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1.
Braz. J. Pharm. Sci. (Online) ; 59: e23011, 2023. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1505852

RESUMEN

Abstract Oil-in-water photoprotective nanoemulsions (NEs) were developed using Babassu (BBS) lipophilic extract, nonionic surfactants, and low concentrations of organic sunscreens by ultrasonic processing. BBS extract was chosen due to its suitable physicochemical properties (acidity index, peroxide index, refraction index, and relative density) and predominance of saturated fatty acids, identified by gas chromatography-mass spectrometry (GC-MS), which promote biological activities and high oxidative stability. NEs were characterized by mean droplet size, morphology, polydispersity index (PdI), pH, and organoleptic properties, and the physical stability of the NEs was evaluated for 120 days at room temperature. The sun protection factor (SPF) was determined, and the photostability and in vitro cytotoxicity assays were performed for NEs. All NEs remained stable for 120 days, with a droplet size <150 nm and a monomodal distribution profile. The pH values were compatible with the skin's pH. NE3 showed a spherical morphology, with a mean droplet size of 125.15 ± 0.16 nm and PdI of 0.145 ± 0.032. NE3 containing BBS extract and sunscreens presented an SPF of 35.5 ± 3.0, was photostable after 6 h of radiation and was non-cytotoxic to fibroblast cells. Thus, NE3 could be considered a promising formulation for developing synergic plant-extract sunscreen photoprotective products for the market


Asunto(s)
Plantas/efectos adversos , Protectores Solares/farmacología , Extractos Vegetales/agonistas , Arecaceae/clasificación , Grasas Vegetales , Técnicas In Vitro/métodos , Factor de Protección Solar/clasificación , Cromatografía de Gases y Espectrometría de Masas/métodos
2.
Rev. biol. trop ; 70(1)dic. 2022.
Artículo en Inglés | LILACS, SaludCR | ID: biblio-1387702

RESUMEN

Abstract Introduction: The natural ecosystems of northern Mato Grosso, Brazil, are in process of fragmentation, mainly due to population growth and the expansion of agriculture. This endangers the palm Euterpe precatoria (locally known as açaí), used for construction, palm hearts, juices and ice cream. Objective: To evaluate the local diversity and genetic structure in native populations of E. precatoria. Methods: We collected leaves from 106 fruiting palms from five populations in Mato Grosso State, for analysis of microsatellite markers with Polymerase Chain Reaction. Results: The five SSR loci revealed a total of 30 alleles, ranging from 5 (EE23 and EE43) to 7 (EE2 and EE15), with an average of 6 alleles per locus. The mean PIC was 0.74 and confirmed low heterozygosity and inbreeding. The UPGMA dendrogram produced two groups and molecular variance revealed greater genetic differentiation within populations. The high levels of homozygous microsatellite loci indicate low genetic diversity. Conclusions: These populations have low gene diversity, high average number of alleles per locus, and rare and exclusive alleles. We recommend the establishment of permanent conservation units with corridors among them.


Resumen Introducción: Los ecosistemas naturales del norte de Mato Grosso, Brasil, están en proceso de fragmentación, principalmente debido al crecimiento de la población y la expansión de la agricultura. Esto pone en peligro la palma Euterpe precatoria (localmente conocida como açaí), utilizada para la construcción, extracción de palmito, preparación de jugos y helados. Objetivo: Evaluar la diversidad local y estructura genética en poblaciones nativas de E. precatoria. Métodos: Recolectamos hojas de 106 palmas fructíferas de cinco poblaciones en el estado de Mato Grosso, para análisis de marcadores microsatélites con el método de Reacción en Cadena de la Polimerasa (PCR). Resultados: Los cinco loci SSR revelaron un total de 30 alelos, que van desde 5 (EE23 y EE43) hasta 7 (EE2 y EE15), con un promedio de 6 alelos por locus. El PIC medio fue de 0.74 y confirmó baja heterocigosidad y endogamia en las poblaciones. El dendrograma UPGMA produjo dos grupos y la varianza molecular reveló una mayor diferenciación genética dentro de las poblaciones. Los loci de microsatélites presentaron un alto nivel de homocigotos lo que indica una baja diversidad genética. Conclusiones: Estas poblaciones tienen baja diversidad genética, alto promedio de alelos por locus y alelos raros y únicos. Recomendamos el establecimiento de unidades de conservación permanentes con corredores entre ellas.


