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1.
An Acad Bras Cienc ; 92 Suppl 1: e20180757, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32491136

RESUMO

Pereskia grandifolia Haworth (PGH) and Pereskia aculeata Miller (PAM) are recognized sources of proteins; dietary fiber; vitamins and minerals make this plant leaves, raw, cooked, and braised, an important ally against protein and micronutrient deficiencies. One of the main problems is the presence of antinutritional factors that may interfere in the digestibility and bioavailability of some nutrients. The objective was to evaluate the amino acid profile and the chemical score of the raw leaves and the effects of heating media and time on the total dietary fiber, minerals, trypsin inhibition, oxalic acid and tannins of leaves of PGH and PAM. The samples had similar amino acid profiles and total dietary fiber. With regard to antinutritional compounds, heating the leaves of PGH led to a decrease in trypsin inhibition, primarily after the first minutes of wet cooking. Oxalic acid and tannins predominated in both species. Considering the interaction with time, the variables related to iron and zinc minimized the tannin responses in PGH and PAM, respectively. Heating media and times interfered with the chemical components present in the leaves of Pereskia species and led to high antinutrient retention after heat treatment.


Assuntos
Cactaceae/química , Valor Nutritivo , Verduras/química , Aminoácidos/análise , Cactaceae/classificação , Fibras na Dieta/análise , Manipulação de Alimentos , Minerais/análise , Proteínas/análise , Taninos/análise , Verduras/classificação
2.
An Acad Bras Cienc ; 92(2): e20180836, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32520218

RESUMO

The climate change projections for the Caatinga biome this century are for an increase in temperature and reduction in rainfall, leading to aridization and plant cover dominated by Cactaceae. The objective of this study was to model the potential distribution of Epiphyllum phyllanthus (L.) Haw., a cactus that is native to the Caatinga biome, considering two possible future climate scenarios, to assess this species' spatio-temporal response to these climate change, and thus to evaluate the need or not for conservation measures. For this purpose, we obtained biogeographic information on the target species from biodiversity databases, choosing nine environmental variables and applying the MaxEnt algorithm. We considered the time intervals 2041-2060 and 2061-2080, centered on 2050 and 2070, respectively, and the greenhouse gas scenarios RCP4.5 and 8.5. For all the scenarios considered, the models generated for 2050 and 2070 projected drastic contraction (greater than 80%) for the areas of potential occurrence of the species in relation to the present potential. The remaining areas were found to be concentrated in the northern portion of the biome, specifically in the northern part of the state of Ceará, which has particular characteristics.


Assuntos
Biodiversidade , Cactaceae/fisiologia , Mudança Climática , Ecossistema , Phyllanthus/fisiologia , Cactaceae/classificação , Conservação dos Recursos Naturais , Modelos Biológicos , Phyllanthus/classificação
3.
Protoplasma ; 256(3): 805-814, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30604246

RESUMO

The clade ACPT (Anacampserotaceae, Cactaceae, Portulacaceae, and Talinaceae) is the most diverse lineage of the subordem Cactineae. The relationships between these families are still uncertain, with different topologies suggested by phylogenetic analyses with several combinations of markers. Different basic numbers (x) have been suggested for each family and for the subord, often in a contestable way. Comparative cytogenetic has helped to understand the evolutionary relationships of phylogenetically poorly resolved groups, as well as their mechanisms of karyotype evolution. The karyotype evolution in representatives of Cactineae was analyzed, focusing on the ACPT clade, through the analysis of chromosome number in a phylogenetic bias. The phylogeny obtained showed a well-resolved topology with support for the monophyly of the five families. Although a chromosomal number is known for less than 30% of the Cactineae species, the analyses revealed a high karyotype variability, from 2n = 8 to 2n = 110. The analysis of character reconstruction of the ancestral haploid numbers (p) suggested p = 12 for Cactineae, with distinct basic numbers for the clade family ACPT: Cactaceae and Montiaceae (p = 11), Talinaceae (p = 12), and Anacampserotaceae and Portulacaceae (p = 9). Talinaceae, Anacampserotaceae, and Cactaceae were stable, while Portulaca and Montiaceae were karyotypically variable. The chromosome evolution of this group was mainly due to events of descending disploidy and poliploidy. Our data confirm that the low phylogenetic resolution among the families of the ACPT clade is due to a divergence of this clade in a short period of time. However, each of these families can be characterized by basic chromosome numbers and unique karyotype evolution events.


