Jane M Edgeloe, Samuel Starko, Albert Pessarrodona, Melinda A Coleman, Jacqueline Batley, Thomas Wernberg, Georgina V Wood
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引用次数: 0
Abstract
Temperate seaweed forests are among the most productive and widespread habitats in coastal waters. However, they are under threat from climate change and other anthropogenic stressors. To effectively conserve and manage these ecosystems under these rising pressures, an understanding of the genetic diversity and structure of habitat-forming seaweeds will be necessary. Australia's Great Southern Reef, a global hotspot of endemic diversity, is home to one of the world's most speciose habitat-forming seaweed genera, Cystophora (order Fucales). Despite severe declines in some species, genomic data on this genus remain limited. We used a reduced representation genomic approach (DaRTSeq) to investigate the genetic diversity and structure of Cystophora racemosa, a dominant canopy-forming species, across ~850 km of its range. Our sequencing captured 4741 high-quality single nucleotide polymorphisms (SNPs), and we distinguished neutral loci from those under natural selection (i.e., outlier loci). We identified strong population structure and high genetic differentiation for both neutral (mean FST = 0.404) and outlier loci (mean FST = 0.901). Across populations, genetic diversity was low (neutral: mean HE = 0.046; outlier: HE = 0.042), with high inferred inbreeding (neutral loci mean FIS = 0.531) and no evidence of isolation-by-distance. Several SNPs (n = 70) were observed to be putatively adaptive, with most (97%) correlated with annual maximum sea surface temperature (SST, °C), indicating local adaptation to this key ocean variable. Our results show that C. racemosa populations have low genetic diversity and high differentiation, both of which may increase the vulnerability of this important foundation species to global change.
期刊介绍:
The Journal of Phycology was founded in 1965 by the Phycological Society of America. All aspects of basic and applied research on algae are included to provide a common medium for the ecologist, physiologist, cell biologist, molecular biologist, morphologist, oceanographer, taxonomist, geneticist, and biochemist. The Journal also welcomes research that emphasizes algal interactions with other organisms and the roles of algae as components of natural ecosystems.
All aspects of basic and applied research on algae are included to provide a common medium for the ecologist, physiologist, cell biologist, molecular biologist, morphologist, oceanographer, acquaculturist, systematist, geneticist, and biochemist. The Journal also welcomes research that emphasizes algal interactions with other organisms and the roles of algae as components of natural ecosystems.