The disease late blight is a threat to potato production worldwide, making genetic resistance an important target for breeding. The resistance gene RB/Rpi-blb1 is effective against most strains of the causal pathogen, Phytophthora infestans. Until now, potato breeders have utilized a Sequence Characterized Amplified Region (SCAR) marker to screen for RB. Our objective was to design and validate a Kompetitive Allele Specific PCR (KASP) marker, which has advantages for high-throughput screening. First, the accuracy of the SCAR marker was confirmed in two segregating tetraploid populations. Then, using whole genome sequencing data for two RB-positive segregants and a diverse set of 23 RB-negative varieties, a SNP in the 5’ untranslated (UTR) region was identified as unique to RB. The KASP marker based on this SNP, which had 100% accuracy in the cultivated diversity panel, was used to generate diploid breeding lines containing RB. The KASP marker is publicly available for others to utilize.

晚疫病对全世界的马铃薯生产构成威胁，使得遗传抗性成为育种的重要目标。抗性基因RB / Rpi-blb1对致病病原体致病疫霉的大多数菌株有效。到目前为止，马铃薯育种者一直使用序列特征扩增区域 (SCAR) 标记来筛选RB。我们的目标是设计和验证具有高通量筛选优势的竞争性等位基因特异性 PCR (KASP) 标记。首先，在两个分离的四倍体群体中确认了 SCAR 标记的准确性。然后，使用两个RB阳性分离子和一组不同的 23 个RB的全基因组测序数据阴性品种，5' 非翻译 (UTR) 区域的 SNP 被确定为RB独有的。基于该 SNP 的 KASP 标记在栽培多样性面板中具有 100% 的准确性，用于生成包含RB 的二倍体育种系。KASP 标记公开可供其他人使用。