Haplotype diversity of Heterodera koreana (Tylenchida: Heteroderidae), affecting bamboo in Korea

In a survey of plant-parasitic nematodes in agricultural fields, cyst-forming nematodes were found in soil planted bamboo in Korea. The aim of this study was to identify the cyst nematodes based on morphological and molecular characteristics. As the results, the morphology and morphometrics of cysts and second-stage juveniles (J2s) were consistent with those of previous descriptions of Heterodera koreana. In phylogenetic analyses based on DNA sequences, these cyst nematodes were clustered together with clade of H. koreana in internal transcribed spacer (ITS) region, and large subunit D2-D3 segments (LSU D2-D3). These nematodes were clustered together with clade of H. koreana in cytochrome c oxidase subunit I (COI) gene, but a haplotype was different when compared with previous reported haplotypes (haplotype A-C) in Japan. This study showed these cyst nematodes were identified as H. koreana, and a new haplotype of H. koreana is distributed in Korea. We suggest that the new haplotype of H. koreana name as haplotype D.