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1.
Molecules ; 28(19)2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37836786

RESUMO

Olive drupe traits (i.e., ripening index and pericarp water content) and minor components (i.e., phenols and pigments in both fruit and oil) are important for human health and are affected by agronomic background. The aim of this study was to investigate the relationship between fruit traits, phenols, and pigments in samples derived from different soil and water management practices. Chromatographic (UHPLC-MS/MS) and spectroscopic (1HNMR and near UV-Vis spectroscopy) techniques were employed for the characterization of olive fruits and oils. The use of various techniques allowed the identification of interesting trace compounds. We observed that most of the fruit phenols (a total of 29 compounds) were correlated with the degree of ripening: most of the phenolic acids (and their derivatives), phenolic alcohols, and secoiridoids were negatively correlated, whereas the majority of the studied flavonoids were positively correlated. The relationship between the ripening index and fruit phenolic compounds appears to be dependent on the metabolic pathway that controls the synthesis of each individual compound. Conversely, the secoiridoids and pigments in olive oil showed a negative correlation with pulp moisture, probably because of the influence of the water content on the extractability and transfer in the oil phase of these minor components.


Assuntos
Olea , Humanos , Olea/química , Frutas/química , Iridoides/análise , Espectrometria de Massas em Tandem , Álcoois/análise , Flavonoides/análise , Água/análise , Azeite de Oliva/química , Fenóis/química , Óleos de Plantas/química
2.
Plant Physiol ; 180(3): 1614-1628, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31019003

RESUMO

Poplar (Populus spp.) is a tree species considered for the remediation of soil contaminated by metals, including zinc (Zn). To improve poplar's capacity for Zn assimilation and compartmentalization, it is necessary to understand the physiological and biochemical mechanisms that enable these features as well as their regulation at the molecular level. We observed that the molecular response of poplar roots to Zn excess overlapped with that activated by hypoxia. Therefore, we tested the effect of Zn excess on hypoxia-sensing components and investigated the consequence of root hypoxia on poplar fitness and Zn accumulation capacity. Our results suggest that high intracellular Zn concentrations mimic iron deficiency and inhibit the activity of the oxygen sensors Plant Cysteine Oxidases, leading to the stabilization and activation of ERF-VII transcription factors, which are key regulators of the molecular response to hypoxia. Remarkably, excess Zn and waterlogging similarly decreased poplar growth and development. Simultaneous excess Zn and waterlogging did not exacerbate these parameters, although Zn uptake was limited. This study unveils the contribution of the oxygen-sensing machinery to the Zn excess response in poplar, which may be exploited to improve Zn tolerance and increase Zn accumulation capacity in plants.


Assuntos
Cisteína Dioxigenase/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Populus/metabolismo , Zinco/metabolismo , Adaptação Fisiológica/genética , Anaerobiose , Biodegradação Ambiental , Cisteína Dioxigenase/genética , Regulação da Expressão Gênica de Plantas , Espaço Intracelular/metabolismo , Proteínas de Plantas/genética , Raízes de Plantas/genética , Populus/genética
3.
Plant Cell Rep ; 39(7): 971-982, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32314047

RESUMO

KEY MESSAGE: Poplar callus maintained a specific difference in osmotic potential with respect to media when supplemented with different carbohydrate concentrations. This balance in osmotic potential guaranteed the growth capacity. Osmotic stress is caused by several abiotic factors such as drought, salinity, or freezing. However, the threshold of osmotic potential that allows the growth under stress conditions has not been thoroughly studied. In this study, different levels of osmotic stress in Populus alba (L.) callus have been induced with the addition of mannitol or sorbitol in the medium (from 0 to 500 mM). The key factor for preserving the growth was observed to be the restoration of a constant difference in osmotic potential between callus and medium for all the tested conditions. The osmotic adjustments were primarily achieved with the uptake of mannitol or sorbitol from the media considering their chemical properties instead of their biological functions. The decrease in water content (from - 1 to - 10% after 21 days) and mineral elements, such as potassium, calcium, and magnesium, together with the alterations in cell morphology, did not show negative effects on growth. The activity of sorbitol dehydrogenase was detected for the first time in poplar (+ 4.7 U l-1 in callus treated with sorbitol compared to control callus). This finding suggested the importance of choosing carefully the molecules used to exert osmotic stress for separating the dual function of carbohydrates in osmotic adjustments and cell metabolism.