Assuntos
Cactaceae/classificação , Cactaceae/genética , Caryophyllales/classificação , Caryophyllales/genética , Citogenética , Filogenia , Portulacaceae/classificação , Portulacaceae/genética , Cromossomos de Plantas/genética , Modelos Biológicos
4.
Molecules ; 24(3)2019 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-30691184

RESUMO

The red flesh trait gives red pitayas more healthful components and a higher price, while the genetic mechanism behind this trait is unknown. In this manuscript, transcriptome analysis was employed to discover the genetic differences between white and red flesh in pitayas. A total of 27.99 Gb clean data were obtained for four samples. Unigenes, 79,049 in number, were generated with an average length of 1333 bp, and 52,618 Unigenes were annotated. Compared with white flesh, the expression of 10,215 Unigenes was up-regulated, and 4853 Unigenes were down-regulated in red flesh. The metabolic pathways accounted for 64.6% of all differentially expressed Unigenes in KEGG pathways. The group with high betalain content in red flesh and all structural genes, related to betalain biosynthesis, had a higher expression in red flesh than white flesh. The expression of the key gene, tyrosine hydroxylase CYP76AD1, was up-regulated 245.08 times, while 4,5-DOPA dioxygenase DODA was up-regulated 6.46 times. Moreover, the special isomers CYP76AD1α and DODAα were only expressed in red flesh. The competitive anthocyanin biosynthesis pathway had a lower expression in red flesh. Two MYB transcription factors were of the same branch as BvMYB1, regulating betalain biosynthesis in beet, and those transcription factors had expression differences in two kinds of pitayas, which indicated that they should be candidate genes controlling betalain accumulation in red pitayas. This research would benefit from identifying the major gene controlling red flesh trait and breed new cultivars with the red flesh trait. Future research should aim to prove the role of each candidate gene in betalain biosynthesis in red pitayas.


Assuntos
Betalaínas/biossíntese , Cactaceae/genética , Cactaceae/metabolismo , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Transcriptoma , Antocianinas/biossíntese , Vias Biossintéticas/genética , Cactaceae/classificação , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Genes de Plantas , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia
5.
Genetica ; 146(3): 329-340, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29779125

RESUMO

Endemic, obligate outcrossing plant species with narrow geographic distributions and disjunct populations are prone to loss of genetic diversity. Simultaneously, delineating clear species boundaries is important for targeted conservation efforts. The rare and endemic cactus, Sclerocactus brevihamatus subsp. tobuschii (SBT), has a parapatric relationship with Sclerocactus brevihamatus subsp. brevihamatus (SBB) but genetic distance between the two taxa is unknown. We: (1) developed taxon-specific polymorphic microsatellites, (2) assessed genetic diversity within and among nine populations of SBT, and within one population of SBB, and (3) estimated the genetic relationship between the two subspecies. Within-population genetic diversity of SBT was moderate to high (mean Ho = 0.37; mean He = 0.59). Indirect estimate of inbreeding corrected for null alleles (Fis-INEst) was low for SBT, ranging from 0.03 to 0.14 (mean Fis-INEst = 0.07). Genetic differentiation among populations of SBT was low based on Fst (0.08) and AMOVA (ФPT = 0.10). Lack of genetic and spatial correlation in SBT populations coupled with the presence of private alleles and bottleneck events in several populations suggests that reproductive isolation is occurring but that sufficient time may not have yet passed to manifest strong differentiation. Cluster analyses segregated the 10 populations into three distinct groups, and separated SBB genotypes clearly. Results suggest that while hybridization between the two subspecies may occur, SBT is clearly differentiated genetically from SBB to retain its current taxonomic status.


Assuntos
Cactaceae/classificação , Cactaceae/genética , Variação Genética , Genética Populacional , Alelos , DNA de Plantas , Evolução Molecular , Repetições de Microssatélites , Texas
6.
PLoS One ; 13(4): e0195475, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29630653

