RESUMO
Under the recently adopted Kunming-Montreal Global Biodiversity Framework, 196 Parties committed to reporting the status of genetic diversity for all species. To facilitate reporting, three genetic diversity indicators were developed, two of which focus on processes contributing to genetic diversity conservation: maintaining genetically distinct populations and ensuring populations are large enough to maintain genetic diversity. The major advantage of these indicators is that they can be estimated with or without DNA-based data. However, demonstrating their feasibility requires addressing the methodological challenges of using data gathered from diverse sources, across diverse taxonomic groups, and for countries of varying socio-economic status and biodiversity levels. Here, we assess the genetic indicators for 919 taxa, representing 5271 populations across nine countries, including megadiverse countries and developing economies. Eighty-three percent of the taxa assessed had data available to calculate at least one indicator. Our results show that although the majority of species maintain most populations, 58% of species have populations too small to maintain genetic diversity. Moreover, genetic indicator values suggest that IUCN Red List status and other initiatives fail to assess genetic status, highlighting the critical importance of genetic indicators.
Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Variação Genética , AnimaisRESUMO
Infectious diseases affecting habitat-forming species can have significant impacts on population dynamics and alter the structure and functioning of marine ecosystems. Recently, a fungal infection was described as the causative agent of necrotic lesions on the stipe of the forest-forming macroalga Phyllospora comosa, a disease named "stipe rot" (SR). Here, we developed a quantitative PCR (qPCR) method for rapid detection and quantification of this pathogen, which was applied to evaluate the level of SR infection in eight P. comosa populations spanning the entire latitudinal distribution of this species along southeastern Australia. We also investigated the relationship between the abundance and prevalence of Stipe Rot Fungus (SRF) and potential host chemical defenses as well as its relationship with morphological and ecophysiological traits of P. comosa. qPCR estimates of SRF abundance reflected the levels of infection estimated by visual assessment, with higher numbers of SRF copies being observed in individuals showing high or intermediate levels of visual symptoms of SR. Concordance of conventional PCR and visual assessments was 92 and 94%, respectively, compared to qPCR detection. SRF prevalence was positively related to fucoxanthin content and herbivory, but not significant related to other traits measured (phlorotannin content, total length, thallus diameter, stipe width, number of branches, frond width, fouling, bleaching, gender, and photosynthetic efficiency). These results provide confidence for previous reports of this disease based upon visual assessments only, contribute to the development of monitoring and conservation strategies for safeguarding P. comosa forests, and generate insights into potential factors influencing host-pathogen interactions in this system.