A comparison of the organelle genomes of two domestic

Orobanche species

Sang-Chul Kimp, Eun Su Kang, Tae-Hee Kim, Ye-Rim Choi, Joonhyung Jung, Hyuk-Jin Kimc

(Forest Biodiversity Division, Korea National Arboretum)

Abstract: Orobanchaceae Vent. includes approximately 2,060 species across 90 genera, found on all continents except Antarctica. The genus Orobanche consists of non-chlorophyllous plants that parasitize various host roots. In Korea, two endangered Orobanche species are present, both parasitizing Artemisia spp. O. filicicola was collected from Jeju Island (ESK24-005), while O. coerulescens was analyzed by collecting two populations: one from Jeju Island and another from Pohang (ESK24-017), including individuals that were previously classified as Orobanche coerulescens f. alba (ESK24-003). The chloroplast genome lengths were 90,050–90,137 bp for O. coerulescens and 91,518–91,529 bp for O. filicicola, with the latter containing the unique psbM gene. Mitochondrial analysis revealed 57 genes, with lengths between 1,058,991 and 1,144,414 bp. Comparative analysis indicated a 99.6% similarity among four O. coerulescens individuals, with significant genetic differences between Jeju Island and Incheon individuals. Phylogenetic analysis revealed differences between the chloroplast and mitochondrial phylogenies. In the case of chloroplasts, O. coerulescens and O. filicicola were clearly distinguished. However, for mitochondria, O. coerulescens formed two clades and established a lineage with O. filicicola. These results are that O. filicicola has diverged from O. coerulescens, suggesting speciation. Further studies are needed to explore genetic diversity and speciation processes within O. coerulescens populations.

Keywords: Organelle genome, Orobanche filicicola, Orobanche coerulescens, Orobanchaceae, Phylogenomic

Funding: This research was funded by grants from Scientific Research (KNA1-1-13-14-1) of the Korea National Arboretum.