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1.
Ecol Lett ; 27(9): e14514, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39354913

RESUMO

The efficient conversion of tissues into reproductive success is a crucial aspect affecting the evolution of life histories. Masting, the interannually variable and synchronous seed production in perennial plants, is a strategy that can enhance reproductive efficiency by mitigating seed predation and pollen limitation. However, evaluating benefits is insufficient to establish whether efficiency has improved, as such assessments neglect the associated costs of masting, particularly during the critical seed-to-seedling stage. We conducted a parentage analysis of seedlings and adults in a population of 209 Sorbus aucuparia trees, monitored over 23 years, providing pioneering documentation of the effects of masting on the fitness of individual trees beyond the seed stage. Our results show high costs of interannual variation that can be mitigated by high synchrony and reveal the existence of phenotypes that appear to reap the benefits of masting while avoiding its costs through regular reproduction.


Assuntos
Plântula , Sorbus , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Sorbus/fisiologia , Reprodução , Sementes/crescimento & desenvolvimento , Sementes/fisiologia , Frutas/crescimento & desenvolvimento , Frutas/fisiologia
2.
Mol Biol Rep ; 51(1): 210, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38270754

RESUMO

BACKGROUND: Masked Bobwhite (Colinus virginianus ridgwayi) is a critically-endangered New World quail species endemic to Sonoran Desert grasslands of North America. It suffered severe population declines during the nineteenth and twentieth centuries, with its persistence now reliant upon a captive breeding program that requires careful genetic management to maintain extant genetic diversity. Although nuclear microsatellite DNA markers existed for the closely related Northern Bobwhite (C. virginianus), none were available for Masked Bobwhite to inform necessary management decisions. METHODS AND RESULTS: Paired-end Illumina© sequencing was conducted to screen the Masked Bobwhite genome for microsatellite loci. We identified 18 loci exhibiting high polymorphism and limited deviations from genetic equilibrium expectations. These loci were amplified in 78 individuals. Familial relationships were reconstructed via sibship methods and compared to manually-curated pedigree data. Thirteen of fifteen full-sibling groups in the pedigree were exactly reconstructed (86.6%). Three other full-sibling groups partially matched pedigree relationships with high statistical confidence, and likely represented pedigree inaccuracies. Four additional full-sibling pairs were identified with low statistical confidence and likely resulted from analytical artifacts. CONCLUSIONS: The novel microsatellite loci accurately reconstructed parent-offspring and sibling relationships. These loci will be useful for guiding genetic management decisions and identifying pedigree inaccuracies in the captive breeding program.


Assuntos
Colinus , Humanos , Animais , Cruzamento , Espécies em Perigo de Extinção , Repetições de Microssatélites/genética , América do Norte
3.
Mol Biol Rep ; 50(5): 4145-4154, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36877349

RESUMO

BACKGROUND: The green sea turtle, Chelonia mydas, is a migratory species with a strong natal homing behavior leading to a complex population structure worldwide. The species has suffered severe declines in local populations; it is therefore crucial to understand its population dynamics and genetic structure to adopt appropriate management policies. Here, we describe the development of 25 new microsatellite markers specific to C. mydas and suitable for these analyses. METHODS AND RESULTS: They were tested on 107 specimens from French Polynesia. An average allelic diversity of 8 alleles per locus was reported and observed heterozygosity ranged from 0.187 to 0.860. Ten loci were significantly deviant from the Hardy-Weinberg equilibrium, and 16 loci showed a moderate to high level of linkage disequilibrium (4-22%). The overall Fis was positive (0.034, p-value < 0.001), and sibship analysis revealed 12 half- or full-sibling dyads, suggesting possible inbreeding in this population. Cross-amplification tests were performed on two other marine turtle species, Caretta caretta and Eretmochelys imbricata. All loci successfully amplified on these two species, though 1 to 5 loci were monomorphic. CONCLUSION: These new markers will not only be relevant for further analyses on the population structure of the green turtle and the two other species, but they will also be invaluable for parentage studies, for which a high number of polymorphic loci are necessary. This can provide important insight into male reproductive behavior and migration, an aspect of sea turtle biology that is of critical importance for the conservation of the species.


