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1.
J Sci Food Agric ; 99(11): 5073-5082, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-30980532

RESUMO

BACKGROUND: Pomegranate fruit is an excellent source of bioactive polyphenolics, known to contribute significantly to human health. India is the largest producer of pomegranate in the world and produces the finest quality fruit with highly desirable consumer traits such as soft seeds, low acidity, and attractive fruit and aril color. Knowledge of the extent of variation in key metabolites (sugars, organic acids, phenolics, and anthocyanins) is key to selecting superior genotypes for germplasm improvement. Relevant information with respect to Indian genotypes is scarce. The present study therefore aims to evaluate quantitatively important metabolites in some cultivars and elite germplasm of pomegranate in India. RESULTS: Identification and quantification of primary and secondary metabolites such as sugars, organic acids, vitamin C, polyphenolics, and anthocyanins were conducted using a liquid chromatography - mass spectrometry (LC-MS) platform. Fructose and citric acid were the predominant sugar and organic acid, respectively. Wild genotypes had significantly higher concentrations of organic acids, antioxidant activity, and phenolics, namely punicalagin, ellagic acid, sinapic, and ferulic acid. CONCLUSION: Cyanidin and delphinidin derivatives of anthocyanins were more abundant in red aril commercial genotypes. Results suggest that wild-sour accessions represent a rich source of polyphenolics that can be utilized in future breeding programs to breed healthier varieties, food supplements, and pharmaceutical products. © 2019 Society of Chemical Industry.


Assuntos
Células Germinativas Vegetais/classificação , Lythraceae/química , Lythraceae/metabolismo , Antocianinas/análise , Antocianinas/metabolismo , Ácido Ascórbico/análise , Ácido Ascórbico/metabolismo , Cromatografia Líquida de Alta Pressão , Cor , Frutas/química , Frutas/classificação , Frutas/genética , Frutas/metabolismo , Genótipo , Células Germinativas Vegetais/metabolismo , Índia , Lythraceae/classificação , Lythraceae/genética , Espectrometria de Massas , Polifenóis/análise , Polifenóis/metabolismo , Metabolismo Secundário , Sementes/química , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Açúcares/análise , Açúcares/metabolismo
2.
Am J Bot ; 102(11): 1883-900, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26542845

RESUMO

PREMISE OF THE STUDY: Mosses, very diverse in modern ecosystems, are currently underrepresented in the fossil record. For the pre-Cenozoic, fossil mosses are known almost exclusively from compression fossils, while anatomical preservation, which is much more taxonomically informative, is rare. The Lower Cretaceous of Vancouver Island (British Columbia, Canada) hosts a diverse anatomically preserved flora at Apple Bay. While the vascular plant component of the Apple Bay flora has received much attention, the numerous bryophytes identified at the locality have yet to be characterized. METHODS: Fossil moss gametophytes in more than 20 carbonate concretions collected from the Apple Bay locality on Vancouver Island were studied in serial sections prepared using the cellulose acetate peel technique. KEY RESULTS: We describe Tricosta plicata gen. et sp. nov., a pleurocarpous moss with much-branched gametophytes, tricostate plicate leaves, rhizoid-bearing bases, and delicate gametangia (antheridia and archegonia) borne on specialized branches. A new family of hypnanaean mosses, Tricostaceae fam. nov., is recognized based on the novel combination of characters of T. plicata. CONCLUSIONS: Tricosta plicata reveals pleurocarpous moss diversity unaccounted for in extant floras. This new moss adds the first bryophyte component to an already diverse assemblage of vascular plants described from the Early Cretaceous at Apple Bay and, as the oldest representative of the Hypnanae, provides a hard minimum age for the group (136 Ma).


Assuntos
Briófitas/classificação , Evolução Biológica , Colúmbia Britânica , Briófitas/citologia , Briófitas/genética , Fósseis , Células Germinativas Vegetais/classificação , Células Germinativas Vegetais/citologia , Ilhas , Folhas de Planta/classificação , Folhas de Planta/citologia , Folhas de Planta/genética , Brotos de Planta/classificação , Brotos de Planta/citologia , Brotos de Planta/genética
3.
Rev. biol. trop ; 63(2): 321-332, Apr.-Jun. 2015. ilus, tab
Artigo em Inglês | LILACS, SaludCR | ID: lil-764969