RESUMO

Succulent cacti (Cactaceae) are among the most threatened taxonomic groups assessed to date. Here we evaluated the genetic diversity and population structure of a narrow endemic columnar cactus Pilosocereus aureispinus. This species is only found in a small area of c. 300 km2 of rocky savanna from eastern Brazil and it is currently classified as vulnerable (VU) on the International Union for Conservation of Nature (IUCN) red list. Eight microsatellite loci were genotyped for 91 individuals from four localities of the known P. aureispinus range. In contrast with expectations for narrow endemic species, we found relatively high levels of genetic diversity (e.g., HE = 0.390 to 0.525; HO = 0.394 to 0.572) and very low population structure based on the variation of six loci. All the analyzed individuals were clustered in one unique genetic group in assignment tests. We also generated the sequences of two plastid markers (trnT-trnL and psbD-trnT) and found no variation on a subsample of 39 individuals. We used Landsat 8 images and Normalized Difference Vegetation Index to estimate a potential extent of occurrence of c. 750 km2 for this species. Our results showed that P. aureispinus is not suffering from erosion of nuclear genetic variability due to its narrow distribution. However, we advocate that because of the extremely limited extent of occurrence, the ongoing anthropogenic disturbances in its habitat, and phylogenetic distinctiveness of P. aureispinus, this species should be classified as endangered (EN) on the IUCN Red List.


Assuntos
Cactaceae/genética , Espécies em Perigo de Extinção , Brasil , Cactaceae/classificação , Conservação dos Recursos Naturais , DNA de Plantas/genética , Marcadores Genéticos , Variação Genética , Genética Populacional , Pradaria , Repetições de Microssatélites , Filogenia , Filogeografia , Plastídeos/genética
7.
PLoS One ; 13(1): e0190385, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29342184

RESUMO

The Stenocereus griseus species complex (SGSC) has long been considered taxonomically challenging because the number of taxa belonging to the complex and their geographical boundaries remain poorly understood. Bayesian clustering and genetic distance-based methods were used based on nine microsatellite loci in 377 individuals of three main putative species of the complex. The resulting genetic clusters were assessed for ecological niche divergence and areolar morphology, particularly spination patterns. We based our species boundaries on concordance between genetic, ecological, and morphological data, and were able to resolve four species, three of them corresponding to S. pruinosus from central Mexico, S. laevigatus from southern Mexico, and S. griseus from northern South America. A fourth species, previously considered to be S. griseus and commonly misidentified as S. pruinosus in northern Mexico showed significant genetic, ecological, and morphological differentiation suggesting that it should be considered a new species, S. huastecorum, which we describe here. We show that population genetic analyses, ecological niche modeling, and morphological studies are complementary approaches for delimiting species in taxonomically challenging plant groups such as the SGSC.


Assuntos
Cactaceae/classificação , Teorema de Bayes , Cactaceae/genética , Genes de Plantas , Modelos Teóricos , Especificidade da Espécie
8.
Food Chem ; 234: 111-118, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28551213

RESUMO

Pitaya fruits (Stenocereus spp.) contain betalains and phenolic compounds that have not been completely characterized. Fruits of two ecotypes of S. pruinosus, red-fleshed (SpR) and orange-fleshed (SpO), and two of S. stellatus, red-fleshed (SsR) and white-fleshed (SsW), were characterized in their betalains and phenolic compounds. The chromatographic profile of betalains was similar in SpR, SpO, and SsR, where indicaxanthin, gomphrenin I, phyllocacthin, and their isomers predominated. Betaxanthins content was higher than betacyanins and ranged from 17,706.7±1128.1 to 22,053.6±328.1µg/g dry sample. The identified phenolics mostly corresponded to hydroxycinnamoyl derivatives, flavonols and flavanones. The phenolics content was higher in S. stellatus than in S. pruinosus. The ecotype SsW, that had flesh without color, showed the highest concentration. The antioxidant capacity varied within 9.21±0.84 and 2.41±0.36µmolTrolox/g fresh sample, as determined by the ABTS assay. By its phytochemical composition, the fruits of pitaya can be a good source of antioxidant compounds.


Assuntos
Antioxidantes/química , Betalaínas/química , Cactaceae/química , Frutas/química , Fenóis/química , Cactaceae/classificação
9.
PLoS One ; 12(4): e0175905, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28426818

