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1.
Nine dinucleotide microsatellites were developed in Astronium urundeuva (Anacardiaceae), a typical tree of the seasonally‐dry tropical forests of South America and characterized on three populations from Paraguay and Argentina. Seven microsatellites were found polymorphic in within population gene diversities ranging from 0.32 to 0.91, and an observed number of alleles varying between four and 20. Despite their relatively low number of alleles, these markers proved valuable tools in detecting genetic structure between three populations in Paraguay and North Argentina.  相似文献   

2.
Dicorynia guianensis is a canopy tree endemic to French Guyana and the first to be exploited as timber wood. To investigate levels of diversity and dynamics of gene flow in a 40‐ha study plot, highly polymorphic microsatellite markers were developed. An enriched microsatellite library was constructed and seven microsatellite primer pairs were developed. Total genomic DNA was extracted and amplified from cambium tissue from 172 adult individuals. The level of genetic diversity was found to be low. A large heterozygote deficiency was found at one locus. This was resolved by redesigning the primer set.  相似文献   

3.
BACKGROUND [corrected] AND AIMS: The Caesalpinia hintonii group comprises six species of endemic shrubs or trees, C. epifanioi, C. hintonii, C. laxa, C. macvaughii, C. melanadenia and C. oyamae, found in scattered patches of seasonally dry forest in the Río Balsas depression and the neighbouring Tehuacán-Cuicatlán valley, which are part of the Mexican morphotectonic province of Sierra Madre del Sur. An evaluation is made of phylogeographic patterns and genetic diversity with a phylogenetic analysis of the C. hintonii complex in order to study the dynamics of speciation in this endemic group of legumes. METHODS: A phylogeographic study based on four highly variable non-coding plastid regions (trnL intron, trnL-F intergenic spacer, trnH-psbA intergenic spacer, and accD-psaI intergenic spacer) was carried out for the Caesalpinia hintonii complex. Five of the six taxa of the C. hintonii complex were included. KEY RESULTS AND CONCLUSIONS: The plastid analyses involving multiple accessions of each taxon from throughout their ranges resolved C. epifanioi and C. hintonii as well-supported clusters, but C. oyamae has two unexpectedly divergent lineages. Two well-supported geographic clades: eastern (C. epifanioi, C. melanadenia and C. oyamae) and western (C. hintonii and C. macvaughii) were established. The analyses performed provide evidence of recent morphostatic radiation in C. oyamae resulting from isolation and local adaptation. This pattern of genetic differentiation without morphological divergence may be a model that fits many groups of tropical woody taxa inhabiting similarly dry forests subjected to shifting selection.  相似文献   

4.
Microsatellite loci that were previously developed in the tropical tree Tabebuia aurea were used for the genetic analysis of Tabebuia roseo-alba populations. Nine of 10 simple sequence repeat markers were amplified, and the polymorphism was assessed in 58 individuals sampled from two stands in southeastern Brazil. All loci were polymorphic with Mendelian inheritance. The allele numbers were high, ranging from 5 to 13 in population I and 3 to 7 in population II, with means of 8.9 and 5.5, respectively. We conclude that these markers can be efficiently used for parentage and gene-flow studies.  相似文献   

5.
? Premise of the study: Microsatellite markers were developed for Dimorphandra mollis (Leguminosae), a widespread tree in the Brazilian cerrado (a savanna-like vegetation). ? Methods and Results: Microsatellite markers were developed from an enriched library. The analyses of polymorphism were based on 56 individuals from three populations. Nine microsatellite loci were polymorphic, with the number of alleles per locus ranging from three to 10 across populations. The observed and expected heterozygosities per locus and population ranged from 0.062 to 0.850 and from 0.062 to 0.832, respectively. ? Conclusions: These microsatellites provide an efficient tool for population genetics studies and will be used to assess the genetic diversity and spatial genetic structure of D. mollis.  相似文献   

