biostudies-literatureBernard MAgence Nationale de la RechercheNatural Environment Research CouncilH2020 Marie Skłodowska-Curie Actions2901-2911https://www.ebi.ac.uk/biostudies/studies/S-EPMC6208874biostudies-literatureUnknown30(5)Morphological changes-such as dark spots, twisted stipes and deformed blades-have been observed in wild and cultivated <i>Saccharina latissima</i>. The putative cause for the disease symptoms is the filamentous endophytic brown alga <i>Laminarionema elsbetiae</i>, which is known to invade stipes and fronds of its hosts. Little is known about this interaction and its occurrence in the field, although former studies indicated high endophyte prevalence in kelp populations. Previous epidemiological studies on kelp endophytes were mainly based on the examination of microscopic sections, followed by time-consuming isolation and cultivation steps in order to identify the endophyte and a reliable method to quantify endophyte infections was missing. As a novel approach, we established and validatedJournal of applied phycologyqPCR-based relative quantification of the brown algal endophyte <i>Laminarionema elsbetiae</i> in <i>Saccharina latissima</i>: variation and dynamics of host-endophyte interactions.PMC6208874ANR-10-BTBR-04642575NE/L013223/1Jacquemin BBernard MBallenghien MLeblanc CRousvoal SPeters AFfalseqPCR-based relative quantification of the brown algal endophyte <i>Laminarionema elsbetiae</i> in <i>Saccharina latissima</i>: variation and dynamics of host-endophyte interactions.Morphological changes-such as dark spots, twisted stipes and deformed blades-have been observed in wild and cultivated <i>Saccharina latissima</i>. The putative cause for the disease symptoms is the filamentous endophytic brown alga <i>Laminarionema elsbetiae</i>, which is known to invade stipes and fronds of its hosts. Little is known about this interaction and its occurrence in the field, although former studies indicated high endophyte prevalence in kelp populations. Previous epidemiological studies on kelp endophytes were mainly based on the examination of microscopic sections, followed by time-consuming isolation and cultivation steps in order to identify the endophyte and a reliable method to quantify endophyte infections was missing. As a novel approach, we established and validated2018-01-01T00:00:00Z20182026-07-16T05:52:35.002Z2019-03-27T00:09:36ZS-EPMC62088743041625910.1007/s10811-017-1367-0