Veazie Penelope, Iorizzo Massimo
Plants for Human Health Institute, North Carolina State University, Kannapolis, NC, 28081, USA.
Department of Horticulture, North Carolina State University, Raleigh, NC, 27607, USA.
BMC Plant Biol. 2025 Jan 10;25(1):36. doi: 10.1186/s12870-025-06061-4.
Fruit quality traits, including taste, flavor, texture, and shelf-life, have emerged as important breeding priorities in blueberry (Vaccinium corymbosum). Organic acids and sugars play crucial roles in the perception of blueberry taste/flavor, where low and high consumer liking are correlated with high organic acids and high sugars, respectively. Blueberry texture and appearance are also critical for shelf-life quality and consumers' willingness-to-pay. As the genetic mechanisms that determine these fruit quality traits remain largely unknown, in this study, an F mapping population was used to perform quantitative trait loci (QTL) mapping for pH, titratable acidity (TA), organic acids, total soluble solids (TSS), sugars, fruit size, and texture at harvest and/or post-storage and weight loss.
Twenty-eight QTLs were detected for acidity-related parameters (pH, TA, and organic acid content). Six QTLs for pH, TA, and citric acid, two for quinic acid, and two for shikimic acid with major effects were consistently detected across two years on the same genomic regions on chromosomes 3, 4, and 5, respectively. Putative candidate genes for these QTLs were also identified using comparative transcriptomic analysis. No QTL was detected for malic acid content, TSS, or individual sugar content. A total of 146 QTLs with minor effects were identified for texture- and size-related parameters. With a few exceptions, these QTLs were generally inconsistent over years and post-storage, indicating a highly quantitative nature.
Our findings enhance the understanding of the genetic basis underlying fruit quality traits in blueberry and guide future work to exploit DNA-informed selection strategies in blueberry breeding programs. The major-effect QTLs identified for acidity-related fruit characteristics could be potential targets to develop DNA markers for marker-assisted selection (MAS). On the other hand, genomic selection may be a more suitable approach than MAS when targeting fruit texture, sugars, or size.
果实品质性状，包括口感、风味、质地和货架期，已成为蓝莓（越橘）重要的育种优先目标。有机酸和糖类在蓝莓口感/风味感知中起着关键作用，消费者对其喜爱程度低和高分别与高有机酸含量和高糖含量相关。蓝莓的质地和外观对货架期品质和消费者的支付意愿也至关重要。由于决定这些果实品质性状的遗传机制在很大程度上仍不明确，本研究利用一个F作图群体对采收时和/或贮藏后及失重情况下的pH值、可滴定酸度（TA）、有机酸、总可溶性固形物（TSS）、糖类、果实大小和质地进行数量性状位点（QTL）定位。
检测到28个与酸度相关参数（pH值、TA和有机酸含量）的QTL。在第3、4和5号染色体的相同基因组区域，连续两年一致检测到6个影响pH值、TA和柠檬酸的QTL，2个影响奎尼酸的QTL，以及2个影响莽草酸的具有主要效应的QTL。还通过比较转录组分析鉴定了这些QTL的推定候选基因。未检测到苹果酸含量、TSS或单个糖类含量的QTL。共鉴定出146个对质地和大小相关参数有微小影响的QTL。除少数例外，这些QTL在不同年份和贮藏后通常不一致，表明其具有高度的数量性状性质。
我们的研究结果增进了对蓝莓果实品质性状遗传基础的理解，并为未来在蓝莓育种计划中利用基于DNA的选择策略的工作提供了指导。为与酸度相关的果实特征鉴定出的主要效应QTL可能是开发用于标记辅助选择（MAS）的DNA标记的潜在目标。另一方面，在针对果实质地、糖类或大小进行选择时，基因组选择可能比MAS更合适。