Assuntos
Tartarugas , Animais , Masculino , Tartarugas/genética , Heterozigoto , Repetições de Microssatélites/genética , Polinésia
4.
J Hered ; 114(3): 259-270, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37002622

RESUMO

Hibiscus liliiflorus, endemic to the Indian Ocean island of Rodrigues, is one of the rarest plant species in the world; only 2 wild individuals remain. Previously, when 4 wild individuals remained, the Mauritian Wildlife Foundation (MWF) in Rodrigues propagated cuttings of them in their nursery, then planted seedlings produced in the nursery into 3 outplanted populations on the island. Our goals were to: 1) assess whether all 4 original wild genotypes are represented in the MWF nursery; 2) determine whether ex situ living collections at international botanical gardens maintain unique genotypes of H. liliiflorus; 3) assess whether nursery individuals have crossed or self-fertilized to produce seed and quantify their relative contributions to outplanted populations; and 4) provide recommendations for future conservation actions. We used a 2b-RADseq approach to produce 2,711 genome-wide single nucleotide polymorphisms (SNPs) from 98 samples. Genotype identity analysis, principal component analysis, and model-based clustering in STRUCTURE found 4 genotypes extant in Rodrigues but no unique genotypes in ex situ botanic garden collections. Only 3 genotypes are represented in the MWF nursery; the one remaining genotype is represented by an extant wild individual. Parentage analysis showed that seeds produced in the MWF nursery resulted from both self-fertilization and crossing between genotypes, a result supported by internal relatedness and hybrid index calculations. Each outplanted population is dominated by a subset of parental genotypes, and we propose actions to balance the parental contributions to outplanted populations. Our study highlights how genetic assessments of ex situ conservation projects help conserve critically endangered species.


Assuntos
Conservação dos Recursos Naturais , Hibiscus , Humanos , Animais , Hibiscus/genética , Espécies em Perigo de Extinção , Plantas , Genótipo
5.
Mol Ecol ; 31(11): 3072-3082, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35403317

RESUMO

Larval exchange among marine populations is a vital driver of population dynamics and has the potential to inform conservation actions, but accurately measuring dispersal remains challenging. Consequently, empirical dispersal kernels have been measured for only a few marine species. Here, we obtained indirect dispersal estimates using an isolation-by-distance (IBD) model in the coral reef fish Elacatinus lori and assessed the accuracy of these estimates by comparing them to direct measurements of dispersal from genetic parentage analysis. Specifically, drawing on the IBD slope and effective population density, we indirectly estimated sigma (σ), the spread of a dispersal distribution. While the spread of the directly measured distribution was σ = 3.93 km (95% CI: 3.29-4.71 km), the spread of the IBD distribution was σ = 4.10 km (95% CI: 3.23-5.03) and σ = 2.90 km (95% CI: 2.26-3.59), assuming a random or monogamous mating system, respectively. Parameterizing Laplace dispersal kernels with these values of σ yielded patterns that were remarkably similar to a kernel fit to the direct parentage data. We also found that, like many marine fishes, E. lori has a large effective population size. However, uncertainty in effective size did not ultimately have a strong effect on the IBD-based dispersal estimates. Taken together, these findings illustrate that accurate dispersal estimates can be produced by indirect IBD methods and suggest that this more feasible approach to estimating dispersal may be broadly applicable to the study of marine larval dispersal.


Assuntos
Recifes de Corais , Perciformes , Animais , Peixes/genética , Larva/genética , Perciformes/genética , Dinâmica Populacional
6.
J Evol Biol ; 35(6): 831-843, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35567785

