Small-scale turbulence can reduce parasite infectivity to dinoflagellates

mall-scale turbulence and parasite infection are 2 important factors that govern the dynamics and fate of phytoplankton populations. We experimentally investigated the influence of turbulent mixing on the infectivity of the parasite Parvilucifera sinerae to dinoflagellates. Natural phytoplankton com...

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Detalles Bibliográficos
Autor: Llavería, Gisela
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2010
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/321719
Acceso en línea:http://hdl.handle.net/10261/321719
Access Level:acceso abierto
Palabra clave:Medio Marino
dinoflagellates
Centro Oceanográfico de Vigo
Infectivity
Parvilucifera sinerae
Parasite
small-scale turbulence
advection
sinking
buoyancy
environmental factors
Descripción
Sumario:mall-scale turbulence and parasite infection are 2 important factors that govern the dynamics and fate of phytoplankton populations. We experimentally investigated the influence of turbulent mixing on the infectivity of the parasite Parvilucifera sinerae to dinoflagellates. Natural phytoplankton communities were collected during 3 stages of a bloom event in Arenys de Mar Har- bour (NW Mediterranean). The 15 to 60 μm size fraction was used as the inoculum and distributed into spherical flasks. Half of the recipients were exposed to turbulence while the rest were kept still. In the experiments, the dinoflagellate assemblage was mainly composed of Prorocentrum micans, Scrippsiella trochoidea and Alexandrium minutum. We observed a collapse of A. minutum and S. tro- choidea populations in the unshaken flasks, which coincided with an increase in parasite infectivity. After a short exposure to turbulence, the development of the dinoflagellate populations slowed down and stabilised as expected. In the shaken treatments, the infectivity was lower and the decay in the host cells numbers was delayed compared to the still treatments. The degree of interference of the turbulence with infectivity varied among the experiments, due to differences in cell abundances and possibly their physiological state. Results from a numerical model suggest that turbulence could lead to a 25 to 30% decrease in the maximum infection rate, which could be due to host population disper- sion and/or reduced host–parasite contact times. Turbulence may thus be effective in delaying the initial infection, but not in preventing it.