Bettinelli Paola, Nicolini Daniela, Costantini Laura, Stefanini Marco, Hausmann Ludger, Vezzulli Silvia
Center Agriculture Food Environment (C3A), University of Trento, 38098 San Michele all'Adige, TN, Italy.
Grapevine Genetics and Breeding Unit, Research and Innovation Centre, Fondazione Edmund Mach, 38098 San Michele all'Adige, TN, Italy.
Int J Mol Sci. 2023 Feb 10;24(4):3568. doi: 10.3390/ijms24043568.
Black rot (BR), caused by , is an emergent fungal disease threatening viticulture and affecting several mildew-tolerant varieties. However, its genetic bases are not fully dissected yet. For this purpose, a segregating population derived from the cross 'Merzling' (hybrid, resistant) × 'Teroldego' (, susceptible) was evaluated for BR resistance at the shoot and bunch level. The progeny was genotyped with the GrapeReSeq Illumina 20K SNPchip, and 7175 SNPs were combined with 194 SSRs to generate a high-density linkage map of 1677 cM. The QTL analysis based on shoot trials confirmed the previously identified ()1 locus on chromosome 14, which explained up to 29.2% of the phenotypic variance, reducing the genomic interval from 2.4 to 0.7 Mb. Upstream of 1, this study revealed a new QTL explaining up to 79.9% of the variance for bunch resistance, designated 3. The physical region encompassing the two QTLs does not underlie annotated resistance ()-genes. The 1 locus resulted enriched in genes belonging to phloem dynamics and mitochondrial proton transfer, while 3 presented a cluster of pathogenesis-related Germin-like protein genes, promoters of the programmed cell death. These outcomes suggest a strong involvement of mitochondrial oxidative burst and phloem occlusion in BR resistance mechanisms and provide new molecular tools for grapevine marker-assisted breeding.
黑腐病（BR）由[病原体名称未给出]引起，是一种新兴的真菌病害，威胁着葡萄栽培业，且会影响多个耐白粉病品种。然而，其遗传基础尚未完全解析。为此，对由‘Merzling’（杂交种，抗病）בTeroldego’（[品种特性未给出]，感病）杂交产生的分离群体在新梢和果穗水平上进行了黑腐病抗性评估。利用葡萄重测序Illumina 20K SNP芯片对该后代进行基因分型，并将7175个单核苷酸多态性（SNP）与194个简单序列重复（SSR）相结合，构建了一张1677厘摩（cM）的高密度连锁图谱。基于新梢试验的数量性状位点（QTL）分析证实了先前在14号染色体上鉴定出的（[基因名称未给出]）1位点，该位点解释了高达29.2%的表型变异，将基因组区间从2.4兆碱基（Mb）缩小到0.7 Mb。在1上游，本研究揭示了一个新的QTL，其解释了高达79.9%的果穗抗性变异，命名为3。包含这两个QTL的物理区域并不包含已注释的抗性（[抗性相关基因类型未给出]）基因。1位点富含与韧皮部动态和线粒体质子转移相关的基因，而3位点有一组与病程相关的类萌发素蛋白基因簇，这些基因是程序性细胞死亡的启动子。这些结果表明线粒体氧化爆发和韧皮部堵塞在黑腐病抗性机制中发挥着重要作用，并为葡萄的分子标记辅助育种提供了新的工具。
