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1.
Lett Appl Microbiol ; 70(3): 143-150, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31785004

RESUMO

Basidiomata were found on dead stems of wild native Formosa palm (Arenga engleri) in Taiwan. The fungus was identified based on morphology and internal transcribed spacer sequence comparison as the oil palm pathogen Marasmius palmivorus. A pathogenicity test with cultivated mycelium of M. palmivorus positively produced disease symptoms and death of non-wounded Formosa palm tree seedlings under excessive moisture conditions. These results indicate that mycelial inoculum may be more important for pathogenesis than spore inoculum and that the fungus does not require wounds for entry into the plant. Host records in the literature are critically revised. The extended geographical and host distribution indicate a greater risk by M. palmivorus in palm plantations than hitherto anticipated. SIGNIFICANCE AND IMPACT OF THE STUDY: Certain palm species are susceptible to disease caused by Marasmius palmivorus, particularly in oil and coconut palm plantations in tropical countries. Hitherto, there is no published information on the morphology and pathogenicity of the species in Taiwan.


Assuntos
Arecaceae/microbiologia , Marasmius/patogenicidade , Doenças das Plantas/microbiologia , Arecaceae/classificação , Óleo de Palmeira , Plântula/microbiologia , Taiwan , Árvores
2.
Molecules ; 24(23)2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31766411

RESUMO

Interest in edible oil extraction processes is growing interest because the final nutritional quality of the extracted oil depends on the procedure used to obtain ir. In this context, a domestic cold oil press machine is a valuable tool that avoids the use of chemicals during oil extraction, in an environmentally friendly way. Although babassu (Attalea speciosa) oil is economically important in several Brazilian regions due to its nutritional and healthy features, few studies have been conducted on the chemical composition and stability of babassu oils extracted by cold pressing. Babassu oil's major constituents are saturated fatty acids (~86.42%), with the most prevalent fatty acids being lauric (~47.40%), myristic (15.64%), and oleic (~11.28%) acids, respectively, within the recommended range by Codex Alimentarius, presenting atherogenicity and thrombogenicity indexes favorable for human consumption. Peroxide value, Rancimat, and TGA/DSC results indicated that babassu oil is stable to oxidation. Also, macro- (Na, K, Ca, Mg, P) and micro-elements (Fe, Mn, Cr, Se, Al, and Zn) of babassu oil were determined, revealing levels below the tolerable upper intake level (ULs) for adults. These findings demonstrated that cold-press extraction using a domestic machine yielded a high-quality oil that kept oil chemical composition stable to oxidation with natural antioxidants.


Assuntos
Antioxidantes/análise , Arecaceae/química , Elementos , Ácidos Graxos/análise , Óleos Vegetais/análise , Óleos Vegetais/isolamento & purificação , Arecaceae/classificação , Manipulação de Alimentos , Humanos , Estresse Oxidativo , Óleos Vegetais/química , Sementes/química
3.
G3 (Bethesda) ; 9(8): 2377-2393, 2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31167834

RESUMO

We report the first whole genome sequence (WGS) assembly and annotation of a dwarf coconut variety, 'Catigan Green Dwarf' (CATD). The genome sequence was generated using the PacBio SMRT sequencing platform at 15X coverage of the expected genome size of 2.15 Gbp, which was corrected with assembled 50X Illumina paired-end MiSeq reads of the same genome. The draft genome was improved through Chicago sequencing to generate a scaffold assembly that results in a total genome size of 2.1 Gbp consisting of 7,998 scaffolds with N50 of 570,487 bp. The final assembly covers around 97.6% of the estimated genome size of coconut 'CATD' based on homozygous k-mer peak analysis. A total of 34,958 high-confidence gene models were predicted and functionally associated to various economically important traits, such as pest/disease resistance, drought tolerance, coconut oil biosynthesis, and putative transcription factors. The assembled genome was used to infer the evolutionary relationship within the palm family based on genomic variations and synteny of coding gene sequences. Data show that at least three (3) rounds of whole genome duplication occurred and are commonly shared by these members of the Arecaceae family. A total of 7,139 unique SSR markers were designed to be used as a resource in marker-based breeding. In addition, we discovered 58,503 variants in coconut by aligning the Hainan Tall (HAT) WGS reads to the non-repetitive regions of the assembled CATD genome. The gene markers and genome-wide SSR markers established here will facilitate the development of varieties with resilience to climate change, resistance to pests and diseases, and improved oil yield and quality.