Assuntos
Carboidratos/farmacologia , Pressão Osmótica , Populus/citologia , Proliferação de Células/efeitos dos fármacos , Parede Celular/metabolismo , Parede Celular/ultraestrutura , Células Cultivadas , Meios de Cultura , Congelamento , L-Iditol 2-Desidrogenase/metabolismo , Manitol/metabolismo , Minerais/metabolismo , Populus/ultraestrutura , Análise de Componente Principal , Análise de Regressão , Solubilidade , Sorbitol/metabolismo , Amido/metabolismo , Açúcares/metabolismo , Água/metabolismo
4.
J Exp Bot ; 69(16): 4083-4097, 2018 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-29846657

RESUMO

Drought dramatically affects wood production by adversely impacting cambial cells and their derivatives. Photosynthesis and assimilate transport are also affected by drought conditions. Two poplar genotypes, Populus deltoides 'Dvina' and Populus alba 'Marte', demonstrated contrasting growth performance and water-carbon balance strategies; a mechanistic understanding of the water deficit response was provided by these poplar species. 'Marte' was found to be more anisohydric than 'Dvina'. This characteristic was associated with the capacity to reallocate carbohydrates during water deficits. In contrast, 'Dvina' displayed more conservative water management; carbohydrates were preferably stored or used for cellulose production rather than to achieve an osmotic balance between the phloem and the xylem. Data confirmed that the more 'risk-taking' characteristic of 'Marte' allowed a rapid recovery following water deficit and was connected to a different carbohydrate metabolism.


Assuntos
Secas , Populus/metabolismo , Açúcares/metabolismo , Água , Ciclo Celular , Genótipo , Populus/citologia , Populus/genética
5.
Plant Cell Rep ; 35(2): 289-301, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26518428

RESUMO

KEY MESSAGE: Transgenic Populus alba over-expressing a TIP aquaporin ( aqua1) showed a higher growth rate under Zn excess, suggesting that aqua1 could be involved in water homeostasis, rather than in Zn homeostasis. Populus is the internationally accepted model for physiological and developmental studies of tree traits under stress. In plants, aquaporins facilitate and regulate the diffusion of water, however, few poplar aquaporins have been characterized to date. In this study, we reported for the first time an in vivo characterization of Populus alba clone Villafranca transgenic plants over-expressing a TIP aquaporin (aqua1) of P. x euramericana clone I-214. An AQUA1:GFP chimeric construct, over-expressed in P. alba Villafranca clones, shows a cytoplasmic localization in roots, and it localizes in guard cells in leaves. When over-expressed in transgenic plants, aqua1 confers a higher growth rate compared to wild-type (wt) plants, without affecting chlorophyll accumulation, relative water content (RWC), and fluorescence performances, but increasing the intrinsic Transpiration Efficiency. In response to Zn (1 mM), transgenic lines did not show a significant increase in Zn accumulation as compared to wt plants, even though the over-expression of this gene confers higher tolerance in root tissues. These results suggest that, in poplar plants, this gene could be principally involved in regulation of water homeostasis and biomass production, rather than in Zn homeostasis.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Populus/genética , Zinco/metabolismo , Fotossíntese/fisiologia , Proteínas de Plantas/metabolismo , Populus/crescimento & desenvolvimento , Populus/metabolismo
6.
J Exp Bot ; 65(12): 3143-56, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24799563

RESUMO

The hypothesis that aquaporins and carbonic anhydrase (CA) are involved in the regulation of stomatal (g s) and mesophyll (g m) conductance to CO2 was tested in a short-term water-stress and recovery experiment in 5-year-old olive plants (Olea europaea) growing outdoors. The evolution of leaf gas exchange, chlorophyll fluorescence, and plant water status, and a quantitative analysis of photosynthesis limitations, were followed during water stress and recovery. These variables were correlated with gene expression of the aquaporins OePIP1.1 and OePIP2.1, and stromal CA. At mild stress and at the beginning of the recovery period, stomatal limitations prevailed, while the decline in g m accounted for up to 60% of photosynthesis limitations under severe water stress. However, g m was restored to control values shortly after rewatering, facilitating the recovery of the photosynthetic rate. CA was downregulated during water stress and upregulated after recovery. The use of structural equation modelling allowed us to conclude that both OePIP1.1 and OePIP2.1 expression could explain most of the variations observed for g s and g m. CA expression also had a small but significant effect on g m in olive under water-stress conditions.