Asunto(s)
Arecaceae/clasificación , Euterpe/clasificación , Brasil
3.
PLoS One ; 16(8): e0256373, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34428237

RESUMEN

The family Arecaceae is distributed throughout tropical and subtropical regions of the world. Among the five subfamilies, Arecoideae is the most species-rich and still contains some ambiguous inter-generic relationships, such as those within subtribes Attaleinae and Bactridineae. The hypervariable regions of plastid genomes (plastomes) are interesting tools to clarify unresolved phylogenetic relationships. We sequenced and characterized the plastome of Bactris gasipaes (Bactridinae) and compared it with eight species from the three Cocoseae sub-tribes (Attaleinae, Bactridinae, and Elaeidinae) to perform comparative analysis and to identify hypervariable regions. The Bactris gasipaes plastome has 156,646 bp, with 113 unique genes. Among them, four genes have an alternative start codon (cemA, rps19, rpl2, and ndhD). Plastomes are highly conserved within tribe Cocoseae: 97.3% identity, length variation of ~2 kb, and a single ~4.5 kb inversion in Astrocaryum plastomes. The LSC/IR and IR/SSC junctions vary among the subtribes: in Bactridinae and Elaeidinae the rps19 gene is completely contained in the IR region; in the subtribe Attaleinae the rps19 gene is only partially contained in the IRs. The hypervariable regions selected according to sequence variation (SV%) and frequency of parsimony informative sites (PIS%) revealed plastome regions with great potential for molecular analysis. The ten regions with greatest SV% showed higher variation than the plastid molecular markers commonly used for phylogenetic analysis in palms. The phylogenetic trees based on the plastomes and the hypervariable regions (SV%) datasets had well-resolved relationships, with consistent topologies within tribe Cocoseae, and confirm the monophyly of the subtribes Bactridinae and Attaleinae.


Asunto(s)
Arecaceae/genética , Evolución Molecular , Plastidios/genética , Arecaceae/clasificación , Hibridación Genómica Comparativa , ADN de Plantas/química , ADN de Plantas/genética , ADN de Plantas/metabolismo , Genoma de Plastidios , Filogenia , Plastidios/clasificación , Análisis de Secuencia de ADN
4.
Plant Mol Biol ; 105(4-5): 559-574, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33386578

RESUMEN

KEY MESSAGE: The plastomes of E. edulis and E. oleracea revealed several molecular markers useful for genetic studies in natural populations and indicate specific evolutionary features determined by vicariant speciation. Arecaceae is a large and diverse family occurring in tropical and subtropical ecosystems worldwide. E. oleracea is a hyperdominant species of the Amazon forest, while E. edulis is a keystone species of the Atlantic forest. It has reported that E. edulis arose from vicariant speciation after the emergence of the belt barrier of dry environment (Cerrado and Caatinga biomes) between Amazon and Atlantic forests, isolating the E. edulis in the Atlantic forest. We sequenced the complete plastomes of E. edulis and E. oleracea and compared them concerning plastome structure, SSRs, tandem repeats, SNPs, indels, hotspots of nucleotide polymorphism, codon Ka/Ks ratios and RNA editing sites aiming to investigate evolutionary traits possibly affected by distinct environments. Our analyses revealed 303 SNPs, 91 indels, and 82 polymorphic SSRs among both species. Curiously, the narrow correlation among localization of repetitive sequences and indels strongly suggests that replication slippage is involved in plastid DNA mutations in Euterpe. Moreover, most non-synonymous substitutions represent amino acid variants in E. edulis that evolved specifically or in a convergent manner across the palm phylogeny. Amino acid variants observed in several plastid proteins in E. edulis were also identified as positive signatures across palm phylogeny. The higher incidence of specific amino acid changes in plastid genes of E. edulis in comparison with E. oleracea probably configures adaptive genetic variations determined by vicariant speciation. Our data indicate that the environment generates a selective pressure on the plastome making it more adapted to specific conditions.


