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Biotic Interactions (GloBI) · NCBI – National Center for Biotechnology Information. Alsophila firma. Open Interactive Map. Alsophila firma image. Click to Display. Brief summary. No one has contributed a brief summary to this page yet. Explore what EOL knows about Alsophila firma. Add a brief summary to this page. Alsophila firma (Baker) D.S. Conant is an accepted name. This name is the accepted name of a species in the genus Alsophila (family Cyatheaceae). The record.

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Eguiarte; Spatial genetic analyses reveal strong genetic structure in two populations of the outcrossing tree fern Alsophila firma CyatheaceaeBotanical Journal of the Linnean SocietyVolumeIssue 3, 1 MarchPages —, https: The development of spatial genetic structure SGS in seed plants has been linked to several biological attributes of species, such as breeding system and life form. However, little is known about SGS in ferns, which together with lycopods are unique among land plants in having two free-living life stages.

We combined spatial aggregation statistics and spatial genetic autocorrelation analyses using five plastid microsatellites and one nuclear gene to investigate SGS in two populations of the outcrossing tree fern Alsophila firma Cyatheaceae.

We assessed how the observed patterns compare with those estimated for other ferns and seed plants. SGS in ferns appears to be higher than in most seed plants analysed to date. Contrary to our expectations, an outcrossing breeding system, wind dispersal and an arborescent life form did not translate into weak or no SGS. In ferns, SGS is probably being affected by the life cycle with two free-living life stages. The reproductive biology of ferns appears to be more complex than previously thought.

This implies that SGS in ferns is affected by some factors that cannot be inferred from the study of flowering plants. Spatial genetic structure SGS in plant species can be defined as the non-random spatial distribution of genotypes within populations. Population genetics theory predicts that in sexual species with restricted dispersal, a patchy distribution of genotypes will quickly develop in populations Loiselle et al.

The localized dispersal of propagules has been considered one of the main processes generating SGS Heywood, ; Loiselle et al. Despite the crucial role of propagule dispersal, SGS in plants is highly dependent on other demographic and biological factors, such as the extent and frequency of asexual reproduction van Rossum et al.

The analysis of SGS, therefore, can reveal the existence of relevant underlying ecological processes, such as clonal propagation Dutetch et al. Such processes would not only affect the levels of SGS, but would also affect the spatial aggregation of individuals Kalisz et al. In particular, asexual propagation can effectively increase SGS at short distances Alberto et al.

However, this would depend on the spatial extent at which clonal growth occurs and the frequency of clone intermingling Charpentier, For plants with mixed sexual and asexual reproduction, incorporating both aspects of reproduction is essential to make a correct inference about patterns of gene dispersal and inbreeding within populations Dutetch et al.

Tropicos | Name – Alsophila firma (Baker) D.S. Conant

Although factors affecting Alsophil are well understood, most studies have almost exclusively focused on seed plants, especially angiosperms. In general, herbaceous and selfing species tend to have stronger SGS than arboreal and outcrossing species Dutetch et al. To fully understand these correlations, the presence of SGS should be investigated in other groups of plants with different biological attributes. Besides flowering plants, ferns are a group that comprises species with different life forms and breeding systems.

Ferns, together with lycopods, are unique among land plants in having a complex life cycle with two free-living life stages i.

In this life cycle, meiosis and fertilization occur in different plants and dispersal is mainly achieved through propagules spores that develop prior to fertilization. In many ffirma of ferns, the resulting haploid gametophyte produces both ifrma and male gametes simultaneously and thus, if self-fertilized gametophytic selfinggenerates a completely homozygous embryo.


To date, few studies of SGS have focused on ferns species, all of which are terrestrial and acaulescent [ Pteris multifida Poir. Based on the wind-dispersal aosophila spores, fern populations are expected to show weak to no SGS.

Other factors, such as life form and breeding system, are probably linked to SGS in ferns. In general, arborescent ferns should have more readily dispersed spores, and thus have weaker SGS than smaller, acaulescent species.

However, the breeding mechanisms e. Species with a high frequency of asexual reproduction, such as alsophilz apogamous C. Conant Cyatheaceae in Mexico using spatial autocorrelation statistics. This is a rare species alsophilw occurs mainly as a riparian species in montane cloud forests from Mexico to Panama and western Ecuador, with stems that can reach 15 m in height Gastony, Some populations of A.

Clonal growth has been documented in several species of tree ferns, including A.

However, the frequency of clonal growth in natural populations remains unexplored using genetic resources. Alsophial our knowledge, molecular markers for tree ferns are only available for plastid DNA sequences e. Thus, we developed primers for highly variable plastid microsatellites [plastid simple sequence repeats SSRs ] and for the nuclear gene gapCp Schuettpelz et al.

We combined spatial aggregation statistics and widely used spatial genetic autocorrelation analyses to address the existence of SGS in populations of A.

We assessed how the observed patterns in this tree fern compare with those of other ferns and seed plants. Alternatively, frequent clonal growth would result in a significant spatial clustering of individuals and populations should thus exhibit increased levels of inbreeding, low levels of genetic diversity and higher SGS. Sample sites were located in two cloud forest patches in central—eastern Mexico.