Assuntos
Arecaceae/classificação , Arecaceae/genética , Cocos/classificação , Cocos/genética , Variação Genética , Genoma de Planta , Genômica , Arecaceae/metabolismo , Arecaceae/parasitologia , Cocos/metabolismo , Cocos/parasitologia , Biologia Computacional/métodos , Resistência à Doença/genética , Marcadores Genéticos , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Anotação de Sequência Molecular , Filogenia , Óleos Vegetais/metabolismo , Estresse Fisiológico
4.
Mol Phylogenet Evol ; 133: 67-81, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30594734

RESUMO

Tribe Euterpeae is an economically and ecologically important group of Neotropical palms (Arecaceae). Some species are hyperdominant in the Neotropics, and many constitute a good source of revenue. To reconstruct the biogeographical history and diversification of the Euterpeae, we inferred a robust dated molecular phylogenetic hypothesis including 82% of the species sequenced for five DNA regions (trnD-trnT, CISP4, WRKY6, RPB2, and PHYB). Ancestral range was estimated using all models available in BioGeoBEARS and Binary State Speciation and Extinction analysis was used to evaluate the association of biome and inflorescence type with diversification rates. All intergeneric relationships were resolved providing insight on the taxonomic controversy of Jessenia, Euterpe and Prestoea. Three widely distributed Neotropical species were non-monophyletic, inviting a revision of species circumscriptions. The Euterpeae started its diversification in the mid Eocene (40 Mya), with most species-level divergence events occurring in the last 10 million years. Four colonization events from Central to South America were inferred. Different diversification rates were associated with biomes. Lowland rainforest was inferred as the ancestral biome of Euterpeae, attesting to the importance of lowland adapted lineages on the assembly of the montane flora. The two-fold higher speciation rate for montane taxa (compared with lowland rainforest taxa) was contemporaneous to the Andean orogenic uplift. The specialized beetle pollination of Oenocarpus with its hippuriform (horsetail shape) inflorescence was not associated with diversification rates in Euterpeae.


Assuntos
Arecaceae/classificação , Arecaceae/genética , América Central , Ecossistema , Filogenia , Filogeografia , Floresta Úmida , América do Sul
5.
Ann Bot ; 123(4): 641-655, 2019 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-30395146

RESUMO

BACKGROUND AND AIMS: Identifying the processes that generate and maintain biodiversity requires understanding of how evolutionary processes interact with abiotic conditions to structure communities. Edaphic gradients are strongly associated with floristic patterns but, compared with climatic gradients, have received relatively little attention. We asked (1) How does the phylogenetic composition of palm communities vary along edaphic gradients within major habitat types? and (2) To what extent are phylogenetic patterns determined by (a) habitat specialists, (b) small versus large palms, and (c) hyperdiverse genera? METHODS: We paired data on palm community composition from 501 transects of 0.25 ha located in two main habitat types (non-inundated uplands and seasonally inundated floodplains) in western Amazonian rain forests with information on soil chemistry, climate, phylogeny and metrics of plant size. We focused on exchangeable base concentration (cmol+ kg-1) as a metric of soil fertility and a floristic index of inundation intensity. We used a null model approach to quantify the standard effect size of mean phylogenetic distance for each transect (a metric of phylogenetic community composition) and related this value to edaphic variables using generalized linear mixed models, including a term for spatial autocorrelation. KEY RESULTS: Overall, we recorded 112 008 individuals belonging to 110 species. Palm communities in non-inundated upland transects (but not floodplain transects) were more phylogenetically clustered in areas of low soil fertility, measured as exchangeable base concentration. In contrast, floodplain transects with more severe flood regimes (as inferred from floristic structure) tended to be phylogenetically clustered. Nearly half of the species recorded (44 %) were upland specialists while 18 % were floodplain specialists. In both habitat types, phylogenetic clustering was largely due to the co-occurrence of small-sized habitat specialists belonging to two hyperdiverse genera (Bactris and Geonoma). CONCLUSIONS: Edaphic conditions are associated with the phylogenetic community structure of palms across western Amazonia, and different factors (specifically, soil fertility and inundation intensity) appear to underlie diversity patterns in non-inundated upland versus floodplain habitats. By linking edaphic gradients with palm community phylogenetic structure, our study reinforces the need to integrate edaphic conditions in eco-evolutionary studies in order to better understand the processes that generate and maintain tropical forest diversity. Our results suggest a role for edaphic niche conservatism in the evolution and distribution of Amazonian palms, a finding with potential relevance for other clades.