Asunto(s)
Euterpe/genética , Evolución Molecular , Bosques , Genoma de Plastidios/genética , Adaptación Fisiológica/genética , Arecaceae/clasificación , Arecaceae/genética , Proteínas de Cloroplastos/genética , Proteínas de Cloroplastos/metabolismo , ADN de Cloroplastos/análisis , ADN de Cloroplastos/genética , Ecosistema , Euterpe/clasificación , Genes del Cloroplasto/genética , Repeticiones de Microsatélite/genética , Mutación , Filogenia , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN , Especificidad de la Especie
5.
Mol Phylogenet Evol ; 157: 107067, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33412273

RESUMEN

Well-supported phylogenies are a prerequisite for the study of the evolution and diversity of life on earth. The subfamily Calamoideae accounts for more than one fifth of the palm family (Arecaceae), occurs in tropical rainforests across the world, and supports a billion-dollar industry in rattan products. It contains ca. 550 species in 17 genera, 10 subtribes and three tribes, but their phylogenetic relationships remain insufficiently understood. Here, we sequenced almost one thousand nuclear genomic regions for 75 systematically selected Calamoideae, representing the taxonomic diversity within all calamoid genera. Our phylogenomic analyses resolved a maximally supported phylogenetic backbone for the Calamoideae, including several higher-level relationships not previously inferred. In-depth analysis revealed low gene tree conflict for the backbone but complex deep evolutionary histories within several subtribes. Overall, our phylogenomic framework sheds new light on the evolution of palms and provides a robust foundation for future comparative studies, such as taxonomy, systematics, biogeography, and macroevolutionary research.


Asunto(s)
Arecaceae/clasificación , Arecaceae/genética , Filogenia , Secuencia de Bases , Biodiversidad , Núcleo Celular/genética , Exones/genética , Marcadores Genéticos , Genómica
6.
Sci Rep ; 10(1): 21125, 2020 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-33273647

RESUMEN

Isolated islands, due to the reduced interspecific competition compared to mainland habitats, present ecological opportunities for colonizing lineages. As a consequence, island lineages may be expected to experience higher rates of trait evolution than mainland lineages. However, island effects on key life-history traits of vascular plants remain underexplored at broad spatiotemporal scales, even for emblematic island clades such as palms. Here, we used phylogenetic comparative methods to evaluate potential differences in size and macroevolutionary patterns of height and fruit diameter among mainland, continental, and volcanic island palms. Further, phylogenetic beta-diversity was used to determine if lineage turnover supported an adaptive radiation scenario on volcanic islands. Volcanic island palms were taller than their continental island and mainland counterparts, whereas continental island palms exhibited smaller fruit size. Height and fruit size of palms evolved under evolutionary constraints towards an optimal value. However, scenarios of adaptive radiation and niche conservatism were not supported for the height and fruit size of volcanic and mainland palm clades, respectively, as expected. Instead, continental island palms exhibited higher evolutionary rates for height and fruit size. Insular palm assemblages (continental and volcanic) are composed of unique lineages. Beyond representing evolutionary sources of new palm lineages, our results demonstrate that insular habitats are important in shaping palm trait diversity. Also, the higher phenotypic evolutionary rates of continental island palms suggest disparate selection pressures on this habitat type, which can be an important driver of trait diversification over time. Taken together, these results stress the importance of insular habitats for conservation of functional, phylogenetic, and taxonomic diversity of palms.


Asunto(s)
Arecaceae/fisiología , Evolución Biológica , Arecaceae/clasificación , Biodiversidad , Ecosistema , Islas , Filogenia
7.
Commun Biol ; 3(1): 749, 2020 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-33299067

RESUMEN

Plants and their specialized flower visitors provide valuable insights into the evolutionary consequences of species interactions. In particular, antagonistic interactions between insects and plants have often been invoked as a major driver of diversification. Here we use a tropical community of palms and their specialized insect flower visitors to test whether antagonisms lead to higher population divergence. Interactions between palms and the insects visiting their flowers range from brood pollination to florivory and commensalism, with the latter being species that feed on decaying-and presumably undefended-plant tissues. We test the role of insect-host interactions in the early stages of diversification of nine species of beetles sharing host plants and geographical ranges by first delimiting cryptic species and then using models of genetic isolation by environment. The degree to which insect populations are structured by the genetic divergence of plant populations varies. A hierarchical model reveals that this variation is largely uncorrelated with the kind of interaction, showing that antagonistic interactions are not associated with higher genetic differentiation. Other aspects of host use that affect plant-associated insects regardless of the outcomes of their interactions, such as sensory biases, are likely more general drivers of insect population divergence.


