1
|
Fu Q, Deng J, Chen M, Zhong Y, Lu GH, Wang YQ. Population genetic structure and connectivity of a riparian selfing herb Caulokaempferia coenobialis at a fine-scale geographic level in subtropical monsoon forest. BMC PLANT BIOLOGY 2021; 21:329. [PMID: 34238223 PMCID: PMC8265151 DOI: 10.1186/s12870-021-03101-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 06/16/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Rivers and streams facilitate movement of individuals and their genes across the landscape and are generally recognized as dispersal corridors for riparian plants. Nevertheless, some authors have reported directly contrasting results, which may be attributed to a complex mixture of factors, such as the mating system and dispersal mechanisms of propagules (seed and pollen), that make it difficult to predict the genetic diversity and population structure of riparian species. Here, we investigated a riparian self-fertilizing herb Caulokaempferia coenobialis, which does not use anemochory or zoochory for seed dispersal; such studies could contribute to an improved understanding of the effect of rivers or streams on population genetic diversity and structure in riparian plants. Using polymorphic ISSR and cpDNA loci, we studied the effect at a microgeographic scale of different stream systems (a linear stream, a dendritic stream, and complex transverse hydrological system) in subtropical monsoon forest on the genetic structure and connectivity of C. coenobialis populations across Dinghu Mountain (DH) and Nankun Mountain (NK). RESULTS The results indicate that the most recent haplotypes (DH: H7, H8; NK: h6, h7, h11, h12) are not shared among local populations of C. coenobialis within each stream system. Furthermore, downstream local populations do not accumulate genetic diversity, whether in the linear streamside local populations across DH (H: 0.091 vs 0.136) or the dendritic streamside local populations across NK (H: 0.079 vs 0.112, 0.110). Our results show that the connectivity of local C. coenobialis populations across DH and NK can be attributed to historical gene flows, resulting in a lack of spatial genetic structure, despite self-fertilization. Selfing C. coenobialis can maintain high genetic diversity (H = 0.251; I = 0.382) through genetic differentiation (GST = 0.5915; FST = 0.663), which is intensified by local adaptation and neutral mutation and/or genetic drift in local populations at a microgeographic scale. CONCLUSION We suggest that streams are not acting as corridors for dispersal of C. coenobialis, and conservation strategies for maintaining genetic diversity of selfing species should be focused on the protection of all habitat types, especially isolated fragments in ecosystem processes.
Collapse
Affiliation(s)
- Qiong Fu
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Jie Deng
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Min Chen
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Yan Zhong
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Guo-Hui Lu
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Ying-Qiang Wang
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China.
- Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, School of Life Sciences, South China Normal University, Guangzhou, China.
| |
Collapse
|
2
|
Robledo‐Arnuncio JJ, Unger GM. Measuring viability selection from prospective cohort mortality studies: A case study in maritime pine. Evol Appl 2019; 12:863-877. [PMID: 31080501 PMCID: PMC6503825 DOI: 10.1111/eva.12729] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 10/05/2018] [Accepted: 10/15/2018] [Indexed: 11/27/2022] Open
Abstract
By changing the genetic background available for selection at subsequent life stages, stage-specific selection can define adaptive potential across the life cycle. We propose and evaluate here a neutrality test and a Bayesian method to infer stage-specific viability selection coefficients using sequential random genotypic samples drawn from a longitudinal cohort mortality study, within a generation. The approach is suitable for investigating selective mortality in large natural or experimental cohorts of any organism in which individual tagging and tracking are unfeasible. Numerical simulation results indicate that the method can discriminate loci under strong viability selection, and provided samples are large, yield accurate estimates of the corresponding selection coefficients. Genotypic frequency changes are largely driven by sampling noise under weak selection, however, compromising inference in that case. We apply the proposed methods to analyze viability selection operating at early recruitment stages in a natural maritime pine (Pinus pinaster Ait.) population. We measured temporal genotypic frequency changes at 384 candidate-gene SNP loci among seedlings sampled from the time of emergence in autumn until the summer of the following year, a period with high elimination rates. We detected five loci undergoing allele frequency changes larger than expected from stochastic mortality and sampling, with putative functions that could influence survival at early seedling stages. Our results illustrate how new statistical and sampling schemes can be used to conduct genomic scans of contemporary selection on specific life stages.
Collapse
Affiliation(s)
| | - Gregor M. Unger
- Department of Forest Ecology & GeneticsINIA‐CIFORMadridSpain
- Escuela Internacional de DoctoradoUniversidad Rey Juan CarlosMóstolesSpain
- Present address:
Department of Forest GeneticsFederal Research and Training Centre for ForestsNatural Hazards and LandscapeViennaAustria
| |
Collapse
|
3
|
Differential role of a persistent seed bank for genetic variation in early vs. late successional stages. PLoS One 2018; 13:e0209840. [PMID: 30586422 PMCID: PMC6306206 DOI: 10.1371/journal.pone.0209840] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 12/12/2018] [Indexed: 12/03/2022] Open
Abstract
Persistent seed banks are predicted to have an important impact on population genetic processes by increasing effective population size and storing past genetic diversity. Accordingly, persistent seed banks may buffer genetic effects of disturbance, fragmentation and/or selection. However, empirical studies surveying the relationship between aboveground and seed bank genetics under changing environments are scarce. Here, we compared genetic variation of aboveground and seed bank cohorts in 15 populations of the partially cleistogamous Viola elatior in two contrasting early and late successional habitats characterized by strong differences in light-availability and declining population size. Using AFLP markers, we found significantly higher aboveground than seed bank genetic diversity in early successional meadow but not in late successional woodland habitats. Moreover, individually, three of eight woodland populations even showed higher seed bank than aboveground diversity. Genetic differentiation among populations was very strong (фST = 0.8), but overall no significant differentiation could be detected between above ground and seed bank cohorts. Small scale spatial genetic structure was generally pronounced but was much stronger in meadow (Sp-statistic: aboveground: 0.60, seed bank: 0.32) than in woodland habitats (aboveground: 0.11; seed bank: 0.03). Our findings indicate that relative seed bank diversity (i.e. compared to aboveground diversity) increases with ongoing succession and despite decreasing population size. As corroborated by markedly lower small-scale genetic structure in late successional habitats, we suggest that the observed changes in relative seed bank diversity are driven by an increase of outcrossing rates. Persistent seed banks in Viola elatior hence will counteract effects of drift and selection, and assure a higher chance for the species’ long term persistence, particularly maintaining genetic variation in declining populations of late successional habitats and thus enhancing success rates of population recovery after disturbance events.