Assuntos
Aquaporinas/genética , Anidrases Carbônicas/genética , Regulação da Expressão Gênica de Plantas , Olea/genética , Olea/metabolismo , Aquaporinas/metabolismo , Anidrases Carbônicas/metabolismo , Dessecação , Olea/enzimologia , Fotossíntese , Folhas de Planta/metabolismo , Estômatos de Plantas/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
Plant Physiol Biochem ; 208: 108528, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38493662

RESUMO

Zinc (Zn) is an essential micronutrient for plants, but it is toxic beyond a certain threshold. Populus alba (L.) 'Villafranca' clone is known for its good tolerance to high Zn concentration compared to other poplar species. A line of this species overexpressing the tonoplast intrinsic aquaporin AQUA1 gene has showed an improved tolerance to Zn excess in comparison to the wild-type (wt) line. The aims of this work were to: 1) verify if AQUA1 plants can uptake Zn more efficiently after a longer period of exposure; 2) evaluate if a higher Zn uptake in transgenic lines can have negative effects; 3) assess Zn competing elements (iron and manganese), soluble sugars, osmolytes, and potassium to investigate differences in water and osmotic homeostasis between lines. Under Zn excess, AQUA1 plants showed a twofold Zn translocation factor and a higher xylem sap Zn concentration than the wt plants. Transgenic plants preferentially allocated Zn in aerial biomass and this different behaviour matched with modified manganese and iron balances suggesting that the increased Zn uptake might be related to a decrease in iron transport in the transgenic line. Moreover, a higher instantaneous water use efficiency in control conditions and an increase in bark soluble sugars under Zn excess could allow a higher resistance of AQUA1 plants to the water and osmotic perturbations caused by Zn. Indeed, the Zn excess increased the xylem osmolyte content only in wt plants. Further investigations are required to understand the role of AQUA1 in osmotic regulation.


Assuntos
Aquaporinas , Populus , Zinco/metabolismo , Populus/genética , Populus/metabolismo , Manganês , Minerais , Ferro/metabolismo , Água , Açúcares
8.
Plant Cell Rep ; 32(6): 885-98, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23553557

RESUMO

The radial growth of plant stem is based on the development of cribro-vascular cambium tissues. It affects the transport efficiency of water, mineral nutrients and photoassimilates and, ultimately, also plant height. The rate of cambial cell divisions for the assembly of new xylem and phloem tissue primordia and the rate of differentiation of the primordia into mature tissues determine the amount of biomass produced and, in the case of woody species, the wood quality. These complex physiological processes proceed at a rate which depends on several factors, acting at various levels: growth regulators, resource availability and environmental factors. Several hormonal signals and, more recently, further regulatory molecules, have been shown to be involved in the induction and maintenance of cambium and the formation of secondary vascular tissues. The control of xylem cell patterning is of particular interest, because it determines the diameter of xylem vessels, which is central to the efficiency of water and nutrient transport from roots to leaves through the stem and may strongly influence the growth in height of the tree. Increasing scientific evidence have proved the role of other hormones in cambial cell activities and the study of the hormonal signals and their crosstalking in cambial cells may foster our understanding of the dynamics of xylogenesis and of the mechanism of vessel size control along the stem. In this article, the role of the hormonal signals involved in the control of cambium and xylem development in trees and their crosstalking are reviewed.


Assuntos
Câmbio/fisiologia , Lactonas/metabolismo , Caules de Planta/fisiologia , Poliaminas/metabolismo , Árvores/fisiologia , Xilema/fisiologia , Padronização Corporal , Câmbio/citologia , Câmbio/crescimento & desenvolvimento , Diferenciação Celular , Hormônios Peptídicos/metabolismo , Caules de Planta/citologia , Caules de Planta/crescimento & desenvolvimento , Árvores/citologia , Árvores/crescimento & desenvolvimento , Xilema/citologia , Xilema/crescimento & desenvolvimento
9.
Tree Physiol ; 42(5): 1029-1042, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35021227

