Inter-Research > DAO > v139 > p121-130  
DAO
Diseases of Aquatic Organisms

via Mailchimp

DAO 139:121-130 (2020)  -  DOI: https://doi.org/10.3354/dao03461

Low internal transcribed spacer rDNA variation in New Zealand Bonamia ostreae: evidence for a recent arrival

Henry S. Lane1,3,*, J. Brian Jones2

1Animal Health Laboratory, Diagnostic and Surveillance Services, Biosecurity New Zealand, PO Box 40742, Upper Hutt 5018, New Zealand
2Murdoch University, Perth, Western Australia 6150, Australia
3Present address: National Institute of Water and Atmospheric Research, Riccarton, Christchurch 8013, New Zealand
*Corresponding author:

ABSTRACT: Bonamia ostreae is a haplosporidian parasite of oysters that was first reported to occur in the Southern Hemisphere in 2015 in the New Zealand flat oyster Ostrea chilensis. Until that report, B. ostreae had been restricted to populations of O. edulis within the Northern Hemisphere. This large range extension raised questions regarding B. ostreae dispersal, including whether B. ostreae is a recent introduction and from where it originated. The whole 18S rRNA gene of New Zealand B. ostreae revealed 99.9-100% sequence homology to other published B. ostreae 18S rDNA sequences. Internal transcribed spacer (ITS) rDNA sequences (n = 29) were generated from New Zealand B. ostreae and compared to published B. ostreae sequences from 3 Northern Hemisphere sites: California, USA (n = 18), Maine, USA (n = 7), and the Netherlands (n = 6) to investigate intraspecific variation. Low ITS rDNA variation was observed from New Zealand B. ostreae isolates, and high levels of variation were observed from Northern Hemisphere B. ostreae sequences. We hypothesise that the low ITS rDNA diversity found in New Zealand B. ostreae is the result of a founder effect resulting from a single introduction from a limited number of propagules. The high level of ITS rDNA variation from the Northern Hemisphere prevented inferences of dispersal origins. New Zealand B. ostreae were genetically differentiated from all sites, and additional genetic data are required to better determine the origin of B. ostreae in New Zealand.


KEY WORDS: Internal transcribed spacer · ITS · Dispersal · Genetic bottleneck · Incursion · Evolution


Full text in pdf format 
Cite this article as: Lane HS, Jones JB (2020) Low internal transcribed spacer rDNA variation in New Zealand Bonamia ostreae: evidence for a recent arrival. Dis Aquat Org 139:121-130. https://doi.org/10.3354/dao03461

Export citation
Mail this link - Contents Mailing Lists - RSS
Facebook - - linkedIn