RESUMO

Historic demography changes of plant species adapted to New World arid environments could be consistent with either the Glacial Refugium Hypothesis (GRH), which posits that populations contracted to refuges during the cold-dry glacial and expanded in warm-humid interglacial periods, or with the Interglacial Refugium Hypothesis (IRH), which suggests that populations contracted during interglacials and expanded in glacial times. These contrasting hypotheses are developed in the present study for the giant columnar cactus Cephalocereus columna-trajani in the intertropical Mexican drylands where the effects of Late Quaternary climatic changes on phylogeography of cacti remain largely unknown. In order to determine if the historic demography and phylogeographic structure of the species are consistent with either hypothesis, sequences of the chloroplast regions psbA-trnH and trnT-trnL from 110 individuals from 10 populations comprising the full distribution range of this species were analysed. Standard estimators of genetic diversity and structure were calculated. The historic demography was analysed using a Bayesian approach and the palaeodistribution was derived from ecological niche modelling to determine if, in the arid environments of south-central Mexico, glacial-interglacial cycles drove the genetic divergence and diversification of this species. Results reveal low but statistically significant population differentiation (FST = 0.124, P < 0.001), although very clear geographic clusters are not formed. Genetic diversity, haplotype network and Approximate Bayesian Computation (ABC) demographic analyses suggest a population expansion estimated to have taken place in the Last Interglacial (123.04 kya, 95% CI 115.3-130.03). The species palaeodistribution is consistent with the ABC analyses and indicates that the potential area of palaedistribution and climatic suitability were larger during the Last Interglacial and Holocene than in the Last Glacial Maximum. Overall, these results suggest that C. columna-trajani experienced an expansion following the warm conditions of interglacials, in accordance with the GRH.


Assuntos
Cactaceae/classificação , Ecossistema , Cactaceae/genética , Cactaceae/fisiologia , DNA de Plantas/genética , DNA de Plantas/isolamento & purificação , Genes de Plantas , Haplótipos , México , Modelos Teóricos , Fotossíntese , Clima Tropical
10.
Amino Acids ; 49(5): 821-869, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28299478

RESUMO

Plants are a rich source of amino acids and their individual abundance in plants is of great significance especially in terms of food. Therefore, it is of utmost necessity to create a database of the relative amino acid contents in plants as reported in literature. Since in most of the cases complete analysis of profiles of amino acids in plants was not reported, the units used and the methods applied and the plant parts used were different, amino acid contents were converted into relative units with respect to lysine for statistical analysis. The most abundant amino acids in plants are glutamic acid and aspartic acid. Pearson's correlation analysis among different amino acids showed that there were no negative correlations between the amino acids. Cluster analysis (CA) applied to relative amino acid contents of different families. Alismataceae, Cyperaceae, Capparaceae and Cactaceae families had close proximity with each other on the basis of their relative amino acid contents. First three components of principal component analysis (PCA) explained 79.5% of the total variance. Factor analysis (FA) explained four main underlying factors for amino acid analysis. Factor-1 accounted for 29.4% of the total variance and had maximum loadings on glycine, isoleucine, leucine, threonine and valine. Factor-2 explained 25.8% of the total variance and had maximum loadings on alanine, aspartic acid, serine and tyrosine. 14.2% of the total variance was explained by factor-3 and had maximum loadings on arginine and histidine. Factor-4 accounted 8.3% of the total variance and had maximum loading on the proline amino acid. The relative content of different amino acids presented in this paper is alanine (1.4), arginine (1.8), asparagine (0.7), aspartic acid (2.4), cysteine (0.5), glutamic acid (2.8), glutamine (0.6), glycine (1.0), histidine (0.5), isoleucine (0.9), leucine (1.7), lysine (1.0), methionine (0.4), phenylalanine (0.9), proline (1.1), serine (1.0), threonine (1.0), tryptophan (0.3), tyrosine (0.7) and valine (1.2).


Assuntos
Alismataceae/metabolismo , Aminoácidos/metabolismo , Cactaceae/metabolismo , Capparaceae/metabolismo , Cyperaceae/metabolismo , Alismataceae/classificação , Aminoácidos/isolamento & purificação , Cactaceae/classificação , Capparaceae/classificação , Análise por Conglomerados , Cyperaceae/classificação , Filogenia , Análise de Componente Principal , Especificidade da Espécie
11.
Heredity (Edinb) ; 116(6): 550-7, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27071846

RESUMO

Pilosocereus machrisii and P. aurisetus are cactus species within the P. aurisetus complex, a group of eight cacti that are restricted to rocky habitats within the Neotropical savannas of eastern South America. Previous studies have suggested that diversification within this complex was driven by distributional fragmentation, isolation leading to allopatric differentiation, and secondary contact among divergent lineages. These events have been associated with Quaternary climatic cycles, leading to the hypothesis that the xerophytic vegetation patches which presently harbor these populations operate as refugia during the current interglacial. However, owing to limitations of the standard phylogeographic approaches used in these studies, this hypothesis was not explicitly tested. Here we use Approximate Bayesian Computation to refine the previous inferences and test the role of different events in the diversification of two species within P. aurisetus group. We used molecular data from chloroplast DNA and simple sequence repeats loci of P. machrisii and P. aurisetus, the two species with broadest distribution in the complex, in order to test if the diversification in each species was driven mostly by vicariance or by long-dispersal events. We found that both species were affected primarily by vicariance, with a refuge model as the most likely scenario for P. aurisetus and a soft vicariance scenario most probable for P. machrisii. These results emphasize the importance of distributional fragmentation in these species, and add support to the hypothesis of long-term isolation in interglacial refugia previously proposed for the P. aurisetus species complex diversification.