Asunto(s)
Arecaceae/parasitología , Gorgojos/genética , Gorgojos/fisiología , Animales , Arecaceae/clasificación , Especiación Genética , Interacciones Huésped-Parásitos , Análisis de Componente Principal
8.
PLoS One ; 15(7): e0235569, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32735584

RESUMEN

The palm family (Arecaceae) is of high ecological and economic value, yet identification in the family remains a challenge for both taxonomists and horticulturalists. The family consists of approximately 2600 species across 181 genera and DNA barcoding may be a useful tool for species identification within the group. However, there have been few systematic evaluations of DNA barcodes for the palm family. In the present study, five DNA barcodes (rbcL, matK, trnH-psbA, ITS, ITS2) were evaluated for species identification ability across 669 samples representing 314 species and 100 genera in the Arecaceae, employing four analytical methods. The ITS gene region was found to not be a suitable barcode for the palm family, due in part, to low recovery rates and paralogous gene copies. Among the four analyses used, species resolution for ITS2 was much higher than that achieved with the plastid barcodes alone (rbcL, matK, trnH-psbA), and the barcode combination ITS2 + matK + rbcL gave the highest resolution among all single barcodes and their combinations, followed by ITS2 + matK. Among 669 palm samples analyzed, 110 samples (16.3%) were found to be misidentified. The 2992 DNA barcode sequences generated in this study greatly enriches the existing identification toolbox available to plant taxonomists that are interested in researching genetic relationships among palm taxa as well as for horticulturalists that need to confirm palm collections for botanical garden curation and horticultural applications. Our results indicate that the use of the ITS2 DNA barcode gene region provides a useful and cost-effective tool to confirm the identity of taxa in the Palm family.


Asunto(s)
Arecaceae/clasificación , Arecaceae/genética , Código de Barras del ADN Taxonómico , Jardines
9.
Genes Genomics ; 42(5): 597-608, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32246355

RESUMEN

BACKGROUND: Microsatellites or simple sequence repeats (SSRs) have become the most significant DNA marker technology used in genetic research. The availability of complete draft genomes for a number of Palmae species has made it possible to perform genome-wide analysis of SSRs in these species. Palm trees are tropical and subtropical plants with agricultural and economic importance due to the nutritional value of their fruit cultivars. OBJECTIVE: This is the first comprehensive study examining and comparing microsatellites in completely-sequenced draft genomes of Palmae species. METHODS: We identified and compared perfect SSRs with 1-6 bp nucleotide motifs to characterize microsatellites in Palmae species using PERF v0.2.5. We analyzed their relative abundance, relative density, and GC content in five palm species: Phoenix dactylifera, Cocos nucifera, Calamus simplicifolius, Elaeis oleifera, and Elaeis guineensis. RESULTS: A total of 118241, 328189, 450753, 176608, and 70694 SSRs were identified, respectively. The six repeat types were not evenly distributed across the five genomes. Mono- and dinucleotide SSRs were the most abundant, and GC content was highest in tri- and hexanucleotide SSRs. CONCLUSION: We envisage that this analysis would further substantiate more in-depth computational, biochemical, and molecular studies on the roles SSRs may play in the genome organization of the palm species. The current study contributes a detailed characterization of simple sequence repeats in palm genomes.


Asunto(s)
Arecaceae/genética , Repeticiones de Microsatélite , Arecaceae/clasificación , Genoma de Planta , Filogenia
10.
Lett Appl Microbiol ; 70(3): 143-150, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31785004

RESUMEN

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.


Asunto(s)
Arecaceae/microbiología , Marasmius/patogenicidad , Enfermedades de las Plantas/microbiología , Arecaceae/clasificación , Aceite de Palma , Plantones/microbiología , Taiwán , Árboles
11.
Genomics ; 112(1): 1011-1020, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31226486

RESUMEN

The genotyping-based sequencing (GBS) method used for GWAS of four yield and seven oil yield related traits on highly diverse African oil palm germplasm. GBS generated 325 million-reads covering 50.78Gb of sequence data, with an average of 3.4 million-reads per sample. Finally, 4031 fully informative SNPs with a range between 157 on chromosome 15 to 455 on chromosome 1 were used for GWAS. Association mapping resulted in identification of 40 highly significant loci, where more genetic loci were found to be associated with oil to bunch (OB), followed by average bunch weight (ABW). The loci, SGI|593,593|linked to QTNOB3 explained high amount of phenotypic variance (25.3%). The nucleotide sequences of linked genetic loci for OB were found to be similar to mitogen activated protein kinase-5 (MAPK-5) protein which is an early flowering protein. The significant loci identified can be used to select desirable palms at early stage through marker assisted selection.


