Mixtures of genotypes increase disease resistance in a coral nursery

Abstract

Marine infectious diseases are a leading cause of population declines globally due, in large part, to challenges in diagnosis and limited treatment options. Mitigating disease spread is particularly important for species targeted for conservation. In some systems, strategic arrangement of organisms in space can constrain disease outbreaks, however, this approach has not been used in marine restoration. Reef building corals have been particularly devastated by disease and continue to experience catastrophic population declines. We show that mixtures of genotypes (i.e., diversity) increased disease resistance in the critically endangered Acropora cervicornis, a species that is frequently targeted for restoration of degraded reefs in the broader Caribbean region. This finding suggests a more generalized relationship between diversity and disease and offers a viable strategy for mitigating the spread of infectious diseases in corals that likely applies to other foundation species targeted for restoration.

Host genetic identity determines parasite community structure across time and space in oyster restoration

“…coastal and estuarine systems with foundation species, such as seagrass meadows, salt marshes and oyster reefs) or as a result of human activities (e.g. agricultural fields, aquaculture farms, early stages of restoration projects with focal species) [8,9,19,28]. Differences in host genetic identity, like those observed among oyster seed sources in this study (electronic supplementary material, appendix S1), can result in intraspecific variation in resistance and/or tolerance traits [27], as well as in behavioural defense mechanisms against parasites [99].…”

“…tolerance [24][25][26]). These differences in host resistance or tolerance can have distinct consequences for hostparasite interactions [27], as well as critical implications for management and conservation [28], especially when host populations provide important ecosystem functions and services [29]. Measuring multiple infection metrics, including both prevalence ( proportion of infected hosts) and intensity ( parasite concentration within infected hosts), can provide insight into the mechanisms underlying host-parasite dynamics (e.g.…”

Concordance of microbial and visual health indicators of white-band disease in nursery reared Caribbean coral Acropora cervicornis

“…The disease signs began in early May 2019 and peaked in July 2019 ( Brown et al, 2022 ). We sampled the microbial communities of the corals shortly after the onset, when only a subset of corals in the entire nursery showed signs of disease.…”

“…1C ). A complete schematic showing the layout of the nursery, including the frames sampled here is available in Brown et al (2022) . Colonies in 2019 were sampled across five genotypes to provide a general description of the microbial changes associated with disease for nursery coral population (2 black, 3 blue, 1 green, 2 red, and 2 yellow).…”