{"title":"Identification of late blight resistance QTLs <i>in an interspecific RIL population of tomato</i> via genotyping-by-sequencing.","authors":"Mengyuan Jia, Hudson Ashrafi, Majid R Foolad","doi":"10.1007/s11032-025-01560-6","DOIUrl":null,"url":null,"abstract":"<p><p>Late blight (LB), caused by <i>Phytophthora infestans</i>, is a destructive disease of the cultivated tomato, <i>Solanum lycopersicum</i>. Environmental concerns and pathogen resistance have propelled research towards developing host resistance. The current LB-resistant cultivars of tomato exhibit susceptibility under severe disease pressure, necessitating the identification, characterization, and incorporation of additional resistance genes into new tomato cultivars. Recently, we identified <i>Solanum pimpinellifolium</i> accession PI 270443 with strong resistance to LB and developed a RIL population from its cross with an LB-susceptible tomato breeding line. In the present study, we constructed a high-density genetic map of the RIL population, using 8,470 SNP markers set into 1,195 genomic bins, with a total genetic distance of 1232 cM and an average bin size of 1 cM. We identified 2 major adjoining LB-resistance QTLs on chromosome 10 and a few minor QTLs on chromosomes 1 and 12 of PI 270443. While one of the QTLs on chromosome 10 colocalized with the known LB-resistance gene <i>Ph- 2</i> and a LB-resistance QTL previously identified in an F<sub>2</sub> population of the same cross, the present study allowed marker saturation of the region, fine mapping of the QTL, and identification of candidate resistance genes in the region. One of the 2 major QTLs on chromosome 10 and the 3 QTLs on chromosomes 1 and 12 were not previously reported in <i>S. pimpinellifolium</i> for LB resistance. These results will expedite transferring of LB resistance from PI 270443 into the tomato cultigen via MAS and discovering the underpinning LB-resistance genes in PI 270443.</p><p><strong>Supplementary information: </strong>The online version contains supplementary material available at 10.1007/s11032-025-01560-6.</p>","PeriodicalId":18769,"journal":{"name":"Molecular Breeding","volume":"45 4","pages":"43"},"PeriodicalIF":2.6000,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11979090/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Molecular Breeding","FirstCategoryId":"97","ListUrlMain":"https://doi.org/10.1007/s11032-025-01560-6","RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2025/4/1 0:00:00","PubModel":"eCollection","JCR":"Q1","JCRName":"AGRONOMY","Score":null,"Total":0}
引用次数: 0
Abstract
Late blight (LB), caused by Phytophthora infestans, is a destructive disease of the cultivated tomato, Solanum lycopersicum. Environmental concerns and pathogen resistance have propelled research towards developing host resistance. The current LB-resistant cultivars of tomato exhibit susceptibility under severe disease pressure, necessitating the identification, characterization, and incorporation of additional resistance genes into new tomato cultivars. Recently, we identified Solanum pimpinellifolium accession PI 270443 with strong resistance to LB and developed a RIL population from its cross with an LB-susceptible tomato breeding line. In the present study, we constructed a high-density genetic map of the RIL population, using 8,470 SNP markers set into 1,195 genomic bins, with a total genetic distance of 1232 cM and an average bin size of 1 cM. We identified 2 major adjoining LB-resistance QTLs on chromosome 10 and a few minor QTLs on chromosomes 1 and 12 of PI 270443. While one of the QTLs on chromosome 10 colocalized with the known LB-resistance gene Ph- 2 and a LB-resistance QTL previously identified in an F2 population of the same cross, the present study allowed marker saturation of the region, fine mapping of the QTL, and identification of candidate resistance genes in the region. One of the 2 major QTLs on chromosome 10 and the 3 QTLs on chromosomes 1 and 12 were not previously reported in S. pimpinellifolium for LB resistance. These results will expedite transferring of LB resistance from PI 270443 into the tomato cultigen via MAS and discovering the underpinning LB-resistance genes in PI 270443.
Supplementary information: The online version contains supplementary material available at 10.1007/s11032-025-01560-6.
期刊介绍:
Molecular Breeding is an international journal publishing papers on applications of plant molecular biology, i.e., research most likely leading to practical applications. The practical applications might relate to the Developing as well as the industrialised World and have demonstrable benefits for the seed industry, farmers, processing industry, the environment and the consumer.
All papers published should contribute to the understanding and progress of modern plant breeding, encompassing the scientific disciplines of molecular biology, biochemistry, genetics, physiology, pathology, plant breeding, and ecology among others.
Molecular Breeding welcomes the following categories of papers: full papers, short communications, papers describing novel methods and review papers. All submission will be subject to peer review ensuring the highest possible scientific quality standards.
Molecular Breeding core areas:
Molecular Breeding will consider manuscripts describing contemporary methods of molecular genetics and genomic analysis, structural and functional genomics in crops, proteomics and metabolic profiling, abiotic stress and field evaluation of transgenic crops containing particular traits. Manuscripts on marker assisted breeding are also of major interest, in particular novel approaches and new results of marker assisted breeding, QTL cloning, integration of conventional and marker assisted breeding, and QTL studies in crop plants.