Assuntos
Evolução Biológica , Cactaceae/genética , Genética Populacional , Filogeografia , Refúgio de Vida Selvagem , Teorema de Bayes , Cactaceae/classificação , Simulação por Computador , DNA de Cloroplastos/genética , DNA de Plantas/genética , Ecossistema , Repetições de Microssatélites , Modelos Genéticos , Dispersão Vegetal , Análise de Sequência de DNA , América do Sul
12.
Rev. bras. plantas med ; 18(1): 81-88, jan.-mar. 2016. tab, graf
Artigo em Espanhol | LILACS | ID: lil-780041

RESUMO

RESUMO No Nordeste do Brasil é bastante comum e variado o uso da coroa-de-frade (Melocactus spp.). Assim, o objetivo deste estudo foi realizar diversas análises em cladódios de coroa-de-frade [Melocactus zehntneri (Britton & Rose) Luetzelburg], para que possamos compreender as razões estes usos. Os cladódios foram coletados na cidade de Campina Grande e levados ao Laboratório de Engenharia de Alimentos da Universidade Federal de Campina Grande, onde foram feitas as seguintes análises: peso, altura, diâmetro, cor, umidade, acidez, pH, ácido ascórbico, carotenoides, flavonoides e compostos fenólicos, tanto na epiderme quanto no parênquima aquífero. Os resultados mostraram que a epiderme tem uma acidez elevada e mais ácido ascórbico, e um pH mais baixo em comparação com o parênquima aquífero. O conteúdo de carotenoides, flavonoides e compostos fenólicos, foram diferentes nas partes estudadas. A epiderme apresentou sempre maiores quantidades de carotenoides, flavonoides e compostos fenólicos em relação ao parênquima aquífero, nas três plantas estudadas, indicando que a maior parte da defesa da planta acontece neste tecido. Mais estudos são necessários com técnicas mais precisas, para identificar os componentes bioativos desta espécie.


ABSTRACT In Northeast Brazil, the use of melon cactus (Melocactus spp.) is quite common and varied. Thus, the present study aimed to perform various analyzes in cladodes of melon cactus [Melocactus zehntneri (Britton & Rose) Luetzelburg], to understand the reasons for the use of this species. The cladodes were collected in the city of Campina Grande and taken to the Food Engineering Laboratory of the Federal University of Campina Grande, where we performed the following analyses: mass, height, diameter, color, moisture, acidity, pH, ascorbic acid, carotenoids, flavonoids and phenolic compounds, both in the epidermis and in the aquifer parenchyma. The results showed that the epidermis has a higher acidity, ascorbic acid content and lower pH compared to the aquifer parenchyma. The contents of carotenoids, flavonoids and phenolic compounds, were different from the both parts analyzed. The epidermis always had greater quantities of carotenoids, flavonoids and phenolic compounds than the aquifer parenchyma for the three plants, showing that most of the plant defense takes place in this tissue. Further studies, with more accurate techniques, are needed to identify the bioactive components of this species.


Assuntos
Cactaceae/classificação , Ácido Ascórbico/análise , Carotenoides/análise , Água Subterrânea , Compostos Fenólicos/análise , Caules de Planta/classificação
13.
Mol Phylogenet Evol ; 95: 11-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26582125

RESUMO

The Pilosocereus aurisetus complex consists of eight cactus species with a fragmented distribution associated to xeric enclaves within the Cerrado biome in eastern South America. The phylogeny of these species is incompletely resolved, and this instability complicates evolutionary analyses. Previous analyses based on both plastid and microsatellite markers suggested that this complex contained species with inherent phylogeographic structure, which was attributed to recent diversification and recurring range shifts. However, limitations of the molecular markers used in these analyses prevented some questions from being properly addressed. In order to better understand the relationship among these species and make a preliminary assessment of the genetic structure within them, we developed anonymous nuclear loci from pyrosequencing data of 40 individuals from four species in the P. aurisetus complex. The data obtained from these loci were used to identify genetic clusters within species, and to investigate the phylogenetic relationship among these inferred clusters using a species tree methodology. Coupled with a palaeodistributional modelling, our results reveal a deep phylogenetic and climatic disjunction between two geographic lineages. Our results highlight the importance of sampling more regions from the genome to gain better insights on the evolution of species with an intricate evolutionary history. The methodology used here provides a feasible approach to develop numerous genealogical molecular markers throughout the genome for non-model species. These data provide a more robust hypothesis for the relationship among the lineages of the P. aurisetus complex.