Collapse
|
4
|
Epperson BK, Li TQ. GENE DISPERSAL AND SPATIAL GENETIC STRUCTURE. Evolution 2017; 51:672-681. [PMID: 28568577 DOI: 10.1111/j.1558-5646.1997.tb03651.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/1996] [Accepted: 02/14/1997] [Indexed: 11/28/2022]
Abstract
Spatial autocorrelation statistics have been studied in theoretical population genetic models and widely used in experimental studies of spatial structure in many plant and animal populations. However, the statistical properties of spatial autocorrelation statistics have remained uncharacterized. Little is known about how values of spatial autocorrelation statistics in population samples depend on the level of dispersal and scheme of sampling. In this paper, we characterize the statistical properties of join-count spatial autocorrelation statistics for population genetic surveys under various conditions of dispersal and sampling. The results indicate generally high statistical power. These results can provide a method to estimate gene dispersal based on standing spatial patterns of genetic variation observed within populations.
Collapse
Affiliation(s)
- Bryan K Epperson
- Department of Forestry, Michigan State University, East Lansing, Michigan, 48824
| | - Tian-Quan Li
- Department of Forestry, Michigan State University, East Lansing, Michigan, 48824
| |
Collapse
|
5
|
Epperson BK, Alvarez-Buylla ER. LIMITED SEED DISPERSAL AND GENETIC STRUCTURE IN LIFE STAGES OF CECROPIA OBTUSIFOLIA. Evolution 2017; 51:275-282. [PMID: 28568800 DOI: 10.1111/j.1558-5646.1997.tb02409.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/1996] [Accepted: 07/03/1996] [Indexed: 11/30/2022]
Affiliation(s)
- Bryan K Epperson
- Department of Forestry, Michigan State University, East Lansing, Michigan, 48824
| | | |
Collapse
|
6
|
Abstract
We study the genealogical structure of samples from a population for which any given generation is made up of direct descendants from several previous generations. These occur in nature when there are seed banks or egg banks allowing an individual to leave offspring several generations in the future. We show how this temporal structure in the reproduction mechanism causes a decrease in the coalescence rate. We also investigate the effects of age-dependent neutral mutations. Our main result gives weak convergence of the scaled ancestral process, with the usual diffusion scaling, to a coalescent process which is equivalent to a time-changed version of Kingman's coalescent.
Collapse
|
7
|
Roberts DG, Ottewell KM, Whelan RJ, Ayre DJ. Is the post-disturbance composition of a plant population determined by selection for outcrossed seedlings or by the composition of the seedbank? Heredity (Edinb) 2013; 112:409-14. [PMID: 24281549 DOI: 10.1038/hdy.2013.119] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Revised: 09/27/2013] [Accepted: 10/08/2013] [Indexed: 11/09/2022] Open
Abstract
Seedbanks are expected to buffer populations against disturbances, such as fire, that could alter the genetic composition of smaller, ephemeral adult populations. However, seedling genotypes may be influenced by the spatially heterogeneous nature of both the seedbank and the disturbance (for example, germination may vary with local disturbance) and also by selection acting on germination and post-germination performance. We used microsatellite-DNA surveys of seedlings emerging from the soil-stored seedbanks of Grevillea macleayana after wildfire to compare diversity and spatial structure in seedlings and adults, and through resampling of the seedling data set, to determine whether the resultant adult population reflected the effects of selection or random seedling mortality. The large post-fire seedling cohorts captured the full allelic diversity of the pre-fire adult population. However, we found a mismatch in the genotypic structure of adults and seedlings. Seedlings displayed larger heterozygous deficits than adults; however, over the ensuing 11 years, seedling heterozygosity eventually matched values for the pre-fire adults. Increasing heterozygosity among adults has generally been attributed to heterosis and/or reduction in Wahlund effects via self-thinning. Resampling of early post-fire seedlings to generate samples of equivalent size to survivors at 11 years showed that increases in heterozygosity must be driven by selection favouring outcrossed seed. This finding is important in an evolutionary context but also has implications for the restoration of natural or managed populations where a seedbank is a viable source of recruits.