Assuntos
Arecaceae , Biodiversidade , Inundações , Floresta Úmida , Solo/química , Arecaceae/classificação , Bolívia , Brasil , Colômbia , Equador , Peru , Filogenia
6.
Mol Ecol Resour ; 19(1): 221-234, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30240120

RESUMO

Understanding the genetics of biological diversification across micro- and macro-evolutionary time scales is a vibrant field of research for molecular ecologists as rapid advances in sequencing technologies promise to overcome former limitations. In palms, an emblematic, economically and ecologically important plant family with high diversity in the tropics, studies of diversification at the population and species levels are still hampered by a lack of genomic markers suitable for the genotyping of large numbers of recently diverged taxa. To fill this gap, we used a whole genome sequencing approach to develop target sequencing for molecular markers in 4,184 genome regions, including 4,051 genes and 133 non-genic putatively neutral regions. These markers were chosen to cover a wide range of evolutionary rates allowing future studies at the family, genus, species and population levels. Special emphasis was given to the avoidance of copy number variation during marker selection. In addition, a set of 149 well-known sequence regions previously used as phylogenetic markers by the palm biological research community were included in the target regions, to open the possibility to combine and jointly analyse already available data sets with genomic data to be produced with this new toolkit. The bait set was effective for species belonging to all three palm sub-families tested (Arecoideae, Ceroxyloideae and Coryphoideae), with high mapping rates, specificity and efficiency. The number of high-quality single nucleotide polymorphisms (SNPs) detected at both the sub-family and population levels facilitates efficient analyses of genomic diversity across micro- and macro-evolutionary time scales.


Assuntos
Arecaceae/classificação , Arecaceae/genética , Marcadores Genéticos , Variação Genética , Genética Populacional/métodos , Técnicas de Genotipagem/métodos , Biologia Computacional , Evolução Molecular , Genoma de Planta , Genótipo , Biologia Molecular/métodos , Sequenciamento Completo do Genoma
7.
An Acad Bras Cienc ; 90(4): 3615-3624, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30184010

RESUMO

The jelly palm plant [Butia capitata (Martius) Beccari] is a native palm of the Cerrado biome used for many purposes in northern Minas Gerais State, Brazil. Dormancy is common in palm seeds, resulting in slow and uneven germination that may take years to complete. Modification in the growth pattern, anatomical parameters, physiological and biochemical characteristics of the plant can be verified due to changes in the light spectrum transmitted through colored shade nets used. Therefore, the objective of this study is to evaluate the effect of colored shade nets on the leaf and root anatomy of the jelly palm plant. The experiment was performed in a completely randomized design, with five treatments, ten replicates and eight plants per replicate, totaling 400 plants. Four colored photo-converter nets with 50% shading and different radiation proportions were employed: white (985 µmol.m-2.s-1), red (327 µmol.m-2.s-1), black (433 µmol.m-2.s-1) and silver (405 µmol.m-2.s-1). The plants cultivated under direct sunlight (1000 µmol.m-2.s-1) were considered as the control group. Leaf and root anatomical analysis was performed on 10 plants per treatment. It is possible to conclude that the colored shade nets caused changes in leaf and root anatomy of the jelly palm plant (Butia capitata).