RESUMO

Historical events of population fragmentation, expansion and admixture over geological time may result in complex patterns of reproductive isolation and may explain why, for some taxa, the study of mitochondrial (mt) and nuclear (nu) genetic data results in discordant evolutionary patterns. Complex patterns of taxonomic diversity were recently revealed in earthworms for which distribution is largely the result of paleogeographical events. Here, we investigated reproductive isolation patterns in a complex of cryptic species of earthworms in which discordant patterns between mt and nu genetic lineages were previously revealed, the Allolobophora chlorotica aggregate. Using four nu microsatellite markers and a fragment of the cytochrome c oxidase subunit I mt gene, we carried out a parentage analysis to investigate the mating patterns (i) between individuals belonging to two divergent mt lineages that cannot be distinguished with nu markers and (ii) between individuals belonging to lineages that are differentiated both at the mt and nu levels. Amongst the 157 field-collected individuals, 66 adults were used in cross-breeding experiments to form 22 trios based on their assignment to a mt lineage, and 453 obtained juveniles were genotyped. We showed that adults that mated with both their potential mates in the trio produced significantly more juveniles. In crosses between lineages that diverged exclusively at the mt level, a sex-specific pattern of reproduction characteristic to each lineage was observed, suggesting a possible conflict of interest concerning the use of male/female function between mating partners. In crosses between lineages that diverged both at the mt and nu levels, a high production of cocoons was counterbalanced by a low hatching rate, suggesting a post-zygotic reproductive isolation. Different degrees of reproductive isolation, from differential sex allocation to post-zygotic isolation, were thus revealed. Lineages appear to be at different stages in the speciation process, which likely explain the observed opposite patterns of mitonuclear congruence.


Assuntos
Oligoquetos , Isolamento Reprodutivo , Animais , DNA Mitocondrial/genética , Feminino , Humanos , Masculino , Repetições de Microssatélites , Oligoquetos/genética , Filogenia
7.
Biol Lett ; 18(5): 20210576, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35506241

RESUMO

While mouthbrooding is not an uncommon parental care strategy in fishes, paternal mouthbrooding only occurs in eight fish families and is little studied. The high cost of paternal mouthbrooding to the male implies a low risk of investment in another male's offspring but genetic parentage patterns are poorly known for paternal mouthbrooders. Here, we used single-nucleotide polymorphism genetic data to investigate parentage relationships of broods of two mouthbrooders of northern Australian rivers, mouth almighty Glossamia aprion and blue catfish Neoarius graeffei. For N. graeffei, we found that the parentage pattern was largely monogamous with the brooder male as the sire. For G. aprion, the parentage pattern was more heterogeneous including observations of monogamous broods with the brooder male as the sire (73%), polygyny (13%), cuckoldry (6%) and a brood genetically unrelated to the brooder male (6%). Findings demonstrate the potential for complex interrelationships of male care, paternity confidence and mating behaviour in mouthbrooding fishes.


Assuntos
Reprodução , Comportamento Sexual Animal , Animais , Austrália , Peixes , Humanos , Masculino , Comportamento Paterno
8.
Int J Mol Sci ; 23(1)2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35008920

RESUMO

The objective of the present research was to study the effect of cold shock (3 °C and 6 °C) on fertilized eggs of the sterlet, Acipenser ruthenus L. Cold shock was applied for various durations (30, 60 and 90 min) and the ploidy levels, survival, and genotypes of the treated embryos/larvae were recorded. Analysis of ploidy levels confirmed the presence of diploid, triploid, and mosaic (1n/2n, 2n/3n, and 1n/2n/3n) genotypes in experimental groups, while it was strictly diploid in control groups. Microsatellite genotyping confirmed both the incidence of polyspermy and retention of the 2nd polar body in experimental groups. However, patterns of inheritance in all diploid offspring in experimental and control groups revealed classical Mendelian disomic inheritance. Interestingly, the observed mosaic sterlets had normal morphology and were alive. However, some larvae had abnormal morphology which may be due to haploid syndrome. In all treatment groups (treatments: 3 °C-30 min; 3 °C-60 min; 3 °C-90 min; 6 °C-60 min), where the percentage of polyploid/mosaic larvae were high, the mortality was also high. Whereas, in the control groups (where there were only diploid (2n) larvae), the mortality was relatively low.