6.
In temperate forests, juvenile trees anticipate leaf phenology compared to adults, thus avoiding shading and herbivory. This is also expected to occur in seasonal tropical forests due to intense herbivory and shading during the rainy season; however, the anticipation of leaf phenology by juveniles in seasonal tropical forests has yet to be demonstrated. Stem‐succulent species are expected to be prone to juvenile phenological anticipation because these species are able to use water stored in their stems for leaf flushing in the dry season. We investigated this hypothesis by comparing leaf phenology (bud break, leaf expansion) of juveniles and adults of two species with contrasting wood densities in the transition between dry and rainy seasons in a tropical dry woodland. We also investigated the level of light limitation that juveniles experience in the rainy season. Both species exhibited bud break during the dry season, but only expanded their leaves with the occurrence of the first rains. In general, the stem‐succulent species had a more precocious bud break; however, anticipation by juveniles occurred only in the species with more dense wood. Canopy openness was lower than in temperate deciduous forests, but the fact that the full expansion of leaves occurred only with rainfall indicates that bud break in anticipation of canopy closure contributes only to keeping leaf photosynthetic balance from going negative, and not to higher carbon gain. The importance of anticipated budding for escaping herbivory remains an alternative explanation in need of investigation.  相似文献   

7.

Aim

Seasonally dry tropical forest (SDTF) of the Caribbean Islands (primarily West Indies) is floristically distinct from Neotropical SDTF in Central and South America. We evaluate whether tree species composition was associated with climatic gradients or geographical distance. Turnover (dissimilarity) in species composition of different islands or among more distant sites would suggest communities structured by speciation and dispersal limitations. A nested pattern would be consistent with a steep resource gradient. Correlation of species composition with climatic variation would suggest communities structured by broad‐scale environmental filtering.

Location

The West Indies (The Bahamas, Cuba, Hispaniola, Jamaica, Puerto Rico, US Virgin Islands, Guadeloupe, Martinique, St. Lucia), Providencia (Colombia), south Florida (USA) and Florida Keys (USA).

Taxon

Seed plants—woody taxa (primarily trees).

Methods

We compiled 572 plots from 23 surveys conducted between 1969 and 2016. Hierarchical clustering of species in plots, and indicator species analysis for the resulting groups of sites, identified geographical patterns of turnover in species composition. Nonparametric analysis of variance, applied to principal components of bioclimatic variables, determined the degree of covariation in climate with location. Nestedness versus turnover in species composition was evaluated using beta diversity partitioning. Generalized dissimilarity modelling partitioned the effect of climate versus geographical distance on species composition.

Results

Despite a set of commonly occurring species, SDTF tree community composition was distinct among islands and was characterized by spatial turnover on climatic gradients that covaried with geographical gradients. Greater Antillean islands were characterized by endemic indicator species. Northern subtropical areas supported distinct, rather than nested, SDTF communities in spite of low levels of endemism.

Main conclusions

The SDTF species composition was correlated with climatic variation. SDTF on large Greater Antillean islands (Hispaniola, Jamaica and Cuba) was characterized by endemic species, consistent with their geological history and the biogeography of plant lineages. These results suggest that both environmental filtering and speciation shape Caribbean SDTF tree communities.  相似文献   

8.
Seasonally dry tropical forests (SDTF) are a widely distributed vegetation type in the tropics, characterized by seasonal rainfall with several months of drought when they are subject to fire. This study is one of the first attempts to quantify above- and belowground biomass (AGB and BGB) and above- and belowground carbon (AGC and BGC) pools to calculate their recovery after fire, using a chronosequence approach (six forests that ranged form 1 to 29 years after fire and mature forest). We quantified AGB and AGC pools of trees, lianas, palms, and seedlings, and BGB and BGC pools (Oi, Oe, Oa soil horizons, and fine roots). Total AGC ranged from 0.05 to nearly 72 Mg C ha−1, BGC from 21.6 to nearly 85 Mg C ha−1, and total ecosystem carbon from 21.7 to 153.5 Mg C ha−1; all these pools increased with forest age. Nearly 50% of the total ecosystem carbon was stored in the Oa horizon of mature forests, and up to 90% was stored in the Oa-horizon of early successional SDTF stands. The soils were shallow with a depth of <20 cm at the study site. To recover values similar to mature forests, BGC and BGB required <19 years with accumulation rates greater than 20 Mg C ha−1 yr−1, while AGB required 80 years with accumulation rates nearly 2.5 Mg C ha−1 yr−1. Total ecosystem biomass and carbon required 70 and 50 years, respectively, to recover values similar to mature forests. When belowground pools are not included in the calculation of total ecosystem biomass or carbon recovery, we estimated an overestimation of 10 and 30 years, respectively.  相似文献   