Assuntos
Arecaceae/anatomia & histologia , Cor , Folhas de Planta/crescimento & desenvolvimento , Luz Solar , Arecaceae/classificação , Arecaceae/crescimento & desenvolvimento , Arecaceae/efeitos da radiação , Brasil , Fotossíntese/efeitos da radiação , Folhas de Planta/anatomia & histologia , Folhas de Planta/efeitos da radiação
8.
Heredity (Edinb) ; 121(2): 183-195, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29588509

RESUMO

Evolutionary success, as demonstrated by high abundance and a wide geographical range, is related to genetic variation and historical demography. Here we assess how climatic change during the Quaternary influenced the demography and distribution of the Neotropical swamp palm Mauritia flexuosa. Using microsatellite loci and coalescent analyses we examined how demographical dynamics affected genetic diversity, effective population size and connectivity through time and space. Mauritia flexuosa presents significant genetic differentiation between the Amazonian and Cerrado biomes and among different river basins. Amazonian lineages are ancient compared to lineages from the Cerrado, a pattern corroborated using the fossil pollen record, where the species was absent from the Cerrado during the cold and dry periods of the last glacial cycles, then returned during the wet, interglacial phases. Coalescent simulations show that the pattern of observed genetic diversity for M. flexuosa is most likely due to a range retraction during the Last Glacial Maximum, leading to multiple refugia and resulting in high differentiation between Amazonian and Cerrado biomes. Isolation-by-distance and by-environment also shaped the distribution and evolutionary success of M. flexuosa. Our study provides new insights into the historical factors that affected geographical distribution and structure genetic diversity, contributing to long-term evolutionary success.


Assuntos
Arecaceae/genética , Evolução Biológica , Demografia , Variação Genética , Genética Populacional , Árvores/genética , Arecaceae/classificação , Simulação por Computador , Haplótipos , Repetições de Microssatélites
9.
Genet Mol Res ; 16(3)2017 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-28873204

RESUMO

We assessed the level and distribution of genetic diversity in three species of the economically important palm genus Astrocaryum located in Pará State, in northern Brazil. Samples were collected in three municipalities for Astrocaryum aculeatum: Belterra, Santarém, and Terra Santa; and in two municipalities for both A. murumuru: Belém and Santo Antônio do Tauá and A. paramaca: Belém and Ananindeua. Eight microsatellite loci amplified well and were used for genetic analysis. The mean number of alleles per locus for A. aculeatum, A. murumuru, and A. paramaca were 2.33, 2.38, and 2.06, respectively. Genetic diversity was similar for the three species, ranging from HE = 0.222 in A. aculeatum to HE = 0.254 in A. murumuru. Both FST and AMOVA showed that most of the genetic variation was found within populations for all three species, but high genetic differentiation among populations was found for A. aculeatum. Three loci were not in Hardy-Weinberg equilibrium, with populations of A. paramaca showing a tendency for the excess of heterozygotes (FIS = -0.144). Gene flow was high for populations of A. paramaca (Nm = 19.35). Our results suggest that the genetic diversity within populations followed the genetic differentiation among populations due to high gene flow among the population. Greater geographic distances among the three collection sites for A. aculeatum likely hampered gene flow for this species.


Assuntos
Arecaceae/genética , Frequência do Gene , Desequilíbrio de Ligação , Polimorfismo Genético , Arecaceae/classificação , Evolução Molecular , Fluxo Gênico , Heterozigoto , Repetições de Microssatélites
10.
J Agric Food Chem ; 65(34): 7476-7482, 2017 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-28756671

RESUMO

Palm oil is one of the richest sources of tocotrienols and may contain other non-tocopherol vitamin E congeners. The vitamin E profiles of fully ripened fruit mesocarp of three Elaeis guineensis, two Elaeis oleifera, and one hybrid O × G palm fruit genotypes from Costa Rica were analyzed by high-performance liquid chromatography with fluorescence detection and gas chromatography-mass spectrometry after mechanical extraction by a screw press and chemical extraction with hexane. γ-Tocotrienol, α-tocotrienol, and α-tocopherol were the most abundant tocochromanols, while other tocopherols (ß-tocopherol, γ-tocopherol, and δ-tocopherol) and α-tocomonoenol were detected at minor concentrations. Significant differences in vitamin E profiles between genotypes were observed, and the variety E. oleifera Quepos (CB9204) had by far the highest content of total tocotrienols (890 µg/g of oil) and total vitamin E (892 µg/g of oil). Chemical extraction with hexane afforded up to 2.5-fold higher vitamin E yields than screw press extraction. α-Tocomonoenol co-eluted with γ-tocopherol in reversed-phase high-performance liquid chromatography analyses and is a possible source of error in the quantification of γ-tocopherol in foods.