Assuntos
Cactaceae/classificação , Cactaceae/genética , Núcleo Celular/genética , Dispersão Vegetal , Clima , Marcadores Genéticos , Ilhas , Repetições de Microssatélites , Filogenia , Filogeografia , Plastídeos/genética , Análise de Sequência de DNA , América do Sul
14.
Am J Bot ; 102(9): 1506-20, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26373974

RESUMO

PREMISE OF THE STUDY: Species of the endemic Chilean cactus genus Copiapoa have cylindrical or (sub)globose stems that are solitary or form (large) clusters and typically yellow flowers. Many species are threatened with extinction. Despite being icons of the Atacama Desert and well loved by cactus enthusiasts, the evolution and diversity of Copiapoa has not yet been studied using a molecular approach. METHODS: Sequence data of three plastid DNA markers (rpl32-trnL, trnH-psbA, ycf1) of 39 Copiapoa taxa were analyzed using maximum likelihood and Bayesian inference approaches. Species distributions were modeled based on geo-referenced localities and climatic data. Evolution of character states of four characters (root morphology, stem branching, stem shape, and stem diameter) as well as ancestral areas were reconstructed using a Bayesian and maximum likelihood framework, respectively. KEY RESULTS: Clades of species are revealed. Though 32 morphologically defined species can be recognized, genetic diversity between some species and infraspecific taxa is too low to delimit their boundaries using plastid DNA markers. Recovered relationships are often supported by morphological and biogeographical patterns. The origin of Copiapoa likely lies between southern Peru and the extreme north of Chile. The Copiapó Valley limited colonization between two biogeographical areas. CONCLUSIONS: Copiapoa is here defined to include 32 species and five heterotypic subspecies. Thirty species are classified into four sections and two subsections, while two species remain unplaced. A better understanding of evolution and diversity of Copiapoa will allow allocating conservation resources to the most threatened lineages and focusing conservation action on real biodiversity.


Assuntos
Evolução Biológica , Cactaceae/fisiologia , Cactaceae/classificação , Cactaceae/genética , Chile , DNA de Plantas/genética , DNA de Plantas/metabolismo , Dados de Sequência Molecular , Filogenia , Dispersão Vegetal , Plastídeos/genética , Análise de Sequência de DNA
15.
An Acad Bras Cienc ; 87(2): 765-76, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26131634

RESUMO

The purpose of this study was to evaluate the chemical, physiological and genetic differences in seeds of cactus of the Cereus genus (mandacaru) cultivated in the Northeast (Picos, State of Piauí) and Southern (Maringá, State of Paraná) regions of Brazil. Over a period of eight days, temperatures of 25°C and 30°C were equally efficient for the germination of all the seeds. Oleic acid (C18:1) was the most common fatty acid found in the seeds collected in the Southern (41%) and Northeast (45.5%) regions. The analysis of lipases indicated that seeds from Maringá have high mean observed and expected heterozygosities and that seeds from Picos have a higher number of alleles per loci. Therefore, the seeds of mandacaru from the semiarid region of Northeast as well as the seeds from the South (the two contrasting regions of Brazil) are promising with regards to the preservation of the biodiversity in the genome of mandacaru. The low genetic identity between mandacaru seeds from Maringá and Picos at Lipase-5 locus analysis (I = 0.77) suggests that the mandacaru plants from Maringá and Picos may correspond to two species: C. peruvianus and C. jamacaru, respectively.