Assuntos
Resposta ao Choque Frio/fisiologia , Peixes/crescimento & desenvolvimento , Peixes/genética , Ploidias , Alelos , Animais , Segregação de Cromossomos , Desenvolvimento Embrionário , Peixes/embriologia , Larva/crescimento & desenvolvimento , Repetições de Microssatélites/genética , Análise de Sobrevida
9.
J Anim Ecol ; 90(1): 197-211, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32772372

RESUMO

Mating behaviour and the timing of reproduction can inhibit genetic exchange between closely related species; however, these reproductive barriers are challenging to measure within natural populations. Social network analysis provides promising tools for studying the social context of hybridization, and the exchange of genetic variation, more generally. We test how social networks within a hybrid population of California Callipepla californica and Gambel's quail Callipepla gambelii change over discrete periods of a breeding season. We assess patterns of phenotypic and genotypic assortment, and ask whether altered associations between individuals (association rewiring), or changes to the composition of the population (individual turnover) drive network dynamics. We use genetic data to test whether social associations and relatedness between individuals correlate with patterns of parentage within the hybrid population. To achieve these aims, we combine RFID association data, phenotypic data and genomic measures with social network analyses. We adopt methods from the ecological network literature to quantify shifts in network structure and to partition changes into those due to individual turnover and association rewiring. We integrate genomic data into networks as node-level attributes (ancestry) and edges (relatedness, parentage) to test links between social and parentage networks. We show that rewiring of associations between individuals that persist across network periods, rather than individual turnover, drives the majority of the changes in network structure throughout the breeding season, and that the traits involved in phenotypic/genotypic assortment were highly dynamic over time. Social networks were randomly assorted based on genetic ancestry, suggesting weak behavioural reproductive isolation within this hybrid population. Finally, we show that the strength of associations within the social network, but not levels of genetic relatedness, predicts patterns of parentage. Social networks play an important role in population processes such as the transmission of disease and information, yet there has been less focus on how networks influence the exchange of genetic variation. By integrating analyses of social structure, phenotypic assortment and reproductive outcomes within a hybrid zone, we demonstrate the utility of social networks for analysing links between social context and gene flow within wild populations.


Assuntos
Fluxo Gênico , Hibridização Genética , Animais , Genótipo , Fenótipo , Rede Social
10.
Mol Biol Rep ; 48(7): 5787-5793, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34269970

RESUMO

BACKGROUD: Trichoglossus haematodus is the most popular parrots globally and one of the most bred species in Korea's zoos. However, despite its popularity, there are limited studies on the population genetics of this species. METHODS AND RESULTS: In this study, 10 polymorphic microsatellite markers were developed for T. haematodus. The number of alleles ranged from 6 to 9 (mean 7.9). Null alleles were present in two loci (TH-07 and TH-08). The observed heterozygosity ranged from 0.4444 to 1.0000 (mean 0.7000). One locus (TH-08) indicated a significant deviation from the Hardy-Weinberg equilibrium after Bonferroni correction (p < 0.005). The mean inbreeding coefficient (FIS) of the 10 loci was positive, suggesting that there is inbreeding in the population. Since the polymorphism information content (PIC) values were more than 0.7 in all loci, all markers developed in this study were classified as informative. The parentage exclusion probabilities considering all loci were higher than 0.99 in all three cases (P1, P2, and P3). The cross-species amplification of the 10 markers was tested in T. moluccanus, a close relative species of T. haematodus. These markers were also informative for T. moluccanus with PIC values higher than 0.7 in all loci. Additionally, the parentage exclusion probabilities (P1, P2 and P3) for T. moluccanus were above 0.99. However, due to the small number of T. haematodus and T. moluccanus investigated in this study, the 10 microsatellite markers should be analyzed with more individuals of these two species in future studies. CONCLUSIONS: The markers developed in this study might be helpful for investigations of genetic diversity and parentage analysis of T. haematodus and T. moluccanus.