9.
Ligustrum ovalifolium is a semi-evergreen tree distributed in the western part of Japan and southern Korea. This species contains an insular endemic variety, L. ovalifolium var. pacificum; this variety occurs only on the Izu Islands located south of the Japanese mainland Honshu. We isolated 10 polymorphic microsatellite loci from the species, and characterized them for 21 individuals from a population of L. ovalifolium. The primers developed in this study yielded an average 12.2 alleles per locus and an average expected heterozygosity of 0.78. These markers will be powerful tools for studying the genetic differentiation within the species.  相似文献   

10.
11.
We assessed the lizard assemblage from a priority conservation Caatinga area from northeastern Brazil, through a pluriannual ecological approach, to expand the understanding on biodiversity patterns of Neotropical semiarid habitats. The studied area presented one of the richest lizard faunas among Caatinga sites, being composed primarily by species typical from open landscapes. The local species composition was more similar to assemblages from adjacent Caatinga ecoregions than to those from other areas within the same ecoregion. The inventoried lizard assemblage consisted of a few common species and a majority of low abundance ones, and its overall richness and abundance did not differ between rainy and dry months. Our findings demonstrated that the composition of lizard assemblages did not match with the current proposed Caatinga ecoregions, and revealed that the studied assemblage followed a lognormal species-abundance distribution, showing no significant seasonal fluctuation in richness and abundance.  相似文献   

12.
Chronic anthropogenic disturbances and climate change have been recognized as drivers of biological reorganization across human-modified tropical landscapes, also negatively affecting the reproductive output of some plant species. Here, we investigated to what extent these drivers affect the reproductive output of Cenostigma microphyllum, a disturbance-adapted tree species endemic to the Caatinga dry forest. The production of flowers/inflorescence, fruits and seeds was estimated for 105 plants (≥3 cm diameter at soil height) across 11 forest stands (20 × 50 m each), covering gradients of chronic disturbances (e.g. goat and livestock herbivory; wood extraction; and removal of non-timber forest products) and aridity at the Catimbau National Park. We documented that when the drivers were analysed in isolation, the fruit-set was positively associated with increased wood extraction, and the fruit-set and total number of seeds/plots were reduced under increasing aridity. We also verified a complex interaction between wood extraction and aridity emerged. In forest stands, the combination of high levels of aridity and wood extraction leads to a decrease in the fruit-set and total number of seeds/plots. Conversely, the fruit-set and total number of seeds/plots increased in stands exposed to lower aridity but high levels of wood extraction. Our results suggest that chronic disturbances and aridity affect plant fitness in a complex way including both negative and positive effects on attributes related to plant reproductive performance, which could result in both proliferation and population decline in the same landscape. Although C. microphyllum benefits from anthropogenic disturbances and is considered a disturbance-adapted species, it apparently does not benefit from increases in aridity, which is an expected future scenario for the Caatinga dry forest.  相似文献   

13.
14.
We describe 10 primers for amplification of microsatellite loci for the mangrove, Avicennia germinans. Eight loci were isolated from a DNA sample from the Pacific coast of Baja California, Mexico and two loci were isolated from a DNA sample from the Atlantic coast of Bermuda. Polymorphism was investigated in a population from the Mexican Pacific coast (n = 15) and in four samples scattered throughout the range of the species. Total number of alleles for the species ranged from two to 10. Observed heterozygosity in the Mexican Pacific coast population ranged from 0.27 to 0.60, with two loci having fixed alleles.  相似文献   

15.
Phytochemical investigation of flowers from Geoffroea spinosa via ultra-performance liquid chromatography coupled with diode array and quadrupole time-of-flight mass spectrometry (UPLC-DAD-TOF-MS/MS) resulted in the characterization of fourteen compounds: six flavonoids, three hydroxycinnamic acid derivatives, and five hydroxycinnamic acid amide derivatives. This is the first report on the identification of hydroxycinnamic acid amide derivatives from the genus Geoffroea. The chemotaxonomic significance of the identified compounds is discussed.  相似文献   

16.
Biogeographic patterns of avifaunas associated with seasonally dry tropical forests in Mesoamerica are poorly understood despite their high levels of species richness and endemism. Through the parsimony analysis of endemicity, we analyzed biogeographic relationships of 650 resident species of birds associated with seasonally dry tropical forests from Mexico to Panama, based on potential distributions obtained through ecological niche modeling. Results show two general avifaunal groups, east and west of the Isthmus of Tehuantepec. Patterns of biogeographic distribution and species richness also helped illuminate the importance of key areas for birds associated to this habitat in the region.