The first site Huatusco, Veracruz: AH is xlsophila on a private biological reserve comprising c. The second site Tlanchinol, Hidalgo: ATL is found in an unprotected cloud forest patch of c. In each population, all identifiable individual aslophila AH: The location of individual stems was carefully mapped using the distance m and compass bearings between individuals, thus obtaining the relative spatial coordinates of each individual.

As a result of the poor quality of leaf tissue for some samples, PCR amplification of all markers was successful only for 74 out of and 99 out of individuals from AH and ATL, respectively. Spatial distribution of individual stems within the two studied populations of the tree fern Alsophila firma AH: Map showing geographical location of the two populations in Mexico open circles and the distribution of cloud forest patches grey. Due to the lack of single nucleotide polymorphisms, we restricted our analyses to five mononucleotide microsatellites alsopphila SSRs located within these regions, which were subjected to direct cycle sequencing High Throughput Genomic Unit, University of Washington, Washington, DC, USA.

Independent rounds of amplification and sequencing using 20 randomly chosen individuals were performed to assess genotyping errors.

Initial amplification of the nuclear gapCp gene glyceraldehydephosphate deshydrogenase ; Schuettpelz et al. The resulting sequences were manually aligned to other known gapCp sequences of ferns Schuettpelz et al. Gray EUEU Only the medium copy could be successfully aligned.

Specific primers were designed to amplify an intron of this copy of gapCp Supporting Information Table S1.

Alsophila firma | CITES

For each individual stem, products from independent rounds of alsophilw were sequenced using forward and reverse primers separately. Single nucleotide polymorphisms were identified by direct chromatogram inspection with Consed Gordon et al. Independent rounds of amplification and sequencing using 20 randomly chosen polymorphic individuals were undertaken to check for genotyping errors. The O r function describes the expected number alzophila points stems at a distance r from an arbitrary point.

These analyses were carried out on the total number of individual stems AH: This ensured that the CSR simulations were directly comparable to the observed clustering. An edge correction was applied, where the firrma of points in an incomplete ring was divided by the proportion of the ring lying within the observation window Wiegand, The number of points within each ring was maximized by setting the ring width to 2 m, reducing the raggedness of the function.


Finally, we tested for the effects of reduced sample size by conducting the same analyses on a reduced dataset containing only those individual stems that were successfully genotyped 74 in AH and 99 in ATL. The nuclear SNP genotypes were used to alsophia gene alleles for each individual stem using the program Phase 2.

The program was set to run with alsophhila default parameters: Five independent runs were performed to check for consistency of results. Using the allele data for each individual i.

Cyatheaceae: The Scaly Tree Ferns

To identify individual stems produced by clonal reproduction, we estimated the probability that two individuals share the same genomic combination plastid SSR haplotype and nuclear alsopphila by sexual reproduction p gen. However, the presence of identical ramets in distinct spatial clusters might be the result of sexual reproduction. Following Alberto et al. For each population, autocorrelation analyses were performed separately on the plastid SSR haplotype and gapCp allele data sets by considering only individual pairs belonging to different clonal categories.

To estimate how clonal growth affects SGS, we performed autocorrelation analyses using all pairs of sampled individual stems. All analyses were performed using Loiselle et alsoohila. Kinship coefficients were computed for 20 distance intervals maximum distance in metres that alsiphila arbitrarily defined to maximize the number of pairwise comparisons. Significance of R L at each distance interval and the inbreeding coefficient F IS were obtained after 10 random permutations of individuals among locations and genes among individuals, respectively.

Significant SGS was evaluated by testing the regression slope of R L on the logarithm of distance b R with 10 replicates.

In both populations of A. In general, these analyses indicated that individuals from ATL form more restricted and dense clusters than individuals from AH.

The ATL population showed a higher O -ring statistic at the first distance interval and a more rapid decrease of clustering with increasing distance. The tests performed with the reduced datasets showed dirma the reduction in sample size in AH produced a less intensive clustering, but did not affect the spatial patterns of clustering data not shown. Spatial aggregation O -ring statistic of individuals in the two studied populations of the tree fern Alsophila firma AH: In plants with wind dispersion and random mating, the values of observed heterozygosity H O should approach those of gene diversity H S.

The two studied populations of A. Accordingly, inbreeding coefficients F IS were not significantly different from zero. Populations also exhibited a high genetic diversity for the five plastid SSRs, with similar measures of haplotype diversity, 0. There was no evidence of significant levels of homoplasy due to mutation in the five plastid SSRs.

Genetic diversity estimates for plastid haplotypes plastid SSRs and nuclear alleles gapCp and statistics of clonal extent in the two studied populations of the tree fern Alsophila firma AH: The genetic analyses showed that c. Accordingly, both populations showed substantial levels of clonal diversity R0.

Given the numbers of nuclear markers used, a low power to detect sexually produced identical genotypes is possible, especially in AH, where there is a single most common nuclear gapCp-M allele Supporting Information Table S2. This is probably related to differences in the size of clones i.

The proportion of clones occurring more than twice was greater in ATL than in AH, where the bigger clones comprised six and nine individual stems, respectively Supporting Information Fig. The analyses of SGS in the two populations of A. Permutation tests showed alophila regression slopes were significantly different from zero in all analyses Table 2.