Assuntos
Genética Populacional , Repetições de Microssatélites , Papagaios/classificação , Papagaios/genética , Polimorfismo Genético , Animais , Cruzamentos Genéticos , Loci Gênicos , Sequenciamento de Nucleotídeos em Larga Escala
11.
Breed Sci ; 71(2): 253-260, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34377073

RESUMO

Oil palm is continually being improved via controlled crossing of selected palms to ensure sustainable yields and productivity. As such, correct parental assignment is important as the presence of illegitimates will compromise the progress of improvement. In the present study, we determined the optimal number of microsatellite (SSR) markers for detection of illegitimates in selected oil palm crosses with high confidence. Determining the optimal number of markers to assign parentage will ensure that the DNA fingerprinting will be cost effective for routine use as a quality control tool in oil palm improvement programs. Here, we evaluated a wide range of crosses that included a cross derived from wild germplasm palm. The results revealed that markers with high PIC are informative and detect most of the alleles present in a cross, including those exhibited by the illegitimates. A larger number of optimum sets of markers are needed to detect all illegitimates for crosses with higher levels of genetic diversity. The optimal number of polymorphic SSR markers determined in the present study can ensure that appropriate quality control is implemented for oil palm improvement programs.

12.
Breed Sci ; 71(5): 594-600, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35087323

RESUMO

Tea cultivars have been bred by individual selection of landraces and by crossbreeding, but the validation of the parentage is limited. In this study, we performed parentage analysis of 79 tea cultivars in Japan based on SSR markers to confirm or identify the parent-offspring relationships among them. The effectiveness of nine SSR markers for parentage analysis was validated by comparing them to the existing cleaved amplified polymorphic sequence markers. The former markers were detectable more alleles than the latter. Simulation of parentage analysis of the tea cultivars predicted biparental origins for 12 cultivars ('Houshun', 'Mie ryokuhou no. 1', 'Surugawase', 'Tenmyo', 'Yamanoibuki', 'Harumidori', 'Koushun', 'Minekaori', 'Okumusashi', 'Saemidori', 'Sofu', and 'Toyoka'), in the first five of which candidate parents of yet-to-be-defined pedigree were newly identified. Comparisons of a total of 41 SSR genotypes confirmed the newly-identified parentages of 'Asahi' for 'Tenmyo', 'Rokurou' for 'Houshun', 'Surugawase', and 'Yamanoibuki', and 'Yamatomidori' for 'Mie ryokuhou no. 1'. The maternity of seven cultivars out of the 12 was also confirmed with chloroplast DNA sequences. Uniparental origins were confirmed for 25 cultivars. This parentage analysis has improved our knowledge of tea pedigrees and will aid in the development of new cultivars.

13.
BMC Plant Biol ; 20(1): 2, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31898487

RESUMO

BACKGROUND: Apple (Malus x domestica Borkh.) is one of the most important fruit tree crops of temperate areas, with great economic and cultural value. Apple cultivars can be maintained for centuries in plant collections through grafting, and some are thought to date as far back as Roman times. Molecular markers provide a means to reconstruct pedigrees and thus shed light on the recent history of migration and trade of biological materials. The objective of the present study was to identify relationships within a set of over 1400 mostly old apple cultivars using whole-genome SNP data (~ 253 K SNPs) in order to reconstruct pedigrees. RESULTS: Using simple exclusion tests, based on counting the number of Mendelian errors, more than one thousand parent-offspring relations and 295 complete parent-offspring families were identified. Additionally, a grandparent couple was identified for the missing parental side of 26 parent-offspring pairings. Among the 407 parent-offspring relations without a second identified parent, 327 could be oriented because one of the individuals was an offspring in a complete family or by using historical data on parentage or date of recording. Parents of emblematic cultivars such as 'Ribston Pippin', 'White Transparent' and 'Braeburn' were identified. The overall pedigree combining all the identified relationships encompassed seven generations and revealed a major impact of two Renaissance cultivars of French and English origin, namely 'Reinette Franche' and 'Margil', and one North-Eastern Europe cultivar from the 1700s, 'Alexander'. On the contrary, several older cultivars, from the Middle Ages or the Roman times, had no, or only single, identifiable offspring in the set of studied accessions. Frequent crosses between cultivars originating from different European regions were identified, especially from the nineteenth century onwards. CONCLUSIONS: The availability of over 1400 apple genotypes, previously filtered for genetic uniqueness and providing a broad representation of European germplasm, has been instrumental for the success of this large pedigree reconstruction. It enlightens the history of empirical selection and recent breeding of apple cultivars in Europe and provides insights to speed-up future breeding and selection.