Collapse
Affiliation(s)
- D G Roberts
- Institute for Conservation Biology and Environmental Management, School of Biological Sciences, University of Wollongong, Wollongong, NSW, Australia
| | - K M Ottewell
- 1] Institute for Conservation Biology and Environmental Management, School of Biological Sciences, University of Wollongong, Wollongong, NSW, Australia [2] Department of Parks and Wildlife, WA Conservation Science Centre, Bentley, WA, Australia
| | - R J Whelan
- Institute for Conservation Biology and Environmental Management, School of Biological Sciences, University of Wollongong, Wollongong, NSW, Australia
| | - D J Ayre
- Institute for Conservation Biology and Environmental Management, School of Biological Sciences, University of Wollongong, Wollongong, NSW, Australia
| |
Collapse
|
8
|
Mandák B, Zákravský P, Mahelka V, Plačková I. Can soil seed banks serve as genetic memory? A study of three species with contrasting life history strategies. PLoS One 2012. [PMID: 23185340 PMCID: PMC3504043 DOI: 10.1371/journal.pone.0049471] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
We attempted to confirm that seed banks can be viewed as an important genetic reservoir by testing the hypothesis that standing (aboveground) plants represent a nonrandom sample of the seed bank. We sampled multilocus allozyme genotypes from three species with different life history strategies: Amaranthus retroflexus, Carduus acanthoides, Pastinaca sativa. In four populations of each species we analysed the extent to which allele and genotype frequencies vary in consecutive life history stages including the summer seed bank, which has been overlooked up to now. We compared the winter seed bank (i.e., seeds collected before the spring germination peak), seedlings, rosettes, the summer seed bank (i.e., seeds collected after the spring germination peak) and fruiting plants. We found that: (1) All three species partitioned most of their genetic diversity within life history stages and less among stages within populations and among populations. (2) All genetic diversity parameters, except for allele frequencies, were similar among all life history stages across all populations in different species. (3) There were differences in allele frequencies among life history stages at all localities in Amaranthus retroflexus and at three localities in both Carduus acanthoides and Pastinaca sativa. (4) Allele frequencies did not differ between the winter and summer seed bank in most Carduus acanthoides and Pastinaca sativa populations, but there was a marked difference in Amaranthus retroflexus. In conclusion, we have shown that the summer seed bank is not genetically depleted by spring germination and that a majority of genetic diversity remains in the soil through summer. We suggest that seed banks in the species investigated play an important role by maintaining genetic diversity sufficient for recovery rather than by accumulating new genetic diversity at each locality.
Collapse
Affiliation(s)
- Bohumil Mandák
- Institute of Botany, Academy of Sciences of the Czech Republic, Průhonice, Czech Republic.
| | | | | | | |
Collapse
|
9
|
Falahati-Anbaran M, Lundemo S, Ågren J, Stenøien HK. Genetic consequences of seed banks in the perennial herb Arabidopsis lyrata subsp. petraea (Brassicaceae). AMERICAN JOURNAL OF BOTANY 2011; 98:1475-1485. [PMID: 21875972 DOI: 10.3732/ajb.1100021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
PREMISE OF THE STUDY Seed banks may increase the effective population size (N(e)) of plants as a result of elevated coalescence times for alleles residing in the populations. This has been empirically demonstrated in populations of the annual Arabidopsis thaliana, whereas comparable data for perennial species are currently lacking. We studied the contribution of seed banks to effective sizes of natural populations of the self-incompatible, perennial Arabidopsis lyrata subsp. petraea, a close relative of A. thaliana. • METHODS Fourteen populations of A. lyrata collected throughout the Norwegian distribution range were analyzed using microsatellite markers. • KEY RESULTS The genetic composition of seed-bank and aboveground cohorts was found to be highly similar, with little genetic differentiation between cohorts in most populations. However, the proportion of private alleles was higher in aboveground than in seed-bank cohorts. The presence of seed banks significantly increased total N(e), but the contribution from seed banks to overall N(e) were lower than the contribution from aboveground cohorts in most populations. Estimated historical N(e) values, reflecting the effective sizes of populations throughout the history of the species, were considerably higher than estimates of contemporary N(e), reflecting number of reproducing individuals within the past few generations. • CONCLUSIONS The results show that the seed bank contributes to total N(e) in the perennial herb A. lyrata. However, the contribution is similar to or lower than that of the above-ground fraction of the population and markedly weaker than that previously documented in the annual A. thaliana.
Collapse
Affiliation(s)
- Mohsen Falahati-Anbaran
- Department of Biology, Norwegian University of Science and Technology, N-7491 Trondheim, Norway.
| | | | | | | |
Collapse
|
10
|
Octavio-Aguilar P, González-Astorga J, Vovides AP. Genetic diversity through life history of Dioon edule Lindley (Zamiaceae, Cycadales). PLANT BIOLOGY (STUTTGART, GERMANY) 2009; 11:525-536. [PMID: 19538391 DOI: 10.1111/j.1438-8677.2008.00157.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The distribution of genetic diversity and structure for three populations of Dioon edule Lindley (Zamiaceae) at Monte Oscuro (MO), El Farallón (EF) and Rancho del Niño (RN) in Veracruz, Mexico was studied using 20 allozyme loci, considering four life history classes: seeds, seedlings, juveniles and adults. The MO population is genetically less diverse than the EF and RN populations. Total and local inbreeding differ significantly between life history classes. An increment of inbreeding among all classes was observed, and genetic differentiation among populations was higher in seeds and seedlings than in juveniles and adults. In terms of percentage of polymorphic loci, the MO seeds showed least (80%), followed by RN (95%) and EF had the highest values (100%), probably because of a reduction in effective population size and habitat fragmentation processes. In this context, the mean effective population size was 23.2 +/- 11.3 for all populations. We conclude that seed cohorts in EF and RN represent a reservoir of genetic diversity within these two populations. Also, preservation of adult plants is an essential aspect to consider in management and conservation efforts for populations of Dioon edule in natural conditions.
