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1.
Plant Dis ; 103(12): 3057-3064, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31596694

RESUMO

A number of fir species (Abies) are produced as Christmas trees around the world. In particular, Fraser fir (Abies fraseri (Pursh) Poir.) is popular as it yields high-quality Christmas trees in temperate North America and Europe. A Phytophthora sp. causing root rot on Fraser fir was isolated from a Christmas tree farm in Connecticut, U.S.A., and found to be new to science according to morphological and molecular phylogenetic analysis using multilocus DNA sequences from ITS, Cox1, ß-Tub, Nadh1, and Hsp90 loci. Thus, it was described and illustrated as Phytophthora abietivora. An informative Koch's postulates test revealed that P. abietivora was the pathogen causing root rot of Fraser fir.


Assuntos
Abies , Filogenia , Phytophthora , Abies/parasitologia , Connecticut , DNA de Protozoário/genética , Phytophthora/classificação , Especificidade da Espécie
2.
Sci Total Environ ; 690: 1254-1267, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31470488

RESUMO

Drought-induced forest dieback is causing reductions in productivity, increasing tree mortality and impairing terrestrial carbon uptake worldwide. However, the role played by long-term nutrient imbalances during drought-induced dieback is still unknown. To improve our knowledge on the relationships between dieback and nutrient imbalances, we analysed wood anatomical traits (tree-ring width and wood density), soil properties and long-term chemical information in tree-ring wood (1900-2010) by non-destructive Micro X-ray fluorescence (µXRF) and destructive (ICP-OES) techniques. We studied two major European conifers with ongoing drought-induced dieback in mesic (Abies alba, silver fir) and xeric (Pinus sylvestris, Scots pine) sites. In each site we compared coexisting declining (D) and non-declining (ND) trees. We used dendrochronology and generalized additive and linear mixed models to analyse trends in tree-ring nutrients and their relationships with wood traits. The D trees presented lower growth and higher minimum wood density than ND trees, corresponding to a smaller lumen area of earlywood tracheids and thus a lower theoretical hydraulic conductivity. These differences in growth and wood-anatomy were more marked in silver fir than in Scots pine. Moreover, most of the chemical elements showed higher concentrations in D than in ND trees during the last two-five decades (e.g., Mn, K and Mg), while Ca and Na increased in the sapwood of ND trees. The Mn concentrations, and related ratios (Ca:Mn, Mn:Al and P:Mn) showed the highest differences between D and ND trees for both tree species. These findings suggest that a reduced hydraulic conductivity, consistent with hydraulic impairment, is affecting the use of P in D trees, making them more prone to drought-induced damage. The retrospective quantifications of Mn ratios may be used as early-warning signals of impending dieback.


Assuntos
Secas , Monitoramento Ambiental , Florestas , Abies , Clima , Nitrogênio , Fósforo , Pinus sylvestris , Árvores
3.
Int J Biometeorol ; 63(12): 1631-1640, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31385094

RESUMO

There is evidence that the ongoing climate change is happening through nighttime rather than daytime warming. How such a daily-asymmetric warming modifies plant phenology is still unclear. We investigated the effects of asymmetric warming on bud break by daily monitoring seedlings belonging to 26 black spruce [Picea mariana (Mill.) BSP.] and 15 balsam fir [Abies balsamea (L.) Mill.] provenances from the native range in Canada. Seedlings were subjected to either daytime or nighttime warming in three growth chambers at temperatures ranging between 10 and 24 °C. On average, a warming of 4 °C advanced the timings of bud break in both species by 2.4 days, with the later phases being more sensitive to the treatment. Bud break of both species responded more strongly to daytime warming, with the bud break occurred 1.2 and 3.2 days earlier under daytime than nighttime warming in black spruce and balsam fir, respectively. A marked ecotypic differentiation was only observed in black spruce that originated from provenances distributed broadly across Canada, with seedlings from the warmest provenance completing bud break 8.3 days later than those from the coldest one. However, no significant effect of provenance was observed for balsam fir, the narrowly distributed species. Overall, the above results suggest that a higher temporal resolution such as temperatures during daytime and nighttime, and higher spatial resolution should be taken into account to improve the accuracy of phenological model predictions under global change scenarios. Phenological models based on daily average temperature should take into account the diverging impacts of asymmetric warming on plant phenology. Our findings may indicate that the influence of warming on plant phenology may be less dramatic than expected.


