A genome-guided strategy for climate resilience in American chestnut restoration populations

Proceedings of the National Academy of Sciences, Journal Year: 2024, Volume and Issue: 121(30)

Published: July 16, 2024

American chestnut ( Castanea dentata ) is a deciduous tree species of eastern North America that was decimated by the introduction blight fungus Cryphonectria parasitica in early 20th century. Although millions chestnuts survive as root collar sprouts, these trees rarely reproduce. Thus, considered functionally extinct. with improved resistance have been developed through interspecific hybridization followed conspecific backcrossing, and genetic engineering. Incorporating adaptive genomic diversity into backcross families transgenic lines important for restoring across broad climatic gradients. To develop sampling recommendations ex situ conservation wild variation, we coupled whole-genome resequencing 384 stump sprouts genotype–environment association analyses found range can be subdivided three seed zones characterized relatively homogeneous allele frequencies. We estimated 21 to 29 per zone will need conserved capture most extant diversity. also resequenced genomes 269 understand extent which breeding program has already captured diversity, estimate optimal reintroduction sites specific on basis their portfolio future climate projections. Taken together, results inform development an germplasm plan target blight-resistant populations environments provides blueprint developing restoration plans other imperiled species.

Language: Английский

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Strongly deleterious mutations influence reproductive output and longevity in an endangered population

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Sept. 27, 2024

Language: Английский

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Genetic and demographic consequences of range contraction patterns during biological annihilation

Scientific Reports, Journal Year: 2023, Volume and Issue: 13(1)

Published: Jan. 30, 2023

Species range contractions both contribute to, and result from, biological annihilation, yet do not receive the same attention as extinctions. Range can lead to marked impacts on populations but are usually characterized only by reduction in extent of range. For effective conservation, it is critical recognize that all same. We propose three distinct patterns contraction: shrinkage, amputation, fragmentation. tested impact these a generalist species using forward-time simulations. All caused 86-88% population abundance significantly increased average relatedness, with differing declines nucleotide diversity relative contraction pattern. The fragmentation pattern resulted strongest effects post-contraction genetic structure. Defining quantifying their consequences for Earth's biodiversity would provide useful necessary information combat annihilation.

Language: Английский

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Genetic purging in captive endangered ungulates with extremely low effective population sizes

Heredity, Journal Year: 2021, Volume and Issue: 127(5), P. 433 - 442

Published: Sept. 28, 2021

Abstract Inbreeding threatens the survival of small populations by producing inbreeding depression, but also exposes recessive deleterious effects in homozygosis allowing for genetic purging. Using inbreeding-purging theory, we analyze early four pedigreed captive breeding programs endangered ungulates where population growth was prioritized so that most adult females were allowed to contribute offspring according their fitness. We find evidence purging can substantially reduce depression Gazella cuvieri (with effective size N e = 14) and Nanger dama ( 11). No is detected Ammotragus lervia 4), agreement with notion drift overcomes under fast inbreeding, nor G. dorcas 39) where, due larger size, slower detection expected require more generations. Thus, although smaller are always show fitness (as well as less adaptive potential) than ones higher fixation, our results a substantial fraction load be purged when contributions governed natural selection. Since management strategies intended maximize ratio from actual tend purging, search compromise between these could beneficial long term. This achieved either some level random mating role selection determining contributions, or undertaking reintroductions into wild at earliest opportunity.

Language: Английский

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Species-wide genomics of kākāpō provides transformational tools to accelerate recovery

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2022, Volume and Issue: unknown

Published: Oct. 24, 2022

Abstract The kākāpō is a critically endangered, intensively managed, long-lived nocturnal parrot endemic to Aotearoa New Zealand. We generated and analyzed whole-genome sequence data for nearly all individuals living in early 2018 (169 individuals) generate high-quality species-wide genetic variant callset. leverage extensive long-term metadata quantify genome-wide diversity of the species over time present new approaches using probabilistic programming, combined with phenotype dataset spanning five decades, disentangle phenotypic variance into environmental effects while quantifying uncertainty small populations. find associations growth, disease susceptibility, clutch size, egg fertility within genic regions previously shown influence these traits other species. Finally, we breeding values predict illustrate that active management past 45 years has maintained both values, hence, evolutionary potential. provide pathways informing future conservation decisions kākāpō, including prioritizing translocation monitoring poor growth or high risk. Overall, by explicitly addressing challenge sample template inclusion genomic will be transformational recovery efforts around globe.

Language: Английский

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