RESUMO

Seed banks play an important role in the resilience of potential anthropogenic areas and are influenced by seasonal variation. The spatial and temporal heterogeneity of the forests influences the richness and density of the soil seed bank, but there is a hypothesis that such influence can be changed in anthropogenic areas, where we expect to find lower richness and seed density in relation to the seed bank of mature forests. The richness and seasonal density of seeds in the soil depth of a young caatinga forest, 17 years after an agricultural activity was abandoned, were evaluated and compared with those of a mature forest. The study was conducted at the Instituto Agronômico de Pernambuco - IPA (Estação Experimental José Nilson de Melo), located in Caruaru, Pernambuco, Brazil, in an area of tropical dry forest, known locally as “caatinga”. The local climate is seasonal, the dry season occurring from September to February and the rainy season concentrated in the remaining months. The average annual rainfall over time (time series of 30 years) is 692mm. In each climatic season (rainy and dry), the seed bank was sampled in 210 20x20cm plots (105 in the leaf litter and 105 at 5cm soil depth). The richness and seed density of the soil samples were evaluated by the method of seedling emergence. The seed bank had 47 species, with a predominance of herbaceous plants. Seasonal variation in richness and seed density in the soil (leaf litter + soil) was not significant, but 42 species of the mature forest were absent from the seed bank of the young forest, despite 17 years of natural regeneration and its proximity to the mature forest. On its own, the soil has greater richness and density of seeds than the leaf litter. The depth of seed deposition in the soil bank of the young forest significantly explained 36% of the species richness and 16% of the seed density, with a significant interaction effect with the climatic season only on species richness, explaining 4% of the variation recorded. The seed density of the young forest (1 277seeds/m²) was greater than that the mature forest indicating that the time abandoned had not yet been sufficient for complete recovery of plant diversity and there is no longer any seed limitation of pioneer species for regeneration of the young forest. Rev. Biol. Trop. 63 (2): 321-332. Epub 2015 June 01.


El banco de semillas juega un papel importante en el potencial de resiliencia de las áreas antropogénicas y sufre influencia de las variaciones estacionales. La heterogeneidad espacial y temporal de los bosques influye en la riqueza y la densidad del banco de semillas del suelo, pero hay una hipótesis de que tal influencia se puede cambiar en las zonas antropogénicas, donde esperaríamos encontrar menor riqueza y densidad de semillas en relación con el banco de semillas de los bosques maduros. La riqueza y la densidad estacional de semillas del espacio vertical del suelo de un bosque joven, con 17 años de abandono de cualquier actividad agrícola, fueron evaluadas y comparadas con las un bosque maduro. El estudio se realizó en el Instituto Agronômico de Pernambuco - IPA (Estação Experimental José Nilson de Melo), situado en Caruarú, Pernambuco, Brasil, en una zona de bosque seco tropical, conocida localmente como “caatinga”. El clima local es estacional, la estación seca ocurre de septiembre a febrero y la estación de lluvias en los meses restantes. La precipitación promedio anual (series de tiempo de 30 años) es 692mm. En cada estación climática (lluviosa y seca), el banco de semillas fue muestreado en 210 parcelas de 20x20cm (105 en la hojarasca a 5cm de profundidad del suelo). La riqueza y densidad de semillas de las muestras del suelo fueron evaluadas por el método de emergencia de plántulas. El banco de semillas presentó 47 especies, con una predominancia de las herbáceas. Las variaciones estacionales de riqueza y densidad de semillas del suelo (hojarasca+suelo) no fueron significativas, pero 42 especies del bosque maduro todavía estaban ausentes en el banco de semillas del bosque joven, apesar de los 17 años de regeneración natural y de su proximidad con el bosque maduro. Aisladamente, el suelo presentó mayor riqueza y densidad de semillas que la hojarasca. La profundidad de depósito de semillas en el banco del suelo del bosque joven explicó significativamente 36% de la riqueza de especies y 16% de la densidad de semillas, con efecto significativo de interacción con la estación climática apenas sobre la riqueza de las especies, explicando más de 4% de la variación registrada. La densidad de semillas del bosque joven (1 277semillas/m²) fue más elevada que la del bosque maduro indicando, que a pesar del poco tiempo de abandono del cultivo, fue suficiente para la recuperación completa de la densidad de semillas.