RESUMO

Olive can be considered as moderately tolerant to salinity, with marked differences among cultivars. In the present study, two olive cultivars with different salt tolerance, 'Leccino' (sensitive) and 'Frantoio' (tolerant), were treated with 120 mM of NaCl for 30 days. We measured the expression of genes involved in the management of sodium in the leaves, such as NHX, SOS1 and H+ ATPase, and the concentration of Na+, K+, Mn2+, Mg2+ and Ca2+ in the roots, bark, xylem and leaves of the olive plants. The results were analyzed with multiple linear models and mixed models. Furthermore, we utilized the analysis of covariance to find significant relationships in our data. Both cultivars significantly reduced net photosynthesis and increased water-use efficiency after 30 days of treatment. Sodium accumulated significantly in the roots of both cultivars, and 'Leccino' plants were also able to translocate it to the leaves and the bark. The NHX and vacuolar ATPase subunit E genes were significantly overexpressed in both the cultivars treated with NaCl. The SOS1, ATPase11 and ATPase8 genes were overexpressed in 'Frantoio'. The covariance between gene expression and element concentrations data was analyzed to identify significant interactions between cultivars and treatments. Na+ accumulation in the roots of 'Frantoio' was positively related to the accumulation of K+, Mn2+, Mg2+ and Ca2+ in the xylem, bark and leaves. 'Frantoio' capability to mobilize elements, especially Ca2+, together with the overexpression of key genes for sodium management, could be crucial for salt tolerance.


Assuntos
Olea , Tolerância ao Sal , Cálcio , Modelos Lineares , Magnésio , Olea/genética , Olea/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Salinidade , Tolerância ao Sal/genética , Sódio/metabolismo , Cloreto de Sódio
10.
Antioxidants (Basel) ; 11(4)2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35453379

RESUMO

The impact of dried apples (Malus × domestica Borkh.) addition on improving the antioxidant characteristics of dark chocolate was evaluated. The antioxidant activity was measured through DPPH scavenging activity and showed an increase in the cocoa bar with 'Nesta' dry apple (17.3% vs. 46.8%) in comparison to cocoa mass. The 15 polyphenols analyzed by UHPLC-ESI-MS/MS indicated great variability among the apple varieties. Quercetin was detected in the highest concentrations (ranged from 753.3 to 1915.5 µg g-1), while the lowest were for kaempferol 7-O-glucoside, measured only in 'Mora' and 'Nesta' cocoa bars (from 0.034 to 0.069 µg g-1, respectively). P-coumaric acid, trans-ferulic acid, and chlorogenic acid contribute largely to the antioxidant activity in cocoa bars. Principal component analysis shows that a cocoa bar with the addition of 'Nesta' dry apple differ from others due to its higher content of polyphenols (1614 ± 61.8 mg gallic acid equivalents per 100 g). In conclusion, data confirm that cocoa bars with dry apples might be considered as a polyphenol-enriched food.

11.
Environ Sci Pollut Res Int ; 28(13): 16323-16333, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33387308

RESUMO

The plant association of Populus alba L. 'Villafranca', Brassica oleracea var. acephala sebellica (kale), and B. oleracea var. capitata 'sonsma' (cabbage) was exposed to Zn, Cd, and exogenous caffeine (13CFN)-contaminated water under growth chamber conditions. In the short term of treatment (15 days), poplar increased the root dry biomass (+ 25%) and decreased the chlorophyll content in new leaves (- 32%), compared to control. On the contrary, cabbage decreased the root dry biomass, enhancing the shoot dry biomass (+ 50%). Heavy metals were mainly concentrated in plant roots and in poplar reached the highest concentrations of 705 ± 232.6 and 338 ± 85.5 µg g-1 DW for Zn and Cd, respectively. The ability of poplar to accumulate more Zn and Cd than kale and cabbage in plant biomass was confirmed by heavy metal contents, following the order: poplar > kale = cabbage. However, poplar and Brassica sp. association was very useful for Zn and Cd decontaminations as reported by the bioconcentration factors (> 1). The concentration of 13CFN was below 2.4 ng g-1 FW in poplar and 7.4 ng g-1 FW in Brassica species, suggesting the caffeine uptake and degradation by plant association. Under our experimental conditions, the removal efficiency of the system was upper to 79%, indicating the capability of Populus-Brassica association to efficiently remove Zn, Cd, and 13CFN from mixed inorganic-organic-contaminated water in short term.