Assuntos
Genoma de Planta , Malus/genética , Polimorfismo de Nucleotídeo Único/genética , Cruzamento , Europa (Continente) , Genótipo , Técnicas de Genotipagem/métodos , Linhagem , Sequenciamento Completo do Genoma
14.
Mol Biol Rep ; 47(1): 727-729, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31677035

RESUMO

Mating plays key roles in the demographic and genetic dynamics of populations. Estimates of mating portfolios and system based on progeny array (PA) method required highly polymorphic genetic markers, of which microsatellite is a good choice. In this study, we reported 19 polymorphic microsatellite loci for Aconitum gymnandrum. The number of alleles per locus ranged from 2 to 12. Observed and expected heterozygosity ranged from 0.000 to 1.000 and from 0.219 to 0.842, respectively. Seven loci showed significant deviation from Hardy-Weinberg equilibrium. These markers will provide a useful tool for pollination ecology and population genetic studies of A. gymnandrum in Qinghai-Tibet plateau.


Assuntos
Aconitum/classificação , Aconitum/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Repetições de Microssatélites/genética , DNA de Plantas/análise , DNA de Plantas/genética , Marcadores Genéticos/genética , Genética Populacional/métodos
15.
Mol Biol Rep ; 47(8): 6417-6427, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32607954

RESUMO

Agapornis are a group of small African parrots that are heavily traded around the world. They are invasive species in many places, but some of them are listed as Vulnerable or Near Threatened. However, the genetic tools for assessing inter-individual relationships, population structure, and genetic diversity of these birds are very limited. Therefore, we developed polymorphic microsatellite markers in A. roseicollis and tested the transferability on 5 lovebird species including A. personatus, A. nigrigenis, A. fischeri, A. pullarius, and A. canus, and two closely related outgroups (i.e. Bolbopsittacus lunulatus and Loriculus galgulus). We first performed whole-genome re-sequencing on five individuals of A. roseicollis to identify potential polymorphic loci. Out of 37 loci tested in 11 A. roseicollis, 27 loci were demonstrated to be polymorphic, with the number of the alleles ranging from 2 to 7 (mean = 3.963). The observed heterozygosity ranged from 0 to 0.875 (mean = 0.481) and expected heterozygosity ranged from 0.233 to 0.842 (mean = 0.642). Five loci (Agro-A13, p < 0.01; Agro-A15, p < 0.05; Agro-A43, p < 0.05, Agro-A65, p < 0.05; Agro-A67, p < 0.05) were detected to deviate from Hardy-Weinberg equilibrium, with the presence of null alleles suggested in locus Agro-A13 and Agro-A77. The exclusion powers for PE1 and PE2 are 0.997 and 0.999, respectively. The 27 novel polymorphic markers developed here will be useful for parentage and kinship assignment and population genetics study in Agapornis, and provide a tool for scientific research, captive breeding industry, and invasion and conservation management of these species.


Assuntos
Agapornis/genética , Repetições de Microssatélites , Animais , Cruzamento , Espécies em Perigo de Extinção , Heterozigoto , Sequenciamento de Nucleotídeos em Larga Escala , Polimorfismo Genético , Sequenciamento Completo do Genoma
16.
BMC Bioinformatics ; 20(1): 108, 2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-30819089