Collapse
Affiliation(s)
- P Octavio-Aguilar
- Laboratorio de Genética de Poblaciones, Departamento de Biología Evolutiva, Instituto de Ecología, Xalapa, Veracruz, México
| | | | | |
Collapse
|
11
|
Hock Z, Szövényi P, Schneller JJ, Tóth Z, Urmi E. Bryophyte diaspore bank: a genetic memory? Genetic structure and genetic diversity of surface populations and diaspore bank in the liverwort Mannia fragrans (Aytoniaceae). AMERICAN JOURNAL OF BOTANY 2008; 95:542-548. [PMID: 21632380 DOI: 10.3732/ajb.2007283] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Propagule banks are assumed to be able to store considerable genetic variability. Bryophyte populations are expected to rely more heavily on stored propagules than those of seed plants due to the vulnerability of the haploid gametophyte. This reliance has important implications for the genetic structure and evolutionary potential of surface populations. A liverwort, Mannia fragrans, was used to test whether the bryophyte diaspore bank functions as a "genetic memory." If a diaspore bank is capable of conserving genetic variability over generations, the levels of genetic diversity in the soil are expected to be similar or higher than at the surface. Surface and diaspore bank constituents of two populations of M. fragrans were investigated. Genetic structure and diversity measured as unbiased heterozygosity were analyzed using three ISSR markers. Similar genetic diversities were found in the soil (H(s) = 0.067) and at the surface (H(s)= 0.082). However, more haplotypes and specific haplotype lineages were present in soil samples. The results suggest that the bryophyte diaspore bank has an important role in accumulating genetic variability over generations and seasons. It is postulated that the role of the diaspore bank as a "genetic memory" is especially important in species of temporarily available habitats that have long-lived spores and genetically variable populations.
Collapse
Affiliation(s)
- Zsófia Hock
- Institute of Systematic Botany, University of Zürich, Zürich, 8008, Zollikerstrasse 107, Switzerl
| | | | | | | | | |
Collapse
|
12
|
Honnay O, Bossuyt B, Jacquemyn H, Shimono A, Uchiyama K. Can a seed bank maintain the genetic variation in the above ground plant population? OIKOS 2007. [DOI: 10.1111/j.2007.0030-1299.16188.x] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
13
|
Shimamura R, Kachi N, Kudoh H, Whigham DF. Hydrochory as a determinant of genetic distribution of seeds within Hibiscus moscheutos (Malvaceae) populations. AMERICAN JOURNAL OF BOTANY 2007; 94:1137-1145. [PMID: 21636481 DOI: 10.3732/ajb.94.7.1137] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Seed dispersal is a major determinant of the spatial genetic structure of plant populations. In this study, we evaluated the role of distinct hydrologic regimes in determining the spatial genetic structure of the seed bank of the wetland plant Hibiscus moscheutos. We analyzed seeds in surface soil samples collected in the autumn and the following spring by determining their allozyme genotypes and estimated the pattern in seed movements during flooding. We selected study sites in nontidal and tidal wetlands with different flooding regimes. One nontidal site had no flooding, while the second nontidal site was inundated for most of the year. One tidal wetland site flooded with almost every tide, and a second tidal site was inundated at moderate frequency. Genetic makeup of the seed bank at the nonflooded site changed little between seasons. Secondary seed dispersal altered absolute allele frequencies at the other three sites, with the greatest change occurring at the two tidally influenced sites. This study demonstrates that secondary hydrochory influences the genetic composition of the seed bank and that hydrologic conditions play an important role in determining the local patterns in seed movements.
Collapse
Affiliation(s)
- Ryouji Shimamura
- Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University, Minami-osawa 1-1, Hachioji 192-0397, Japan
| | | | | | | |
Collapse
|
14
|
Human disturbance reduces genetic diversity of an endangered tropical tree, Prunus africana (Rosaceae). CONSERV GENET 2007. [DOI: 10.1007/s10592-007-9343-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
15
|
Jones FA, Hubbell SP. Demographic spatial genetic structure of the Neotropical tree, Jacaranda copaia. Mol Ecol 2006; 15:3205-17. [PMID: 16968265 DOI: 10.1111/j.1365-294x.2006.03023.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We used genotypes from six microsatellite loci and demographic data from a large mapped forest plot to study changes in spatial genetic structure across demographic stages, from seed rain to seedlings, juveniles, and adult diameter classes in the Neotropical tree, Jacaranda copaia. In pairwise comparisons of genetic differentiation among demographic classes, only seedlings were significantly differentiated from the other diameter classes; F(ST) values ranged from 0.006 to 0.009. Furthermore, only seedlings showed homozygote excess suggesting biparental inbreeding in the large diameter reproductive adults. We found very low levels of relatedness in the first distance class of trees, 1-26 cm diameter (F(ij) = 0.011). However, there was a 5- to 10-fold rise in relatedness in the smallest distance class, from the smallest to the largest tree diameter classes (F(ij) = 0.110 for individuals > 56 cm diameter). A variety of non-mutually exclusive mechanisms have been invoked perviously to explain such a pattern, including natural selection, history, or nonequilibrium population dynamics. The long-term demographic data available for this species allow us to evaluate these mechanisms. Jacaranda is a fast-growing, light-demanding species with low recruitment rates and high mortality rates in the smaller diameter classes. It successfully regenerates only in large light gaps, which occur infrequently and stochastically in space and time. These factors contribute to the nonequilibrium population dynamics and observed low genetic structure in the small size classes. We conclude that the pattern of spatial genetic transitions in Jacaranda is consistent with overlapping related generations and strong but infrequent periods of high recruitment, followed by long periods of population decline.
