Presence of postlarval alvinocaridid shrimps over south-west Indian Ocean hydrothermal vents, with comparisons of the pelagic biomass at different vent sites

Two types of alvinocaridid shrimp postlarvae were taken at plume depth over the Kairei and Edmond hydrothermal vent fields in the south-west Indian Ocean. These postlarvae were superficially indistinguishable from similar postlarvae taken previously over hydrothermal vents in the Atlantic. The micronekton invertebrate taxa in the water column over the Kairei and Edmond sites were similar to those in the Atlantic. The most frequently taken deep-water fish at Kairei was an unidentified cyemid snipe eel, whereas in the Atlantic its place was taken by Gonostoma bathyphilum and species of the melamphaeid Scopeloberyx. Previous sampling over East Pacific Rise hydrothermal sites at 13°N failed to take any alvinocaridid postlarvae, but the ostracod Gigantocypris agassizi was a major component of the micronekton.

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ReNovRisk: a multidisciplinary programme to study the cyclonic risks in the South-West Indian Ocean

Natural Hazards ◽

10.1007/s11069-021-04624-w ◽

2021 ◽

Author(s):

Pierre Tulet ◽

Bertrand Aunay ◽

Guilhem Barruol ◽

Christelle Barthe ◽

Remi Belon ◽

...

Keyword(s):

Indian Ocean ◽

West Indian ◽

Ocean Basin ◽

Transport Processes ◽

The South ◽

South West Indian Ocean ◽

South West ◽

The Face ◽

West Indian Ocean ◽

Solid Transport

AbstractToday, resilience in the face of cyclone risks has become a crucial issue for our societies. With climate change, the risk of strong cyclones occurring is expected to intensify significantly and to impact the way of life in many countries. To meet some of the associated challenges, the interdisciplinary ReNovRisk programme aims to study tropical cyclones and their impacts on the South-West Indian Ocean basin. This article is a presentation of the ReNovRisk programme, which is divided into four areas: study of cyclonic hazards, study of erosion and solid transport processes, study of water transfer and swell impacts on the coast, and studies of socio-economic impacts. The first transdisciplinary results of the programme are presented together with the database, which will be open access from mid-2021.

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Diversity and Geographical Structure of Xanthomonas citri pv. citri on Citrus in the South West Indian Ocean Region

Microorganisms ◽

10.3390/microorganisms9050945 ◽

2021 ◽

Vol 9 (5) ◽

pp. 945

Author(s):

Olivier Pruvost ◽

Damien Richard ◽

Karine Boyer ◽

Stéphanie Javegny ◽

Claudine Boyer ◽

...

Keyword(s):

Indian Ocean ◽

Host Range ◽

Disease Surveillance ◽

West Indian ◽

Copper Resistance ◽

The South ◽

South West Indian Ocean ◽

South West ◽

Strain Collection ◽

West Indian Ocean

A thorough knowledge of genotypic and phenotypic variations (e.g., virulence, resistance to antimicrobial compounds) in bacteria causing plant disease outbreaks is key for optimizing disease surveillance and management. Using a comprehensive strain collection, tandem repeat-based genotyping techniques and pathogenicity assays, we characterized the diversity of X. citri pv. citri from the South West Indian Ocean (SWIO) region. Most strains belonged to the prevalent lineage 1 pathotype A that has a wide host range among rutaceous species. We report the first occurrence of genetically unrelated, nonepidemic lineage 4 pathotype A* (strains with a host range restricted to Mexican lime and related species) in Mauritius, Moheli and Réunion. Microsatellite data revealed that strains from the Seychelles were diverse, grouped in three different clusters not detected in the Comoros and the Mascarenes. Pathogenicity data suggested a higher aggressiveness of strains of one of these clusters on citron (Citrus medica). With the noticeable exception of the Comoros, there was no sign of recent interisland movement of the pathogen. Consistent with this finding, the copL gene, a marker for the plasmid-borne copLAB copper resistance that was recently identified in Réunion, was not detected in 568 strains from any islands in the SWIO region apart from Réunion.

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