Abstract
The oomycete genus Olpidiopsis encompasses pathogens of red seaweeds, including the most economically damaging disease in Pyropia (ex-Porphyra) farms in Asia. Here we identified three new Olpidiopsis species: Olpidiopsis palmariae, O. muelleri, and O. polysiphoniae spp. nov. as well as a Scottish variety of O. porphyrae, a devastating pathogen only reported in Japanese seaweed farms, which is also described as O. porphyrae var. scotiae. Importantly, two of the new species infected Porphyra and Palmaria sp., which are the subjects of extensive farming trials in Europe and North America. To further assess the extent of undescribed Olpidiopsis diversity and the threat it might pose to aquaculture in different regions, we screened targeted metagenomes of Porphyra umbilicalis blades collected on the West and East Northern Atlantic shores (JGI proposal ID 946). Four different Olpidiopsis OTUs were detected on at least 5 out of 9 Porphyra blade metagenomes, illustrating the prevalence and diversity of these parasites in wild Porphyra populations. Finally, we extended our screening efforts to global metabarcoding campaigns, revealing over 700 new
– 55 –
sequences attributable to Olpidiopsis with a worldwide distribution. Close relatives of the Korean O. pyropiae are reported for the first time in Europe and the United States. In the light of our restricted sampling, our results highlight the diversity and abundance of Olpidiopsis worldwide. In the context of worsening impact of Olpidiopsis pathogens in Asia, this worldwide distribution should be treated as a serious threat to the global seaweed industry and wild red algal populations. Our data call for more efforts towards the documentation of these pathogens, and for adequate biosecurity measures to be developed.
– 55 –
sequences attributable to Olpidiopsis with a worldwide distribution. Close relatives of the Korean O. pyropiae are reported for the first time in Europe and the United States. In the light of our restricted sampling, our results highlight the diversity and abundance of Olpidiopsis worldwide. In the context of worsening impact of Olpidiopsis pathogens in Asia, this worldwide distribution should be treated as a serious threat to the global seaweed industry and wild red algal populations. Our data call for more efforts towards the documentation of these pathogens, and for adequate biosecurity measures to be developed.
Original language | English |
---|---|
Article number | 111 |
Pages (from-to) | 54-55 |
Journal | Phycologia |
Volume | 56 |
Issue number | 4(Supplement) |
DOIs | |
Publication status | Published - Aug 2017 |