Collapse
Affiliation(s)
- F A Jones
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Ancon, Balboa, Republic of Panama.
| | | |
Collapse
|
16
|
González-Martínez SC, Burczyk J, Nathan R, Nanos N, Gil L, Alía R. Effective gene dispersal and female reproductive success in Mediterranean maritime pine (Pinus pinaster Aiton). Mol Ecol 2006; 15:4577-88. [PMID: 17107484 DOI: 10.1111/j.1365-294x.2006.03118.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Understanding population-scale processes that affect allele frequency changes across generations is a long-standing interest in genetic, ecological and evolutionary research. In particular, individual differences in female reproductive success and the spatial scale of gene flow considerably affect evolutionary change and patterns of local selection. In this study, a recently developed maximum-likelihood (ML) method based on established offspring, the Seedling Neighbourhood Model, was applied and exponentially shaped dispersal kernels were fitted to both genetic and ecological data in a widespread Mediterranean pine, Pinus pinaster Aiton. The distribution of female reproductive success in P. pinaster was very skewed (about 10% of trees mothered 50% of offspring) and significant positive female selection gradients for diameter (gamma = 0.7293) and cone crop (gamma = 0.4524) were found. The selective advantage of offspring mothered by bigger trees could be due to better-quality seeds. These seeds may show more resilience to severe summer droughts and microsite variation related to water and nutrient availability. Both approaches, ecological and of parentage, consistently showed a long-distance dispersal component in saplings that was not found in dispersal kernels based on seed shadows, highlighting the importance of Janzen-Connell effects and microenvironmental variation for survival at early stages of establishment in this Mediterranean key forest tree.
Collapse
|
17
|
Mandák B, Bímová K, Mahelka V, Placková I. How much genetic variation is stored in the seed bank? A study of Atriplex tatarica (Chenopodiaceae). Mol Ecol 2006; 15:2653-63. [PMID: 16842434 DOI: 10.1111/j.1365-294x.2006.02953.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We investigated to what extent the soil seed bank differed genetically and spatially in comparison to three consecutive life history stages (seedlings, mature plants, and fruiting plants) in a natural population of Atriplex tatarica. Representatives of particular life history stages from twenty subunits within a large population were randomly collected and subjected to allozyme analysis. Comparison of population polymorphism among various life history stages showed significant differences in observed heterozygosity (H(O)) and F statistics (F(IS) and F(ST)), but nonsignificant ones in the cases of number of alleles per polymorphic locus (A) and gene diversity (H(S)). These results indicate an increasing number of heterozygotes, a decreasing level of inbreeding and an increase of the partitioning genetic diversity among populations with increasing population age. Spatial autocorrelation was used to calculate f, the average co-ancestry coefficient between individuals within distance intervals of two meters along a 39 m long transect. Significant positive fine scale genetic structure was detected in mature and fruiting plants but not in soil seeds and seedlings stages. The results of the presented study on A. tatarica indicated that significant differences exist in genetic differentiation, differentiation in allele frequencies and spatial autocorrelation among early (soil seeds and seedlings) and late (mature and fruiting plants) life history stages but not within early and late ones. This pattern suggests that, rather than storing genetic variability in the soil or germination and establishment success, self-thinning might be the major microselective force in populations of A. tatarica.
Collapse
Affiliation(s)
- B Mandák
- Institute of Botany, Academy of Sciences of the Czech Republic, CZ-252 43 Průhonice, Czech Republic.
| | | | | | | |
Collapse
|
18
|
Comparison of genetic variation in populations of wild rice, Oryza rufipogon, plants and their soil seed banks. CONSERV GENET 2006. [DOI: 10.1007/s10592-006-9132-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
19
|
Takeuchi Y, Ichikawa S, Konuma A, Tomaru N, Niiyama K, Lee SL, Muhammad N, Tsumura Y. Comparison of the fine-scale genetic structure of three dipterocarp species. Heredity (Edinb) 2004; 92:323-8. [PMID: 14735142 DOI: 10.1038/sj.hdy.6800411] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
We investigated the fine-scale genetic structure of three tropical-rainforest trees, Hopea dryobalanoides, Shorea parvifolia and S. acuminata (Dipterocarpaceae), in Peninsular Malaysia, all of which cooccurred within a 6-ha plot in Pasoh Forest Reserve. A significant genetic structure was found in H. dryobalanoides, weaker (but still significant) genetic structure in S. parvifolia and nonsignificant structure in S. acuminata. Seeds of all three species are wind dispersed, and their flowers are thought to be insect pollinated. The most obvious difference among these species is their height: S. parvifolia and S. acuminata are canopy species, whereas H. dryobalanoides is a subcanopy species. Clear differences were also found among these species in their range of seed dispersal, which depends on the height of the release point; so taller trees disperse their seed more extensively. The estimates of seed dispersal area were consistent with the degree of genetic structure found in the three species. Therefore, tree height probably had a strong influence on the fine-scale genetic structure of the three species.