Assuntos
Cactaceae/química , Cactaceae/genética , Ácidos Graxos/análise , Sementes/química , Alelos , Brasil , Cactaceae/classificação , Eletroforese em Gel de Poliacrilamida , Reação em Cadeia da Polimerase
16.
Bioinspir Biomim ; 10(3): 036005, 2015 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-25909346

RESUMO

Four species of cacti were chosen for this study: Copiapoa cinerea var. haseltoniana, Ferocactus wislizenii, Mammillaria columbiana subsp. yucatanensis and Parodia mammulosa. It has been reported that dew condenses on the spines of C. cinerea and that it does not on the spines of F. wislizenii, and our preliminary observations of M. columbiana and P. mammulosa revealed a potential for collecting dew water. This study found all four cacti to harvest dew on their stems and spines (albeit rarely on the spines of F. wislizenii). Dew harvesting experiments were carried out in the UK, recording an increase in cacti mass on dewy nights. By applying a ranking relative to a polymethyl methacrylate (Plexiglas) reference plate located nearby, it was found that C. cinerea collected the most airborne moisture followed by M. columbiana, P. mammulosa and F. wislizenii respectively, with mean efficiency ratio with respect to the Plexiglas reference of 3.48 ± 0.5, 2.44 ± 0.06, 1.81 ± 0.14 and 1.27 ± 0.49 on observed dewy nights. A maximum yield of normalized performance of 0.72 ± 0.006 l/m(-2) on one dewy night was recorded for C. cinerea. Removing the spines from M. columbiana was found to significantly decrease its dew harvesting efficiency. The spines of three of the species were found to be hydrophilic in nature, while F. wislizenii was hydrophobic; the stems of all four species were hydrophilic. The results of this study could be translated into designing a biomimetic water collecting device that utilizes cactus spines and their microstructures.


Assuntos
Materiais Biomiméticos/química , Cactaceae/química , Cactaceae/classificação , Caules de Planta/química , Caules de Planta/classificação , Água/química , Adsorção , Teste de Materiais , Especificidade da Espécie
17.
PLoS One ; 10(4): e0123919, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25880223

RESUMO

In Cactaceae, wood anatomy is related to stem morphology in terms of the conferred support. In species of cacti with dimorphic wood, a unique process occurs in which the cambium stops producing wide-band tracheids (WBTs) and produces fibers; this is associated with the aging of individuals and increases in size. Stem support and lignification have only been studied in fibrous tree-like species, and studies in species with WBTs or dimorphic wood are lacking. In this study, we approach this process with a chemical focus, emphasizing the role of wood lignification. We hypothesized that the degree of wood lignification in Cactaceae increases with height of the species and that its chemical composition varies with wood anatomy. To test this, we studied the chemical composition (cellulose, hemicellulose, and lignin content) in 13 species (2 WBTs wood, 3 dimorphic, and 8 fibrous) with contrasting growth forms. We also analyzed lignification in dimorphic and fibrous species to determine the chemical features of WBTs and fibers and their relationship with stem support. The lignin contents were characterized by Fourier transform infrared spectroscopy and high performance liquid chromatography. We found that 11 species have a higher percentage (>35%) of lignin in their wood than other angiosperms or gymnosperms. The lignin chemical composition in fibrous species is similar to that of other dicots, but it is markedly heterogeneous in non-fibrous species where WBTs are abundant. The lignification in WBTs is associated with the resistance to high water pressure within cells rather than the contribution to mechanical support. Dimorphic wood species are usually richer in syringyl lignin, and tree-like species with lignified rays have more guaiacyl lignin. The results suggest that wood anatomy and lignin distribution play an important role in the chemical composition of wood, and further research is needed at the cellular level.


Assuntos
Cactaceae/química , Lignina/análise , Madeira/química , Cactaceae/classificação , Cactaceae/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Filogenia , Caules de Planta/química , Caules de Planta/citologia , Caules de Planta/ultraestrutura , Especificidade da Espécie , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Insect Sci ; 22(3): 360-74, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24619863

RESUMO

The tomentose cochineal scale insect, Dactylopius tomentosus (Lamarck) (Hemiptera: Dactylopiidae), is an important biological control agent against invasive species of Cylindropuntia (Caryophyllales: Cactaceae). Recent studies have demonstrated that this scale is composed of host-affiliated biotypes with differential host specificity and fitness on particular host species. We investigated genetic variation and phylogenetic relationships among D. tomentosus biotypes and provenances to examine the possibility that genetic diversity may be related to their host-use pattern, and whether their phylogenetic relationships would give insights into taxonomic relatedness of their host plants. Nucleotide sequence comparison was accomplished using sequences of the mitochondrial cytochrome c oxidase I (COI) gene. Sequences of individuals from the same host plant within a region were identical and characterized by a unique haplotype. Individuals belonging to the same biotype but from different regions had similar haplotypes. However, haplotypes were not shared between different biotypes. Phylogenetic analysis grouped the monophyletic D. tomentosus into 3 well-resolved clades of biotypes. The phylogenetic relationships and clustering of biotypes corresponded with known taxonomic relatedness of their hosts. Two biotypes, Fulgida and Mamillata, tested positive for Wolbachia (α-Proteobacteria), a common endosymbiont of insects. The Wolbachia sequences were serendipitously detected by using insect-specific COI DNA barcoding primers and are most similar to Wolbachia Supergroup F strains. This study is the first molecular characterization of cochineal biotypes that, together with Wolbachia sequences, contribute to the better identification of the biotypes of cochineal insects and to the biological control of cacti using host-specific biotypes of the scale.


