Taxonomy and Phylogeny of Species (Oomycota) Parasitic to and in Korea, with the Introduction of sp. nov.

The genus , an obligate biotrophic group belonging to Oomycota, causes serious damage to a variety of wild and ornamental plants, as well as cultivated crops, such as beet, rose, spinach, and tobacco. To investigate the diversity of species parasitic to and (Caryophyllaceae) plants in Korea, we performed a morphological analysis on dried herbarium specimens and molecular phylogenetic inferences based on internal transcribed spacer rDNA and mitochondrial DNA sequences. As a result, it was confirmed that there are four species of parasitic to specific species of and , all of which were hitherto unrecorded in Korea: (ex ), (ex ), (ex ), and (ex ). In addition, specimens parasitic to davidii differed morphologically from owing to the large and ellipsoidal conidia; this morphological discrepancy was also validated by the high genetic divergence between the two species. sp. nov. is described and illustrated here.