Collapse
Affiliation(s)
- Y Takeuchi
- School of Agricultural Science, Nagoya University, Nagoya 464-8601, Japan
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Kelly BA, Hardy O, Bouvet JM. Temporal and spatial genetic structure in Vitellaria paradoxa (shea tree) in an agroforestry system in southern Mali. Mol Ecol 2004; 13:1231-40. [PMID: 15078458 DOI: 10.1111/j.1365-294x.2004.02144.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ten microsatellite loci were used to investigate the impact of human activity on the spatial and temporal genetic structure of Vitellaria paradoxa (Sapotaceae), a parkland tree species in agroforestry systems in southern Mali. Two stands (forest and fallow) and three cohorts (adults, juveniles and natural regeneration) in each stand were studied to: (i) compare their levels of genetic diversity (gene diversity, HE; allelic richness, Rs; and inbreeding, FIS); (ii) assess their genetic differentiation (FST); and (iii) compare their levels of spatial genetic structuring. Gene diversity parameters did not vary substantially among stands or cohorts, and tests for bottleneck events were nonsignificant. The inbreeding coefficients were not significantly different from zero in most cases (FIS = -0.025 in forest and 0.045 in fallow), suggesting that the species is probably outbreeding. There was a weak decrease in F(IS) with age, suggesting inbreeding depression. Differentiation of stands within each cohort was weak (FST = 0.026, 0.0005, 0.010 for adults, juveniles and regeneration, respectively), suggesting extensive gene flow. Cohorts within each stand were little differentiated (FST = -0.001 and 0.001 in forest and fallow, respectively). The spatial genetic structure was more pronounced in fallow than in forest where adults showed no spatial structuring. In conclusion, despite the huge influence of human activity on the life cycle of Vitellaria paradoxa growing in parkland systems, the impact on the pattern of genetic variation at microsatellite loci appears rather limited, possibly due to the buffering effect of extensive gene flow between unmanaged and managed populations.
Collapse
Affiliation(s)
- Bokary Allaye Kelly
- Institut d'Economie Rurale, Programme Ressources Forestières Centre Régional de la Recherche Agronomique de Sikasso, Sikasso, Mali
| | | | | |
Collapse
|
21
|
Vitalis R, Glémin S, Olivieri I. When Genes Go to Sleep: The Population Genetic Consequences of Seed Dormancy and Monocarpic Perenniality. Am Nat 2004; 163:295-311. [PMID: 14970929 DOI: 10.1086/381041] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2003] [Accepted: 08/20/2003] [Indexed: 11/03/2022]
Abstract
In many annual plant populations, seeds may be dormant for several seasons before they germinate. Here, we investigate the consequences of both conditional (dispersed seeds cannot enter a dormant stage) and unconditional seed dormancy on the amount and the distribution of neutral genetic diversity within and among populations. We present joint demographic and population genetics models for single and subdivided populations and derive the effective size and population differentiation at both local and metapopulation scales. We suggest that a Wahlund effect is unlikely to result from age structure alone. Furthermore, the differentiation among populations is decreased by the presence of seed banks. We also extend these models to describe monocarpic (semelparous) perennial life cycle, where the nonreproductive stages are vegetative rosettes instead of dormant seeds. The main difference between the models relies in the way the density-dependent regulation is acting. The effective size of monocarpic perennial species may be less than the census number of individuals, and among-population differentiation is always larger than in annual species. We discuss our results in the light of recent population genetics surveys of annual plants with seed banks.
Collapse
Affiliation(s)
- Renaud Vitalis
- Laboratoire Genetique et Environnement, C C 065, Institut des Sciences de l'Evolution de Montpellier, Universite Montpellier II, 34095 Montpellier Cedex 05, France.
| | | | | |
Collapse
|
22
|
GONZÁLEZ-ASTORGA JORGE, VOVIDES ANDREWP, FERRER MIRIAMM, IGLESIAS CARLOS. Population genetics of Dioon edule Lindl. (Zamiaceae, Cycadales): biogeographical and evolutionary implications. Biol J Linn Soc Lond 2003. [DOI: 10.1046/j.1095-8312.2003.00257.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
23
|
|
24
|
Ueno S, Tomaru N, Yoshimaru H, Manabe T, Yamamoto S. Size-class differences in genetic structure and individual distribution of Camellia japonica L. in a Japanese old-growth evergreen forest. Heredity (Edinb) 2002; 89:120-6. [PMID: 12136414 DOI: 10.1038/sj.hdy.6800111] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2001] [Accepted: 04/18/2002] [Indexed: 11/09/2022] Open
Abstract
Size-class differences in genetic structure and individual spatial distribution were investigated for Camellia japonica within a 1-ha plot in a Japanese old-growth evergreen forest using microsatellite markers. Three size-classes were considered containing plants that were: 30-32.5 cm tall, 103.8 cm-200 cm tall and those that had a diameter at breast height > or =5 cm, designated JV1, JV2, and ADL, respectively. Each size-class contained 174 individuals. Morisita's index of dispersion indicated clumping of individuals was present within all size-classes, with JV2 displaying the highest level. The clumped distribution of JV1 individuals may be a result of limited seed dispersal, while that of JV2 may be attributed to heterogenieties of favourable microsites, such as canopy gaps. There were no significant differences in allele frequencies among size-classes. There were, however, some differences in spatial genetic structure among them. Moran's I spatial autocorrelation analysis revealed clear spatial genetic structure in class JV1 probably due to limited seed dispersal. In class JV2, genetic structure was not observed. Overlapping seed shadows, probably in canopy gaps, may lead to blurred genetic structure in JV2.