Assuntos
Cactaceae/parasitologia , Hemípteros/genética , Hemípteros/microbiologia , Animais , Agentes de Controle Biológico , Cactaceae/classificação , DNA Bacteriano/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genes Mitocondriais , Variação Genética , Interações Hospedeiro-Parasita , Filogenia , Wolbachia/genética
19.
Ann Bot ; 115(1): 19-26, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25399023

RESUMO

BACKGROUND AND AIMS: In Cactaceae, the areole is the organ that forms the leaves, spines and buds. Apparently, the genus Echinocereus develops enclosed buds that break through the epidermis of the stem adjacent to the areole; this trait most likely represents a synapomorphy of Echinocereus. The development of the areole is investigated here in order to understand the anatomical modifications that lead to internal bud development and to supplement anatomical knowledge of plants that do not behave according to classical shoot theory. METHODS: The external morphology of the areole was documented and the anatomy was studied using tissue clearing, scanning electron microscopy and light microscopy for 50 species that represent the recognized clades and sections of the traditional classification of the genus, including Morangaya pensilis (Echinocereus pensilis). KEY RESULTS: In Echinocereus, the areole is sealed by the periderm, and the areole meristem is moved and enclosed by the differential growth of the epidermis and surrounding cortex. The enclosed areole meristem is differentiated in a vegetative or floral bud, which develops internally and breaks through the epidermis of the stem. In Morangaya pensilis, the areole is not sealed by the periderm and the areole meristem is not enclosed. CONCLUSIONS: The enclosed areole meristem and internal bud development are understood to be an adaptation to protect the meristem and the bud from low temperatures. The anatomical evidence supports the hypothesis that the enclosed bud represents one synapomorphy for Echinocereus and also supports the exclusion of Morangaya from Echinocereus.


Assuntos
Cactaceae/crescimento & desenvolvimento , Meristema/crescimento & desenvolvimento , Adaptação Fisiológica , Cactaceae/anatomia & histologia , Cactaceae/classificação , Cactaceae/ultraestrutura , Meristema/anatomia & histologia , Meristema/ultraestrutura , Microscopia Eletrônica de Varredura , Morfogênese , Especificidade da Espécie
20.
J Agric Food Chem ; 62(34): 8764-71, 2014 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-25101804

RESUMO

Metabolite profiling of red and white pitayas (Hylocereus polyrhizus and Hylocereus undatus) was performed using gas chromatography-time-of-flight-mass spectrometry and ultraperformance liquid chromatography-quadrupole-time-of-flight-mass spectrometry with multivariate analysis. Different species and parts of pitayas (red peel, RP; white peel, WP; red flesh, RF; and white flesh, WF) were clearly separated by partial least-squares discriminate analysis. Furthermore, betalain-related metabolites, such as betacyanins and betaxanthins, or their precursors were described on the basis of their metabolites. The results of antioxidant activity tests [1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), and ferric reducing ability of plasma (FRAP)], total phenolic contents (TPC), total flavonoid contents (TFC), and total betacyanin contents (TBC) showed the following: RP ≥ WP > RF > WF. TPC, TFC, TBC, and betalain-related metabolites were higher in the peel than in the flesh and suggested to be the main contributors to antioxidant activity in pitayas. Therefore, peels as well as pulp of pitaya could beneficially help in the food industry.


Assuntos
Antioxidantes/química , Betalaínas/biossíntese , Cactaceae/metabolismo , Extratos Vegetais/química , Antioxidantes/metabolismo , Cactaceae/química , Cactaceae/classificação , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Flavonoides/metabolismo , Frutas/química , Frutas/metabolismo , Espectrometria de Massas , Metabolômica , Extratos Vegetais/metabolismo , Polifenóis/química , Polifenóis/metabolismo
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