Assuntos
Brassica , Metais Pesados , Populus , Poluentes do Solo , Folhas de Planta/química , Poluentes do Solo/análise , Água
12.
Antioxidants (Basel) ; 10(12)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34942968

RESUMO

Fig trees are often grown in areas affected by salinity problems. We investigated changes in the concentrations of 15 phenolic compounds and mineral elements (Mg, Ca, K, Zn, Cu, Mn, Mo, Fe, Na) in fruits of fig plants (Ficus carica L. cv. Dottato) subjected to irrigation with saline water (100 mM of NaCl) for 28 days. We used UHPLC-MS/MS techniques to determine chlorogenic acid, tiliroside, catechin, epicatechin (ECTC), p-coumaric acid, trans-ferulic acid, phloridzin, phloretine, quercetagetin 7-O-glucoside, rutin, quercetin 3-O-glucoside, kaempferol 3-O-rutinoside, kaempferol 7-O-glucoside, kaempferol 3-O-glucoside, and quercetin. There was a steep gradient of Na+ concentrations between the root and the canopy of salinized plants, but leaf Na+ was similar in control and salt-treated plants. Quercetin, ECTC, and chlorogenic acid were the most abundant phenolic compounds in fig fruits. Salinity increased total phenols by 5.6%, but this increase was significant only for ECTC. Salt stress significantly increased Zn and Mg concentration in the fruit. Leaf levels of K, Mg, Ca, and Mn were similar in control and salinized plants. Moderate salt stress appears to improve fig fruit quality because of its positive effect on nutrients and antioxidant compounds such as epicatechin.

13.
Front Plant Sci ; 12: 751959, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34868139

RESUMO

Three different cDNA sequences, designated OepPDAT1-1, OepPDAT1-2, and OepPDAT2, encoding three phospholipid:diacylglycerol acyltransferases (PDAT) have been isolated from olive (Olea europaea cv. Picual). Sequence analysis showed the distinctive features typical of the PDAT family and together with phylogenetic analysis indicated that they encode PDAT. Gene expression analysis in different olive tissues showed that transcript levels of these three PDAT genes are spatially and temporally regulated and suggested that, in addition to acyl-CoA:diacylglycerol acyltransferase, OePDAT1-1 may contribute to the biosynthesis of triacylglycerols in the seed, whereas OePDAT1-2 could be involved in the triacylglycerols content in the mesocarp and, therefore, in the olive oil. The relative contribution of PDAT and acyl-CoA:diacylglycerol acyltransferase enzymes to the triacylglycerols content in olive appears to be tissue-dependent. Furthermore, water regime, temperature, light, and wounding regulate PDAT genes at transcriptional level in the olive fruit mesocarp, indicating that PDAT could be involved in the response to abiotic stresses. Altogether, this study represents an advance in our knowledge on the regulation of oil accumulation in oil fruit.

14.
Food Chem ; 342: 128369, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33143966

RESUMO

High vacuum technology has been incorporated into a new assisted extraction system applied to virgin olive oil (VOO) processing, which was tested at a lab-scale pilot plant to evaluate its impact on the physicochemical properties of the olive paste and oil. The vacuum system induced changes in the mechanical and structural properties of the olive cells, improving the coalescence of the oil droplets due to substantial cellular and intracellular mass transfer during the process, as shown by cryo-scanning electron microscopy (Cryo-SEM) analysis. The effects on the quality characteristics of VOOs extracted from three cultivars at different malaxation temperatures were evaluated. A significant increase in the phenolic content, from 25.2% to 48.6%, was observed. The content of volatile compounds responsible for the VOO flavor decreased as a function of malaxation temperature. The reduction of some volatile molecules related to the VOO off-flavor (ethanol, ethyl acetate and acetic acid) was also shown.


Assuntos
Manipulação de Alimentos/métodos , Azeite de Oliva/química , Fenóis/análise , Compostos Orgânicos Voláteis/análise , Microscopia Crioeletrônica , Cromatografia Gasosa-Espectrometria de Massas , Olea/química , Olea/metabolismo , Fenóis/isolamento & purificação , Temperatura , Vácuo , Compostos Orgânicos Voláteis/isolamento & purificação
15.
Antioxidants (Basel) ; 9(12)2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33302468

RESUMO

Several spectroscopic techniques have been optimized to check extra-virgin olive oil quality and authenticity, as well as to detect eventual adulterations. These methods are usually complementary and can give information about different olive oil chemical components with bioactive and antioxidant properties. In the present work, a well-characterized set of extra-virgin olive oil (cultivar Frantoio) samples from a specific area of Tuscany (Italy) were investigated by combining near UV-Vis absorption spectroscopy, 1H and 13C nuclear magnetic resonance (NMR) to identify and quantify different chemical components, such as pigments, secoiridoids and squalene, related to the nutritional and quality properties of olive oils. Moreover, the pigmentation index of olives, organoleptic and sensory properties, total phenolic compound contents and the lipidic fractions of olive oils were investigated. The results obtained are, finally, compared and discussed in order to correlate several properties of both olives and olive oils with specific features of the cultivation area.