Collapse
Affiliation(s)
- S Ueno
- Laboratory of Forest Ecology and Physiology, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan.
| | | | | | | | | |
Collapse
|
25
|
SCHNABEL A, NASON JD, HAMRICK JL. Understanding the population genetic structure ofGleditsia triacanthosL.: seed dispersal and variation in female reproductive success. Mol Ecol 2002. [DOI: 10.1046/j.1365-294x.1998.00397.x] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- A. SCHNABEL
- Department of Biological Sciences, Indiana University, South Bend, IN 46634 USA,,
| | - J. D. NASON
- Department of Biological Sciences, University of Iowa, Iowa City, IA 52242 USA,,
| | - J. L. HAMRICK
- Departments of Botany and Genetics, University of Georgia, Athens, GA 30602 USA
| |
Collapse
|
26
|
Godoy JA, Jordano P. Seed dispersal by animals: exact identification of source trees with endocarp DNA microsatellites. Mol Ecol 2001; 10:2275-83. [PMID: 11555269 DOI: 10.1046/j.0962-1083.2001.01342.x] [Citation(s) in RCA: 222] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A long-standing challenge in studies of seed dispersal by animal frugivores has been the characterization of the spatial relationships between dispersed seeds and the maternal plants, i.e. the seed shadow. The difficulties to track unambiguously the origin of frugivore-dispersed seeds in natural communities has been considered an unavoidable limitation of the research field and precluded a robust analysis of the direct consequences of zoochory. Here we report that the multilocus genotype at simple sequence repeat (SSR; microsatellite) loci of the woody endocarp, a tissue of maternal origin, provides an unequivocal genetic fingerprint of the source tree. By comparing the endocarp genotype against the complete set of genotypes of reproductive trees in the population, we could unambiguously identify the source tree for 82.1% of the seeds collected in seed traps and hypothesize that the remaining 17.9% of sampled seeds come from other populations. Identification of the source tree for Prunus mahaleb seeds dispersed by frugivores revealed a marked heterogeneity in the genetic composition of the seed rain in different microhabitats, with a range of 1-5 distinct maternal trees contributing seeds to a particular landscape patch. Within-population dispersal distances ranged between 0 and 316 m, with up to 62% of the seeds delivered within 15 m of the source trees. Long distance dispersal events, detected by the exclusion of all reproductive trees in the population, accounted for up to 17.9% of the seeds sampled. Our results indicate strong distance limitation of seed delivery combined with infrequent long-distance dispersal events, extreme heterogeneity in the landscape pattern of genetic makeup, and a marked mosaic of multiple parentage for the seeds delivered to a particular patch.
Collapse
Affiliation(s)
- J A Godoy
- Laboratorio de Ecología Molecular, Estación Biológica de Doñana, CSIC, Apdo. 1056, E-41080 Sevilla, Spain
| | | |
Collapse
|
27
|
Finkeldey R. Forschung zur Vielfalt, vielfältige Forschung: Ziele und Wege der Forstgenetik | Research on diversity, diverse research: objectives and approaches in forest genetics. ACTA ACUST UNITED AC 2001. [DOI: 10.3188/szf.2001.0162] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The genetic information about forest trees is not only of crucial importance for the yield of forestry production systems,but also for determining the evolutionary adaptive potential of tree populations. Thus, the stability of forest ecosystems depends on the sustainable management of forest genetic resources. In this context, tree breeding and conservation of forest genetic resources are mentioned as main applications of research in forest genetics. Genetic inventories are conducted in order to observe the spatial distribution of genetic information at gene marker loci. Such studies allow us to elucidate the evolutionary history of populations and, thus, to draw conclusions about their evolutionary adaptability. Results of a genetic inventory of oak (Quercus spp.) populations native to Switzerland are presented, and their significance for the characterization of genetic systems and adaptive potential is discussed. Future research into forest genetics should aim at improving our understanding of the relationship between variation at biochemical and molecular marker loci and adaptive processes in forest tree populations. The temporal dynamics of genetic structures of forest tree populations as a consequence of anthropogenic environmental change is another important topic of forest genetics in particular for the conservation of rare species.
Collapse
Affiliation(s)
- Reiner Finkeldey
- Institut für Forstgenetik und Forstpflanzenzüchtung, Universität Göttingen, Büsgenweg 2, D-37077 Göttingen
| |
Collapse
|
28
|
Kameyama Y, Isagi Y, Nakagoshi N. Patterns and levels of gene flow in Rhododendron metternichii var. hondoense revealed by microsatellite analysis. Mol Ecol 2001; 10:205-16. [PMID: 11251799 DOI: 10.1046/j.1365-294x.2001.01181.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Parentage analysis was conducted to elucidate the patterns and levels of gene flow in Rhododendron metternichii Sieb. et Zucc. var. hondoense Nakai in a 150 x 70 m quadrant in Hiroshima Prefecture, western Japan. The population of R. metternichii occurred as three subpopulations at the study site. Seventy seedlings were randomly collected from each of three 10 x 10 m plots (S1, S2, and S3) on the forest floor of each subpopulation (A1, A2, and A3). Almost all parents (93.8%) of the 70 seedlings were unambiguously identified by using 12 pairs of microsatellite markers. Within the quadrant, adult trees less than 5 m from the centre of the seedling bank (plots S1, S2, and S3) produced large numbers of seedlings. The effects of tree height and distance from the seedling bank on the relative fertilities of adult trees were highly variable among subpopulations because of the differences in population structure near the seedling bank: neither distance nor tree height had any significant effect in subpopulation A1; distance from the seedling bank had a significant effect in subpopulation A2; and tree height had a significant effect in subpopulation A3. Although gene flow within each subpopulation was highly restricted to less than 25 m and gene flow among the three subpopulations was extremely small (0-2%), long-distance gene flow from outside the quadrant reached 50%. This long-distance gene flow may be caused by a combination of topographical and vegetational heterogeneity, differences in flowering phenology, and genetic substructuring within subpopulations.