Assuntos
Arecaceae/química , Frutas/química , Óleos Vegetais/química , Tocoferóis/química , Tocotrienóis/química , Arecaceae/classificação , Cromatografia Líquida de Alta Pressão , Costa Rica , Frutas/classificação , Cromatografia Gasosa-Espectrometria de Massas , Óleo de Palmeira , Óleos Vegetais/isolamento & purificação , Tocoferóis/isolamento & purificação , Tocotrienóis/isolamento & purificação
11.
Genet Mol Res ; 16(2)2017 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-28671259

RESUMO

The licuri palm Syagrus coronata plays a key role in the ecology and economy of Brazilian semiarid region. Nonetheless, genetic data about populations of this species are absent even though the intensive and uncontrolled exploitation since colonial periods has threatened the sustainability and viability of licuri populations. Therefore, we attempted to test the efficacy of transferability of microsatellite loci isolated from three palm tree species to S. coronata to analyze the population of this species throughout their range. A set of 19 heterologous microsatellite loci was tested in three native populations of S. coronata from the State of Bahia, northeastern Brazil, which amplified using distinct annealing temperatures (50°-60°C). Based on the 10 most polymorphic loci, the selected populations exhibited a mean number of alleles per locus of 9.8, and high genetic diversity values since the expected heterozygosity ranged from 0.573 to 0.754, while the observed heterozygosity varied from 0.785 to 1.000. In conclusion, the tested loci are transferrable and highly efficient to population studies in S. coronata, thus minimizing the lack of species-specific loci to the genetic monitoring of licuri populations.


Assuntos
Arecaceae/genética , Primers do DNA/normas , Repetições de Microssatélites , Arecaceae/classificação , Espécies em Perigo de Extinção , Marcadores Genéticos , Heterozigoto , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/normas , Polimorfismo Genético
12.
J Agric Food Chem ; 65(18): 3617-3626, 2017 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-28434221

RESUMO

Morphological traits, total lipid contents, and fatty acid profiles were assessed in fruits of several accessions of Elaeis oleifera [Kunth] Cortés, Elaeis guineensis Jacq., and their interspecific hybrids. The latter featured the highest mesocarp-to-fruit ratios (77.9-78.2%). The total lipid contents of both E. guineensis mesocarp and kernel were significantly higher than for E. oleifera accessions. Main fatty acids comprised C16:0, C18:1n9, and C18:2n6 in mesocarp and C12:0, C14:0, and C18:1n9 in kernels. E. oleifera samples were characterized by higher proportions of unsaturated long-chain fatty acids. Saturated medium-chain fatty acids supported the clustering of E. guineensis kernels in multivariate statistics. Hybrid mesocarp lipids had an intermediate fatty acid composition, whereas their kernel lipids resembled those of E. oleifera genotypes. Principal component analysis based on lipid contents and proportions of individual fatty acids permitted clear-cut distinction of E. oleifera, E. guineensis, and their hybrids.


Assuntos
Arecaceae/química , Frutas/química , Extratos Vegetais/química , Arecaceae/classificação , Arecaceae/genética , Arecaceae/metabolismo , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Frutas/classificação , Frutas/genética , Frutas/metabolismo , Estrutura Molecular , Extratos Vegetais/metabolismo
13.
Sci Rep ; 7: 43402, 2017 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-28262720

RESUMO

Angiosperm mitochondrial genomes (mtDNA) exhibit variable quantities of alien sequences. Many of these sequences are acquired by intracellular gene transfer (IGT) from the plastid. In addition, frequent events of horizontal gene transfer (HGT) between mitochondria of different species also contribute to their expanded genomes. In contrast, alien sequences are rarely found in plastid genomes. Most of the plant-to-plant HGT events involve mitochondrion-to-mitochondrion transfers. Occasionally, foreign sequences in mtDNAs are plastid-derived (MTPT), raising questions about their origin, frequency, and mechanism of transfer. The rising number of complete mtDNAs allowed us to address these questions. We identified 15 new foreign MTPTs, increasing significantly the number of those previously reported. One out of five of the angiosperm species analyzed contained at least one foreign MTPT, suggesting a remarkable frequency of HGT among plants. By analyzing the flanking regions of the foreign MTPTs, we found strong evidence for mt-to-mt transfers in 65% of the cases. We hypothesize that plastid sequences were initially acquired by the native mtDNA via IGT and then transferred to a distantly-related plant via mitochondrial HGT, rather than directly from a foreign plastid to the mitochondrial genome. Finally, we describe three novel putative cases of mitochondrial-derived sequences among angiosperm plastomes.


