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2025 Vol.38, Issue 6 Preview Page

Research Article

Genetic Diversity and Phylogenetic Relationships in Wild and Cultivated Lactuca Species
Suyun Moon1
,
Yoon-Jung Lee2
,
Seong-Hoon Kim2
,
Dae-Won Ki1
,
Bum-Soo Hahn3
,
Aejin Hwang2
,
Hyeonseok Oh2
,
Tae-Sung Kim4
,
Young-Wang Na3
1Post-doc, National Agrobiodiversity Center, National Institute of Agricultural Sciences, Rural Development Administration, Jeonju 54874, Korea
2Researcher, National Agrobiodiversity Center, National Institute of Agricultural Sciences, Rural Development Administration, Jeonju 54874, Korea
3Senior Researcher, National Agrobiodiversity Center, National Institute of Agricultural Sciences, Rural Development Administration, Jeonju 54874, Korea
4Professor, Department of Agriculture and Life Science, Korea National Open University, Seoul 03087, Korea
*Corresponding Author
1 December 2025. pp. 737-747
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Abstract

Lettuce (Lactuca sativa) is an economically important leafy vegetable in the family Asteraceae, yet its domestication history and evolutionary relationships with wild relatives remain incompletely understood. We used genotyping- by-sequencing to analyze genome-wide variation across 145 accessions representing five Lactuca species (L. indica, L. saligna, L. sativa, L. serriola, and L. virosa). A total of 5,301 high-quality SNPs were identified and used to assess genetic diversity, population structure, and phylogenetic relationships. Among the species, L. virosa exhibited the highest genetic diversity. Analysis of molecular variance showed that 54% of the total genetic variation was distributed among species, indicating substantial interspecific differentiation. Population structure and phylogenetic analyses supported four major clusters with strong concordance across methods. Among the wild taxa, L. serriola and L. virosa were the most genetically similar to cultivated lettuce. Although interspecific divergence was evident, L. sativa showed moderate genetic connectivity with both species. Directional gene flow analysis inferred migration signals from L. saligna to L. virosa and from L. indica to L. serriola, reflecting complex interspecific interactions. These results provide genomic insights into the diversity and relationships among Lactuca species and offer a foundation for future breeding and germplasm conservation.

Keywords
Gene flow
Genotyping-by-sequencing
Lettuce
Population structure
Wild relatives
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  • Publisher :The Plant Resources Society of Korea
  • Publisher(Ko) :한국자원식물학회
  • Journal Title :Korean Journal of Plant Resources
  • Journal Title(Ko) :한국자원식물학회지
  • Volume : 38
  • No :6
  • Pages :737-747
  • Received Date : 2025-08-04
  • Revised Date : 2025-11-14
  • Accepted Date : 2025-11-14
  • DOI :https://doi.org/10.7732/kjpr.2025.38.6.737
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