Collapse
Affiliation(s)
- Y Kameyama
- Graduate School for International Development and Cooperation, Hiroshima University, Higashi-Hiroshima 739-8529, Japan.
| | | | | |
Collapse
|
29
|
Spatial genetic structure of delphinium nuttallianum populations: inferences about gene flow. Heredity (Edinb) 1999; 83 (Pt 5):541-50. [PMID: 10620026 DOI: 10.1038/sj.hdy.6885920] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The spatial genetic structure of a plant population provides a potential record of past gene flow and mating. We used hierarchical F-statistics and spatial autocorrelation to characterize spatial genetic differentiation of allozymes in adult Delphinium nuttallianum plants within and among six natural populations separated from one another by up to 3 km. Previous direct estimates suggested that gene flow is highly localized, averaging << 10 m. Earlier studies of seed-set, pollen-tube growth and progeny fitness suggested that partial reproductive isolation exists between plants growing too close together (<3 m) and too far apart (>100 m). Thus we anticipated substantial genetic differentiation on scales of a few to hundreds of metres. However, we detected little differentiation among the six populations, among replicate study plots within populations, or among subsections of study plots, except at the smallest scale of cm to m. These results suggest that relatively rare long-distance pollen movement has gone undetected and that postpollination selection may further modify genetic structure during the life cycle. Lack of differentiation is not at odds with the observation of partial reproductive isolation, because some loci may respond to spatial variation in selection without this response being evident at marker loci.
Collapse
|
30
|
Martínez-Palacios A, Eguiarte LE, Furnier GR. Genetic diversity of the endangered endemic Agave victoriae-reginae (Agavaceae) in the Chihuahuan Desert. AMERICAN JOURNAL OF BOTANY 1999; 86:1093-1098. [PMID: 10449387 DOI: 10.2307/2656971] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Long-lived perennials are a species-rich, ecologically important component of the North American deserts, yet we know little about their genetic structure, information important for their conservation. Agave victoriae-reginae is an endemic of the Chihuahuan Desert of northern Mexico that is endangered by collection for the ornamental trade. We examined levels and patterns of variation at ten polymorphic allozyme loci in ten populations representing the range of the species. Levels of genetic variation (mean H(e)= 0.335) and differentiation (mean F(ST) = 0.236) were high. Phenetic clustering suggested the existence of at least three distinct groups of populations. If this pattern of variation is representative of other long-lived desert perennials, it may explain the species richness of this group and will pose a real challenge to gene conservation efforts.
Collapse
Affiliation(s)
- A Martínez-Palacios
- Jardín Botánico, Instituto de Biología, Universidad Nacional Autónoma de México, Apartado Postal 70-614, México, D.F., 04510, México; and
| | | | | |
Collapse
|
31
|
Aldrich PR, Hamrick JL, Chavarriaga P, Kochert G. Microsatellite analysis of demographic genetic structure in fragmented populations of the tropical tree Symphonia globulifera. Mol Ecol 1998; 7:933-44. [PMID: 9711860 DOI: 10.1046/j.1365-294x.1998.00396.x] [Citation(s) in RCA: 146] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We developed genetic markers for three microsatellite loci in the tropical tree Symphonia globulifera and used them to examine the demographic genetic consequences of forest fragmentation. High levels of genetic variation were revealed in samples of adults, saplings, and seedlings. The more-variable loci exhibited less stability in allelic composition across sites and stages. The number of alleles per hectare (ha) of forest was similar when continuous forest plots were compared to plots from fragmented forest for all three stages. This pattern also held for the number of unique multilocus adult and sapling genotypes, but the number of unique seedling genotypes per ha of fragmented forest greatly exceeded expectations based on continuous forest data, probably due to the concentration of seeds into remnant forest patches by foraging bats. Significant inbreeding and genetic differentiation were most often associated with the fragmented forest and the seedlings. Finally, principal component analysis reaffirmed that a bottleneck, acting in concert with pre-existing genetic structure in the adults, had led to enhanced and rapid divergence in the seedlings following deforestation, a result that is of central interest for landscape management.
Collapse
Affiliation(s)
- P R Aldrich
- Botany Department, University of Georgia, Athens 30605, USA.
| | | | | | | |
Collapse
|
32
|
Kaufman SR, Smouse PE, Alvarez-buylla ER. Pollen-mediated gene flow and differential male reproductive success in a tropical pioneer tree, Cecropia obtusifolia Bertol. (Moraceae): a paternity analysis. Heredity (Edinb) 1998. [DOI: 10.1046/j.1365-2540.1998.00377.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
33
|
Maki M, Yahara T. Spatial structure of genetic variation in a population of the endangered plant Cerastium fischerianum var. molle (Caryophyllaceae). Genes Genet Syst 1997. [DOI: 10.1266/ggs.72.239] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Affiliation(s)
- Masayuki Maki
- Department of Biology, Fukuoka University of Education
| | | |
Collapse
|