Assuntos
Transferência Genética Horizontal , Genoma Mitocondrial , Genomas de Plastídeos , Magnoliopsida/genética , Mitocôndrias/genética , Plastídeos/genética , Arecaceae/classificação , Arecaceae/genética , Sequência de Bases , DNA Mitocondrial , Evolução Molecular , Fagaceae/classificação , Fagaceae/genética , Lamiaceae/classificação , Lamiaceae/genética , Magnoliopsida/classificação , Filogenia , Rosaceae/classificação , Rosaceae/genética
14.
Syst Biol ; 66(2): 152-166, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-27616324

RESUMO

Rapidly growing biological data-including molecular sequences and fossils-hold an unprecedented potential to reveal how evolutionary processes generate and maintain biodiversity. However, researchers often have to develop their own idiosyncratic workflows to integrate and analyze these data for reconstructing time-calibrated phylogenies. In addition, divergence times estimated under different methods and assumptions, and based on data of various quality and reliability, should not be combined without proper correction. Here we introduce a modular framework termed SUPERSMART (Self-Updating Platform for Estimating Rates of Speciation and Migration, Ages, and Relationships of Taxa), and provide a proof of concept for dealing with the moving targets of evolutionary and biogeographical research. This framework assembles comprehensive data sets of molecular and fossil data for any taxa and infers dated phylogenies using robust species tree methods, also allowing for the inclusion of genomic data produced through next-generation sequencing techniques. We exemplify the application of our method by presenting phylogenetic and dating analyses for the mammal order Primates and for the plant family Arecaceae (palms). We believe that this framework will provide a valuable tool for a wide range of hypothesis-driven research questions in systematics, biogeography, and evolution. SUPERSMART will also accelerate the inference of a "Dated Tree of Life" where all node ages are directly comparable. [Bayesian phylogenetics; data mining; divide-and-conquer methods; GenBank; multilocus multispecies coalescent; next-generation sequencing; palms; primates; tree calibration.].


Assuntos
Classificação/métodos , Fósseis , Filogenia , Fatores Etários , Migração Animal , Animais , Arecaceae/classificação , Teorema de Bayes , Primatas/classificação , Reprodutibilidade dos Testes , Tempo
15.
Mol Phylogenet Evol ; 105: 126-138, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27521478

RESUMO

The tropical rain forests of Central Africa contain high levels of species diversity. Paleovegetation or biodiversity patterns suggested successive contraction/expansion phases on this rain forest cover during the last glacial maximum (LGM). Consequently, the hypothesis of the existence of refugia e.g. habitat stability that harbored populations during adverse climatic periods has been proposed. Understory species are tightly associated to forest cover and consequently are ideal markers of forest dynamics. Here, we used two central African rain forest understory species of the palm genus, Podococcus, to assess the role of past climate variation on their distribution and genetic diversity. Species distribution modeling in the present and at the LGM was used to estimate areas of climatic stability. Genetic diversity and phylogeography were estimated by sequencing near complete plastomes for over 120 individuals. Areas of climatic stability were mainly located in mountainous areas like the Monts de Cristal and Monts Doudou in Gabon, but also lowland coastal forests in southeast Cameroon and northeast Gabon. Genetic diversity analyses shows a clear North-South structure of genetic diversity within one species. This divide was estimated to have originated some 500,000years ago. We show that, in Central Africa, high and unique genetic diversity is strongly correlated with inferred areas of climatic stability since the LGM. Our results further highlight the importance of coastal lowland rain forests in Central Africa as harboring not only high species diversity but also important high levels of unique genetic diversity. In the context of strong human pressure on coastal land use and destruction, such unique diversity hotspots need to be considered in future conservation planning.