RESUMO

BACKGROUND: The accurate determination of parent-progeny relationships within both in situ natural populations and ex situ genetic resource collections can greatly enhance plant breeding/domestication efforts and support plant genetic resource conservation strategies. Although a range of parentage analysis tools are available, none are designed to infer such relationships using genome-wide single nucleotide polymorphism (SNP) data in the complete absence of guiding information, such as generational groups, partial pedigrees, or genders. The R package ('apparent') developed and presented here addresses this gap. RESULTS: 'apparent' adopts a novel strategy of parentage analysis based on a test of genetic identity between a theoretically expected progeny (EPij), whose genotypic state can be inferred at all homozygous loci for a pair of putative parents (i and j), and all potential offspring (POk), represented by the k individuals of a given germplasm collection. Using the Gower Dissimilarity metric (GD), genetic identity between EPij and POk is taken as evidence that individuals i and j are the true parents of offspring k. Significance of a given triad (parental pairij + offspringk) is evaluated relative to the distribution of all GDij|k values for the population. With no guiding information provided, 'apparent' correctly identified the parental pairs of 15 lines of known pedigree within a test population of 77 accessions of Actinidia arguta, a performance unmatched by five other commonly used parentage analysis tools. In the case of an inconclusive triad analysis due to the absence of one parent from the test population, 'apparent' can perform a subsequent dyad analysis to identify a likely single parent for a given offspring. Average dyad analysis accuracy was 73.3% in the complete absence of pedigree information but increased to 100% when minimal generational information (adults vs. progeny) was provided. CONCLUSIONS: The 'apparent' R package is a fast and accurate parentage analysis tool that uses genome-wide SNP data to identify parent-progeny relationships within populations for which no a priori knowledge of family structure exists.


Assuntos
Plantas/genética , Polimorfismo de Nucleotídeo Único/genética , Software , Actinidia/genética , Loci Gênicos , Genótipo , Melhoramento Vegetal , Fatores de Tempo
17.
Mol Ecol ; 28(12): 3119-3134, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31141237

RESUMO

The natural regeneration of tree species depends on seed and pollen dispersal. To assess whether limited dispersal could be critical for the sustainability of selective logging practices, we performed parentage analyses in two Central African legume canopy species displaying contrasted floral and fruit traits: Distemonanthus benthamianus and Erythrophleum suaveolens. We also developed new tools linking forward dispersal kernels with backward migration rates to better characterize long-distance dispersal. Much longer pollen dispersal in D. benthamianus (mean distance dp  = 700 m, mp  = 52% immigration rate in 6 km2 plot, s = 7% selfing rate) than in E. suaveolens (dp  = 294 m, mp  = 22% in 2 km2 plot, s = 20%) might reflect different insect pollinators. At a local scale, secondary seed dispersal by vertebrates led to larger seed dispersal distances in the barochorous E. suaveolens (ds  = 175 m) than in the wind-dispersed D. benthamianus (ds  = 71 m). Yet, seed dispersal appeared much more fat-tailed in the latter species (15%-25% seeds dispersing >500 m), putatively due to storm winds (papery pods). The reproductive success was correlated to trunk diameter in E. suaveolens and crown dominance in D. benthamianus. Contrary to D. benthamianus, E. suaveolens underwent significant assortative mating, increasing further the already high inbreeding of its juveniles due to selfing, which seems offset by strong inbreeding depression. To achieve sustainable exploitation, seed and pollen dispersal distances did not appear limiting, but the natural regeneration of E. suaveolens might become insufficient if all trees above the minimum legal cutting diameter were exploited. This highlights the importance of assessing the diameter structure of reproductive trees for logged species.


Assuntos
Fabaceae/crescimento & desenvolvimento , Pólen/crescimento & desenvolvimento , Reprodução/genética , Dispersão de Sementes/genética , Fabaceae/genética , Frutas/genética , Frutas/crescimento & desenvolvimento , Fluxo Gênico , Genética Populacional , Endogamia , Repetições de Microssatélites/genética , Polinização/genética , Reprodução/fisiologia , Sementes/genética , Árvores/genética , Árvores/crescimento & desenvolvimento , Vento
18.
Mol Ecol ; 28(7): 1611-1623, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30739378

RESUMO

Marine species with pelagic larvae typically exhibit little population structure, suggesting long-distance dispersal and high gene flow. Directly quantifying dispersal of marine fishes is challenging but important, particularly for the design of marine protected areas (MPAs). Here, we studied kelp rockfish (Sebastes atrovirens) sampled along ~25 km of coastline in a boundary current-dominated ecosystem and used genetic parentage analysis to identify dispersal events and characterize them, because the distance between sedentary parents and their settled offspring is the lifetime dispersal distance. Large sample sizes and intensive sampling are critical for increasing the likelihood of detecting parent-offspring matches in such systems and we sampled more than 6,000 kelp rockfish and analysed them with a powerful set of 96 microhaplotype markers. We identified eight parent-offspring pairs with high confidence, including two juvenile fish that were born inside MPAs and dispersed to areas outside MPAs, and four fish born in MPAs that dispersed to nearby MPAs. Additionally, we identified 25 full-sibling pairs, which occurred throughout the sampling area and included all possible combinations of inferred dispersal trajectories. Intriguingly, these included two pairs of young-of-the-year siblings with one member each sampled in consecutive years. These sibling pairs suggest monogamy, either intentional or accidental, which has not been previously demonstrated in rockfishes. This study provides the first direct observation of larval dispersal events in a current-dominated ecosystem and direct evidence that larvae produced within MPAs are exported both to neighbouring MPAs and to proximate areas where harvest is allowed.