Asunto(s)
Arecaceae/genética , Aceite de Palma , Polimorfismo de Nucleótido Simple , Arecaceae/clasificación , Genes de Plantas , Estudio de Asociación del Genoma Completo , Técnicas de Genotipaje , Desequilibrio de Ligamiento , Fenotipo , Filogenia , Recombinación Genética , Análisis de Secuencia de ADN
12.
Molecules ; 24(23)2019 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-31766411

RESUMEN

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.


Asunto(s)
Antioxidantes/análisis , Arecaceae/química , Elementos Químicos , Ácidos Grasos/análisis , Aceites de Plantas/análisis , Aceites de Plantas/aislamiento & purificación , Arecaceae/clasificación , Manipulación de Alimentos , Humanos , Estrés Oxidativo , Aceites de Plantas/química , Semillas/química
13.
G3 (Bethesda) ; 9(8): 2377-2393, 2019 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-31167834

RESUMEN

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.


Asunto(s)
Arecaceae/clasificación , Arecaceae/genética , Cocos/clasificación , Cocos/genética , Variación Genética , Genoma de Planta , Genómica , Arecaceae/metabolismo , Arecaceae/parasitología , Cocos/metabolismo , Cocos/parasitología , Biología Computacional/métodos , Resistencia a la Enfermedad/genética , Marcadores Genéticos , Genómica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento , Anotación de Secuencia Molecular , Filogenia , Aceites de Plantas/metabolismo , Estrés Fisiológico
14.
Mol Ecol Resour ; 19(1): 221-234, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30240120

RESUMEN

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.


Asunto(s)
Arecaceae/clasificación , Arecaceae/genética , Marcadores Genéticos , Variación Genética , Genética de Población/métodos , Técnicas de Genotipaje/métodos , Biología Computacional , Evolución Molecular , Genoma de Planta , Genotipo , Biología Molecular/métodos , Secuenciación Completa del Genoma
15.
Ann Bot ; 123(4): 641-655, 2019 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-30395146

RESUMEN

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.


Asunto(s)
Arecaceae , Biodiversidad , Inundaciones , Bosque Lluvioso , Suelo/química , Arecaceae/clasificación , Bolivia , Brasil , Colombia , Ecuador , Perú , Filogenia
16.
Mol Phylogenet Evol ; 133: 67-81, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30594734

RESUMEN

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.


Asunto(s)
Arecaceae/clasificación , Arecaceae/genética , América Central , Ecosistema , Filogenia , Filogeografía , Bosque Lluvioso , América del Sur
17.
An Acad Bras Cienc ; 90(4): 3615-3624, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30184010

RESUMEN

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).


Asunto(s)
Arecaceae/anatomía & histología , Color , Hojas de la Planta/crecimiento & desarrollo , Luz Solar , Arecaceae/clasificación , Arecaceae/crecimiento & desarrollo , Arecaceae/efectos de la radiación , Brasil , Fotosíntesis/efectos de la radiación , Hojas de la Planta/anatomía & histología , Hojas de la Planta/efectos de la radiación
18.
Heredity (Edinb) ; 121(2): 183-195, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29588509

RESUMEN

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.


Asunto(s)
Arecaceae/genética , Evolución Biológica , Demografía , Variación Genética , Genética de Población , Árboles/genética , Arecaceae/clasificación , Simulación por Computador , Haplotipos , Repeticiones de Microsatélite
19.
Genet Mol Res ; 16(3)2017 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-28873204

RESUMEN

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.


Asunto(s)
Arecaceae/genética , Frecuencia de los Genes , Desequilibrio de Ligamiento , Polimorfismo Genético , Arecaceae/clasificación , Evolución Molecular , Flujo Génico , Heterocigoto , Repeticiones de Microsatélite
20.
J Agric Food Chem ; 65(34): 7476-7482, 2017 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-28756671

RESUMEN

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.


Asunto(s)
Arecaceae/química , Frutas/química , Aceites de Plantas/química , Tocoferoles/química , Tocotrienoles/química , Arecaceae/clasificación , Cromatografía Líquida de Alta Presión , Costa Rica , Frutas/clasificación , Cromatografía de Gases y Espectrometría de Masas , Aceite de Palma , Aceites de Plantas/aislamiento & purificación , Tocoferoles/aislamiento & purificación , Tocotrienoles/aislamiento & purificación
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