Assuntos
Arecaceae/classificação , Arecaceae/genética , Variação Genética , Filogeografia , Floresta Úmida , África Central , Genoma de Planta , Haplótipos , Tamanho da Amostra , Análise de Sequência de DNA , Fatores de Tempo
16.
Mol Phylogenet Evol ; 100: 57-69, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27060018

RESUMO

Several attempts have been made to generate complete species-level phylogenies for large clades, enabling comprehensive analyses of ecological or evolutionary hypotheses at the species level. No such phylogeny has, however, been generated for any major plant group yet, but here we generate such a phylogeny for the palm family (Arecaceae). We do this using a novel Bayesian approach, estimating the validity of intra-generic taxonomic groupings as topological constraints to assist in placing species without genetic or morphological data. From these we implement those that are supported by genetic or morphological data for a given genus or for related genera. The intergeneric relationships in our new phylogeny are surprisingly different from earlier phylogenies in the placement of genera within tribes, but largely identical to previous findings in the deeper branches in the phylogeny, pointing to the need for incorporating phylogenetic uncertainty in analyses based on this phylogeny. Initial analyses of the new phylogeny suggest non-constancy in diversification rates over time within genera, with an apparent increase in diversification rate over time, but no evidence for any geographic variation in the magnitude of this increase. We hope that our study will stimulate further evolutionary or ecological studies using palms as study organisms as well as discussions of the optimal way to place the many species without genetic or morphological data.


Assuntos
Arecaceae/classificação , Teorema de Bayes , Biodiversidade , Geografia , Filogenia , Especificidade da Espécie
17.
Mol Phylogenet Evol ; 97: 32-42, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26748268

RESUMO

Palms (Arecaceae) include economically important species such as coconut, date palm, and oil palm. Resolution of the palm phylogeny has been problematic due to rapid diversification and slow rates of molecular evolution. The focus of this study is on relationships of the 14 tribes of subfamily Arecoideae and their inferred ancestral areas. A targeted sequencing approach was used to generate a data set of 168 single/low copy nuclear genes for 34 species representing the Arecoideae tribes and the other palm subfamilies. Species trees from the concatenated and coalescent based analyses recovered largely congruent topologies. Three major tribal clades were recovered: the POS clade (Podococceae, Oranieae, Sclerospermeae), the RRC clade (Roystoneeae, Reinhardtieae, Cocoseae), and the core arecoid clade (Areceae, Euterpeae, Geonomateae, Leopoldinieae, Manicarieae, Pelagodoxeae). Leopoldinieae was sister to the rest of the core arecoids (Geonomateae, Manicarieae+Pelagodoxeae, and Areceae+Euterpeae). The nuclear phylogeny supported a North American origin for subfamily Arecoideae, with most tribal progenitors diversifying within the Americas. The POS clade may have dispersed from the Americas into Africa, with tribe Oranieae subsequently spreading into the Indo-Pacific. Two independent dispersals into the Indo-Pacific were inferred for two tribes within the core arecoids (tribes Areceae and Pelagodoxeae).


Assuntos
Arecaceae/classificação , Arecaceae/genética , Filogenia , África , Núcleo Celular/genética , Evolução Molecular , Oceano Índico , América do Norte , Oceano Pacífico , Filogeografia
18.
Rev Biol Trop ; 64(1): 5-15, 2016 03.
Artigo em Espanhol | MEDLINE | ID: mdl-28861988