16.
Plants (Basel) ; 10(1)2020 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-33383680

RESUMO

Populus alba 'Villafranca' clone is well-known for its tolerance to cadmium (Cd). To determine the mechanisms of Cd tolerance of this species, wild-type (wt) plants were compared with transgenic plants over-expressing an aquaporin (aqua1, GenBank GQ918138). Plants were maintained in hydroponic conditions with Hoagland's solution and treated with 10 µM of Cd, renewed every 5 d. The transcription levels of heavy metal transporter genes (PaHMA2, PaNRAMP1.3, PaNRAMP2, PaNRAMP3.1, PaNRAMP3.2, PaABCC9, and PaABCC13) were analyzed at 1, 7, and 60 d of treatment. Cd application did not induce visible toxicity symptoms in wt and aqua1 plants even after 2 months of treatment confirming the high tolerance of this poplar species to Cd. Most of the analyzed genes showed in wt plants a quick response in transcription at 1 d of treatment and an adaptation at 60 d. On the contrary, a lower transcriptional response was observed in aqua1 plants in concomitance with a higher Cd concentration in medial leaves. Moreover, PaHMA2 showed at 1 d an opposite trend within organs since it was up-regulated in root and stem of wt plants and in leaves of aqua1 plants. In summary, aqua1 overexpression in poplar improved Cd translocation suggesting a lower Cd sensitivity of aqua1 plants. This different response might be due to a different transcription of PaNRAMP3 genes that were more transcribed in wt line because of the importance of this gene in Cd compartmentalization.

17.
Plant Physiol Biochem ; 146: 13-22, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31710921

RESUMO

Drought events impair the carbon and water balances in plants. Climate changes highlight the importance to understand the limits of woody species to reallocate carbon in different processes and the mechanisms driving the osmotic adjustments during the day under stress. In this frame, the aim of this work was to investigate the plant capability to shift energy among competing sinks and preserve the osmotic balance during the day under severe short periods of water deficit. The role of carbohydrates as osmolytes as well as energy sources was investigated in poplar plants. Results highlighted that during water deficit soluble sugars, derived both from the new synthetised carbon and starch degradation, were principally convoyed in the bark. This increase in carbohydrates allowed the maintenance of a water reserve used during the day to prevent a water decrease within the xylem. The decrease of xylem sap osmotic potential during the night, driven by an increase of K, Ca, and fructose (+0.46, 0.52, and 0.26 mg ml-1 in water limited plants after 8 days of withholding water, respectively), probably further attracted water into the xylem. This response mechanism increased at higher water deficit intensity. The little variations in carbohydrates and mineral elements within the leaves highlighted the main role of sinks rather than sources in the early response to water deficit.


Assuntos
Desidratação , Populus , Secas , Humanos , Osmose , Folhas de Planta , Água , Xilema
18.
BMC Plant Biol ; 9: 128, 2009 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-19852839

RESUMO

BACKGROUND: Olea europaea L. is a traditional tree crop of the Mediterranean basin with a worldwide economical high impact. Differently from other fruit tree species, little is known about the physiological and molecular basis of the olive fruit development and a few sequences of genes and gene products are available for olive in public databases. This study deals with the identification of large sets of differentially expressed genes in developing olive fruits and the subsequent computational annotation by means of different software. RESULTS: mRNA from fruits of the cv. Leccino sampled at three different stages [i.e., initial fruit set (stage 1), completed pit hardening (stage 2) and veraison (stage 3)] was used for the identification of differentially expressed genes putatively involved in main processes along fruit development. Four subtractive hybridization libraries were constructed: forward and reverse between stage 1 and 2 (libraries A and B), and 2 and 3 (libraries C and D). All sequenced clones (1,132 in total) were analyzed through BlastX against non-redundant NCBI databases and about 60% of them showed similarity to known proteins. A total of 89 out of 642 differentially expressed unique sequences was further investigated by Real-Time PCR, showing a validation of the SSH results as high as 69%. Library-specific cDNA repertories were annotated according to the three main vocabularies of the gene ontology (GO): cellular component, biological process and molecular function. BlastX analysis, GO terms mapping and annotation analysis were performed using the Blast2GO software, a research tool designed with the main purpose of enabling GO based data mining on sequence sets for which no GO annotation is yet available. Bioinformatic analysis pointed out a significantly different distribution of the annotated sequences for each GO category, when comparing the three fruit developmental stages. The olive fruit-specific transcriptome dataset was used to query all known KEGG (Kyoto Encyclopaedia of Genes and Genomes) metabolic pathways for characterizing and positioning retrieved EST records. The integration of the olive sequence datasets within the MapMan platform for microarray analysis allowed the identification of specific biosynthetic pathways useful for the definition of key functional categories in time course analyses for gene groups. CONCLUSION: The bioinformatic annotation of all gene sequences was useful to shed light on metabolic pathways and transcriptional aspects related to carbohydrates, fatty acids, secondary metabolites, transcription factors and hormones as well as response to biotic and abiotic stresses throughout olive drupe development. These results represent a first step toward both functional genomics and systems biology research for understanding the gene functions and regulatory networks in olive fruit growth and ripening.