Los patrones biogeográficos de las avifaunas asociadas a los bosques tropicales estacionalmente secos en Mesoamérica están pobremente entendidos, a pesar de que estas áreas poseen una gran riqueza de especies y endemismo. Analizamos las relaciones biogeográficas con base en distribuciones potenciales, hechas a partir de modelos del nicho ecológico usando el análisis de parsimonia de endemismos, de 650 especies de aves residentes asociadas a los bosques tropicales estacionalmente secos desde México hasta Panamá. Los resultados muestran dos grupos generales de la avifauna, al este y oeste del Istmo de Tehuantepec. El contexto biogeográfico y la riqueza de especies resalta también la importancia de áreas clave para las aves asociadas a este tipo de hábitat en la región.  相似文献   

17.
Aims Seasonally tropical dry forests of the Yucatan Peninsula are typically found in sites with nutrient-poor soils because of the recent geological origin of the region. The landscape is dominated by extensive karstic plates that shape environments where vegetation regeneration through seed germination may be limited by the availability of suitable microsites. In this study, we documented the survival and growth of seedlings from three dominant tree species (Bursera simaruba, Piscidia piscipula and Lysiloma latisiliquum) in seasonally tropical dry forests in Yucatan. Specifically, we evaluated the effect of nutrient addition (N and P, separately and in combination) on seedling survival and growth across three sites with differing levels of precipitation.Methods We conducted a nutrient addition experiment, whereby we established 12 plots of dimensions 10×10 m (100 m 2) at each site, from which three plots were randomly selected to receive one of four treatments: N addition, P addition, N and P addition and no nutrient addition (controls). Prior to treatment application, in each plot, we planted 10 seedlings of each species in October 2010 and subsequently conducted surveys of plant growth and survival every 20 days from November 2010 to April 2011.Important findings Overall, nutrient addition increased seedling survival and the magnitude of this effect was similar among sites. We did not observe an additive effect of the N + P treatment on survival. Similarly, we observed a positive effect of nutrient addition on seedling growth, but this effect was contingent upon site; regarding survival, the effects of N and P on seedling growth were not additive. These results suggest that seedling recruitment and growth in the three dominant species of trees in Yucatan are limited by nutrient availability but that the magnitude of this effect, particularly on seedling growth, is specific for species and site.  相似文献   

18.
Microsatellite loci were isolated from a Mahonia aquifolium cultivar. We describe the variability of 10 loci in invasive European and native North American M. aquifolium and their transspecies amplification in native Mahonia repens and Mahonia pinnata from North America and one species of the related genus Berberis (Berberis vulgaris), native to Europe. The markers should be useful to reveal the genetic origin of invasive Mahonia populations and differences in the genetic make up between invasive and native populations.  相似文献   

19.
Bruguiera gymnorrhiza is an ecologically and somewhat economically important mangrove tree species. We isolated 10 polymorphic microsatellite loci from B. gymnorrhiza using a dual‐suppression polymerase chain reaction (PCR) technique. These loci provided microsatellite markers with polymorphism of two to five alleles per locus within 216 individuals from nine natural populations of B. gymnorrhiza on Iriomote Island, the Sakishima Islands, Japan. The expected and observed heterozygosities ranged from 0.220 to 0.720 and from 0.104 to 0.447, respectively.  相似文献   

20.
We present 25 polymorphic microsatellite loci for Intsia palembanica, a highly valued timber species in the Indo-Malayan region, Australia and western Pacific islands. Microsatellite loci were tested for polymorphism across a total of 76 individuals from three natural populations from Irian Jaya, Indonesia. The average number of alleles for these microsatellites was 12.1 per locus, ranging from four to 19. The observed heterozygosity within the natural populations ranged from 0.01 to 0.96. The markers will enable us to evaluate the spatial-temporal population genetic structure and gene flow dynamics among populations. They can also be used for tracking and tracing wood from legally logged concessions.  相似文献   

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