RESUMO

Mammals and palms are important elements of fauna and flora in the Neotropics, and their interactions, such as fruit consumption and seed dispersal, are one of the most important ecological relationships in these ecosystems. The main objective of this study was to identify the relative importance of mammals in the dispersal and predation of Mauritia flexuosa palm fruits. We installed camera-traps in front of palm fallen seeds and clusters with fruits. A catalog of species was prepared with the recorded videos and the foraging behaviors exhibited were classified and identified. In addition, two exclusion treatments with three repetitions each were used. In the semi-open treatment, a plot was fenced with metal mesh leaving four open- ings in order to allow access only to small and medium sized mammals, while in the open treatment, the small, medium and large sized mammals had free access. In both cases, seed removal was evaluated. We recorded a total of 19 species of mammals, nine of which fed on palm fruits and the other five were seed dispersers. We reported for the first time the consumption of Mauritia flexuosa fruits by Atelocynus microtis. The species with the highest relative importance was Dasyprocta fuliginosa, which showed the highest percentage of seed dispersal (63.5%) compared to the other species. Tayassu peccary was identified as an in situ consumer, eating 45.3% of seeds without dispersing them. The number of seeds consumed in situ in the open treatment showed significant differences regarding the semi-open treatment, suggesting greater involvement of large mammals in this process. In conclusion, the fruits of M. flexuosa are an important food source for the local mammal com- munity. Additionally, the consumption of seeds under the canopy of the mother palm is proportionally greater than their dispersion. Generally, the pressure of frugivorous species over seeds may determine the reproductive strategies of plants. However, research on effective dispersion, dispersal distances and demographic impact should be conducted to determine the specific role of medium and large sized mammals in the ecology of this palm.


Assuntos
Arecaceae/crescimento & desenvolvimento , Comportamento Animal/fisiologia , Comportamento Alimentar/fisiologia , Mamíferos/fisiologia , Dispersão de Sementes/fisiologia , Animais , Arecaceae/classificação , Colômbia , Mamíferos/classificação
19.
Genet Mol Res ; 14(4): 16247-54, 2015 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-26662418

RESUMO

Genetic diversity and patterns of population structure of the 94 oil palm lines were investigated using species-specific simple sequence repeat (SSR) markers. We designed primers for 63 SSR loci based on their flanking sequences and conducted amplification in 94 oil palm DNA samples. The amplification result showed that a relatively high level of genetic diversity was observed between oil palm individuals according a set of 21 polymorphic microsatellite loci. The observed heterozygosity (Ho) was 0.3683 and 0.4035, with an average of 0.3859. The Ho value was a reliable determinant of the discriminatory power of the SSR primer combinations. The principal component analysis and unweighted pair-group method with arithmetic averaging cluster analysis showed the 94 oil palm lines were grouped into one cluster. These results demonstrated that the oil palm in Hainan Province of China and the germplasm introduced from Malaysia may be from the same source. The SSR protocol was effective and reliable for assessing the genetic diversity of oil palm. Knowledge of the genetic diversity and population structure will be crucial for establishing appropriate management stocks for this species.


Assuntos
Arecaceae/genética , Variação Genética , Genética Populacional , Repetições de Microssatélites , Alelos , Arecaceae/classificação , China , Evolução Molecular , Malásia , Filogenia , Polimorfismo Genético
20.
Cytogenet Genome Res ; 147(1): 70-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26594788

RESUMO

The endemic, highly polyploid, monotypic Madagascan palm genus Voanioala (2n ≈ 606) was studied with regard to mitotic stages and interphase. Features of the cell cycle, morphology and sizes of metaphase chromosomes, fluorochrome banding patterns, and silver staining of NORs of such an extremely high polyploid organism are reported for the first time. On a whole, karyokinesis appears to be stable and efficient. A comparison with closely related palm taxa reveals that V. gerardii is 38-ploid, and comparison with the closely related genera Butia, Cocos (coconut) and Jubaea shows that Voanioala has lost ∼ 35% of its DNA amount subsequent to polyploidization and has suppressed between 74 and 88% of the original nucleolar organizers. About 10 active NORs are present in the nuclei. An auto- or allopolyploid origin of Voanioala is discussed with respect to currently available nuclear gene data. The biogeographic relations to Jubaeopsis, a closely related, monotypic, apparently likewise relict palm genus from eastern mainland South Africa are discussed. From a cytogenetic point of view, a common polyploid ancestor of both genera is most likely, but the available molecular phylogenetic data are not univocal.


Assuntos
Arecaceae/genética , Cromossomos de Plantas/química , DNA de Plantas/genética , Interfase , Mitose , Poliploidia , Arecaceae/classificação , Ciclo Celular/genética , Bandeamento Cromossômico , Cariotipagem , Madagáscar , Região Organizadora do Nucléolo/ultraestrutura , Filogenia , Filogeografia , Coloração pela Prata , África do Sul
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