Assuntos
Frutas/genética , Perfilação da Expressão Gênica , Olea/genética , Análise por Conglomerados , Biologia Computacional , DNA de Plantas/genética , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Redes Reguladoras de Genes , Genes de Plantas , Redes e Vias Metabólicas/genética , Análise de Sequência de DNA
19.
Environ Sci Pollut Res Int ; 26(25): 25564-25572, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31267403

RESUMO

Phthalates are micro-pollutants of great concern due to their negative effects on ecosystem functioning and human health. Thanks to its capability in uptake and accumulation of organic pollutants, Populus alba L. "Villafranca" clone could be a good candidate for reducing the impacts derived by the persistence of such compounds in the environment. We investigated plant response and uptake of dioctyl phthalate (DOP) by poplar, grown in hydroponics condition, for 21 days with 0, 40, and 400 µg L-1 of d4-DOP. Treated plants, after 21 days of 400 µg L-1 d4-DOP, showed an increase in root dry biomass (+ 29%) at the expense of aerial parts (- 8%) compared with control. The root development could be sustained by the increase of Mg uptake by poplar. LC-MS/MS analysis demonstrated the uptake and accumulation in roots of d4-DOP starting from day one (3.5 ± 3.29 and 7.1 ± 3.28 in 40 and 400 µg L-1 d4-DOP respectively), despite volatilization of d4-DOP was observed from nutritive solution. The chemical interaction between d4-DOP and Zn occurred in roots of plants treated with the high d4-DOP concentration, without limiting the Zn concentration in leaves. Results confirm the high tolerance of "Villafranca" clone to xenobiotic and suggest the poplar capability in d4-DOP uptake and accumulation at root level.


Assuntos
Dietilexilftalato/química , Populus/efeitos dos fármacos , Biodegradação Ambiental , Transporte Biológico , Biomassa , Cromatografia Líquida , Dietilexilftalato/metabolismo , Ecossistema , Hidroponia , Folhas de Planta , Raízes de Plantas , Populus/metabolismo , Espectrometria de Massas em Tandem , Poluição da Água
20.
Plant Physiol Biochem ; 141: 423-430, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31233983

RESUMO

The effect of salinity on physiological traits, fatty acid composition and desaturase genes expression in fruit mesocarp of olive cultivar Leccino was investigated. Significant reduction of shoot elongation (-12%) during salt treatments (80 mM NaCl) was associated with the translocation of Na in the aerial part. After 75 days of treatment, fruits from each plant were subdivided into four maturation groups (MG0, MG1, MG2, MG3) according to ripening degrees. Na accumulation increased in each MG under salinity, reaching the highest values in MG1 fruits (2654 mg kg-1 DW). Salinity caused an acceleration of the ripening process, increased fruit number and decreased total fatty acids content in MG3. An increase in oleic acid at MG1 (53%) was detected, with consequent increase in the oleic/linoleic (41%) and decrease in the polyunsaturated/monounsaturated ratios (30%). Those variations could be explained by the synergic up-regulation of OeSAD1, together with the down-regulation of OeFAD6 transcript levels.


Assuntos
Ácidos Graxos Dessaturases/genética , Ácidos Graxos/química , Frutas/enzimologia , Olea/enzimologia , Sais/química , Irrigação Agrícola , Expressão Gênica , Ácido Linoleico/química , Ácido Oleico/química , Fenótipo , Fotossíntese , Óleos de Plantas/química , Sódio/química , Regulação para Cima
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