Assuntos
Regeneração , Florestas , Equilíbrio Ecológico , Células Germinativas Vegetais/classificação , Banco de Sementes/estatística & dados numéricos
4.
Mol Biol Evol ; 32(2): 355-67, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25371433

RESUMO

Alternation of generations, in which the haploid and diploid stages of the life cycle are each represented by multicellular forms that differ in their morphology, is a defining feature of the land plants (embryophytes). Anciently derived lineages of embryophytes grow predominately in the haploid gametophytic generation from apical cells that give rise to the photosynthetic body of the plant. More recently evolved plant lineages have multicellular shoot apical meristems (SAMs), and photosynthetic shoot development is restricted to the sporophyte generation. The molecular genetic basis for this evolutionary shift from gametophyte-dominant to sporophyte-dominant life cycles remains a major question in the study of land plant evolution. We used laser microdissection and next generation RNA sequencing to address whether angiosperm meristem patterning genes expressed in the sporophytic SAM of Zea mays are expressed in the gametophytic apical cells, or in the determinate sporophytes, of the model bryophytes Marchantia polymorpha and Physcomitrella patens. A wealth of upregulated genes involved in stem cell maintenance and organogenesis are identified in the maize SAM and in both the gametophytic apical cell and sporophyte of moss, but not in Marchantia. Significantly, meiosis-specific genetic programs are expressed in bryophyte sporophytes, long before the onset of sporogenesis. Our data suggest that this upregulated accumulation of meiotic gene transcripts suppresses indeterminate cell fate in the Physcomitrella sporophyte, and overrides the observed accumulation of meristem patterning genes. A model for the evolution of indeterminate growth in the sporophytic generation through the concerted selection of ancestral meristem gene programs from gametophyte-dominant lineages is proposed.


Assuntos
Células Germinativas Vegetais/metabolismo , Meristema/metabolismo , Evolução Biológica , Bryopsida/classificação , Bryopsida/metabolismo , Evolução Molecular , Regulação da Expressão Gênica de Plantas , Células Germinativas Vegetais/classificação , Meristema/genética , Proteínas de Plantas/genética
5.
Sheng Wu Gong Cheng Xue Bao ; 28(8): 981-94, 2012 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-23185898

RESUMO

Mei (Prunus mume Sieb.et Zucc.) is traditionally not only a famous special ornamental plant but also a fruit tree origined in China. In order to conserve and ultilize scientifically the germplasm resources of wild mei, we identified and analysed the germplasm of mei flower in 65 samples collected from the habitat, using AFLP makers in combination with morphological anaylsis. This study amplified clearly 1 728 polymorphic bands, using the 8- pair-primer of Mse I -EcoR I screened totally from 64 -primer combination. According to the Nei' 72 distance coefficient clustering, all of the formas and varieties used in this study, including Prunus mume var. mume, P. mume, P. mume var. goethartiana, P. mume var. pallescens, P. mume var. microcarpa, P. mume var. cenrnus-sempervirens (newly recoeding variety), P. mume var. cernua, P. mume var. pallidus, P. mume var. taomei, were identified at the point of Nei' 72=0.26. Due to the genetic difference obviously among the formas and varieties, we suggested that wild germplasmtypes of all formas and varieties in P. mume should be conserved in their habitats in the furture.


Assuntos
Variação Genética , Células Germinativas Vegetais/classificação , Prunus/classificação , Prunus/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Filogenia , Especificidade da Espécie
6.
Mol Phylogenet Evol ; 63(2): 351-64, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22266481

RESUMO

Morphological characters from the gametophyte and sporophyte generations have been used in land plants to infer relationships and construct classifications, but sporophytes provide the vast majority of data for the systematics of vascular plants. In bryophytes both generations are well developed and characters from both are commonly used to classify these organisms. However, because morphological traits of gametophytes and sporophytes can have different genetic bases and experience different selective pressures, taxonomic emphasis on one generation or the other may yield incongruent classifications. The moss order Hookeriales has a controversial taxonomic history because previous classifications have focused almost exclusively on either gametophytes or sporophytes. The Hookeriales provide a model for comparing morphological evolution in gametophytes and sporophytes, and its impact on alternative classification systems. In this study we reconstruct relationships among mosses that are or have been included in the Hookeriales based on sequences from five gene regions, and reconstruct morphological evolution of six sporophyte and gametophyte traits that have been used to differentiate families and genera. We found that the Hookeriales, as currently circumscribed, are monophyletic and that both sporophyte and gametophyte characters are labile. We documented parallel changes and reversals in traits from both generations. This study addresses the general issue of morphological reversals to ancestral states, and resolves novel relationships in the Hookeriales.


Assuntos
Bryopsida/classificação , Bryopsida/genética , Células Germinativas Vegetais/fisiologia , Filogenia , Sequência de Bases , Evolução Biológica , Bryopsida/anatomia & histologia , DNA de Plantas/genética , DNA Espaçador Ribossômico/genética , Evolução Molecular , Células Germinativas Vegetais/classificação , Mitocôndrias/genética , Alinhamento de Sequência , Análise de Sequência de DNA
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