Assuntos
Distribuição Animal , Genética Populacional , Perciformes/genética , Animais , California , Ecossistema , Pesqueiros , Marcadores Genéticos , Haplótipos , Repetições de Microssatélites , Linhagem
19.
Mol Ecol ; 28(7): 1637-1651, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30636347

RESUMO

Ex situ management is an important conservation tool that allows the preservation of biological diversity outside natural habitats while supporting survival in the wild. Captive breeding followed by re-introduction is a possible approach for endangered species conservation and preservation of genetic variability. The Cayman Turtle Centre Ltd was established in 1968 to market green turtle (Chelonia mydas) meat and other products and replenish wild populations, thought to be locally extirpated, through captive breeding. We evaluated the effects of this re-introduction programmme using molecular markers (13 microsatellites, 800-bp D-loop and simple tandem repeat mitochondrial DNA sequences) from captive breeders (N = 257) and wild nesting females (N = 57) (sampling period: 2013-2015). We divided the captive breeders into three groups: founders (from the original stock), and then two subdivisions of F1 individuals corresponding to two different management strategies, cohort 1995 ("C1995") and multicohort F1 ("MCF1"). Loss of genetic variability and increased relatedness was observed in the captive stock over time. We found no significant differences in diversity among captive and wild groups, and similar or higher levels of haplotype variability when compared to other natural populations. Using parentage and sibship assignment, we determined that 90% of the wild individuals were related to the captive stock. Our results suggest a strong impact of the re-introduction programmme on the present recovery of the wild green turtle population nesting in the Cayman Islands. Moreover, genetic relatedness analyses of captive populations are necessary to improve future management actions to maintain genetic diversity in the long term and avoid inbreeding depression.


Assuntos
Cruzamento , Conservação dos Recursos Naturais/métodos , Variação Genética , Genética Populacional , Tartarugas/genética , Animais , DNA Mitocondrial/genética , Espécies em Perigo de Extinção , Feminino , Haplótipos , Repetições de Microssatélites , Índias Ocidentais
20.
J Hered ; 110(3): 351-360, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30726981

RESUMO

A critical part of the sexual selection process in animals is the genetic mating system. Quantifying mating systems, especially in species with cryptic life histories can be challenging. One approach is to use genotypic markers and accurate parentage analysis, along with methods to account for bias when sampling natural populations, to calculate sexual selection metrics derived from Bateman's principles. In this study, 3 microsatellites were used to genotype 48 adults (23 female and 25 male) and 342 offspring from known mothers of live-bearing bluntnose klipfish. Parentage analysis was performed to interpret mating and reproductive success for both sexes. Metrics quantified were the opportunity for selection (I), the opportunity for sexual selection (Is), absolute (ßss), and standardized (ß'ss) Bateman gradients and the maximum intensity of precopulatory sexual selection (s'max). Multiple mating by both sexes were revealed by parentage analysis. However, females did not show significant Bateman gradients or a significant maximum intensity of precopulatory sexual selection (s'max), whereas male sexual selection metrics were all significantly greater than 0. These results suggest a polygynandrous mating system for this species. There is an opportunity for sexual selection to act on males but not females in this population, which is evolutionary tied to anisogamy, parental investment, and sex roles.


Assuntos
Peixes/fisiologia , Preferência de Acasalamento Animal , Reprodução/genética , Comportamento Sexual Animal , Animais , Genótipo , Repetições de Microssatélites , Densidade Demográfica
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