Assuntos
Abies , Picea , Canadá , Mudança Climática , Estações do Ano , Plântula , Temperatura Ambiente
4.
J Microbiol ; 57(11): 953-958, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31463785

RESUMO

A strictly aerobic, motile, endospore-forming, rod-shaped bacterium, designated HS21T, was isolated from rhizospheric soil of the Korean fir tree (Abies koreana) from Halla mountain on Jeju island, Korea. Growth of strain HS21T was observed at pH 6.0-8.0 (optimum: pH 7.0), 0-2% (w/v) NaCl and 4-30°C (optimum: 25°C). A comparative analysis of 16S rRNA gene sequences showed that strain HS21T was most closely related to Cohnella luojiensis HY-22RT (97.6%), followed by C. lupini RLAHU4BT (97.4%) and C. collisoli NKM-5T (97.2%). The genome of strain HS21T comprised a circular chromosome of 7,059,027 bp with 44.8% G + C content. The DNA-DNA relatedness values between strain HS21T and C. luojiensis HY-22RT and C. lupini RLAHU4BT were 18.1% and 13.8%, respectively. The major cellular fatty acids (> 5%) of the isolate were anteiso-C15:0, iso-C16:0, C16:0, and iso-C15:0. The polar lipids present were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, lysylphosphatidylglycerol, and three unidentified aminophospholipids. Based on its phenotypic, phylogenetic, genomic, and chemotaxonomic properties, strain HS21T represents a novel species of the genus Cohnella, for which the name Cohnella abietis sp. nov. is proposed. The type strain is HS21T (= KCTC 43028T = CCTCC AB 2019010T).


Assuntos
Abies/microbiologia , Bacillales/classificação , Bacillales/isolamento & purificação , Filogenia , Rizosfera , Microbiologia do Solo , Bacillales/genética , Bacillales/fisiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Lipídeos/química , Lisina/química , Fosfatidilgliceróis/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Nódulos Radiculares de Plantas/microbiologia , Análise de Sequência de DNA , Solo , Sequenciamento Completo do Genoma
5.
Oecologia ; 191(3): 483-491, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31456021

RESUMO

Leaf longevity (LL), the amount of time a photosynthetically active leaf remains on a plant, is an important trait of evergreen species, affecting physiological ecology and ecosystem processes. A long LL gives leaves more time to fix carbon but carries higher construction costs, while a short LL allows plants to respond more rapidly to changing environmental conditions. For many evergreen taxa, LL data are not readily available, and it is not known if LL is phylogenetically conserved. To address this gap, we measured LL for 169 temperate and boreal evergreen woody species at the Arnold Arboretum, a botanical garden in Boston, Massachusetts, along with metrics of leaf size and number known to be related to LL. We hypothesized that LL is phylogenetically conserved, and that longer LL is associated with a greater numbers of leaves, smaller leaves, and a colder hardiness zone of the species' native range. We found that average LL ranged from 1.4 years in Rhododendron tomentosum to 10.5 years in Abies cilicia. LL was phylogenetically conserved, with some genera, such as Abies and Picea, exhibiting long LL (> 3 years) and others, such as Ilex and Rhododendron, exhibiting short LL (< 3 years). Leaf length was negatively correlated with LL in conifers, due to differences between Pinus and other genera; however, there was no correlation between LL and number of leaves. This study highlights the considerable variation and phylogenetic pattern in LL among temperate evergreen species, which has implications for carbon budgets and ecosystem models.


Assuntos
Abies , Pinus , Ecossistema , Filogenia , Folhas de Planta
6.
Environ Pollut ; 253: 646-654, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31330356

RESUMO

Although plants are often exposed to atmospheric nanoparticles (NPs), the mechanism of NP deposition and their effects on physiology and metabolism, and particularly in combination with other stressors, are not yet understood. Exploring interactions between stressors is particularly important for understanding plant responses in urban environments where elevated temperatures can be associated with air pollution. Accordingly, 3-year-old spruce seedlings were exposed for 2 weeks to aerial cadmium oxide (CdO) NPs of environmentally relevant size (8-62 nm) and concentration (2 × 105 cm-3). While half the seedlings were initially acclimated to high temperature (35 °C) and vapour pressure deficit (VPD; 2.81 kPa), the second half of the plants were left under non-stressed conditions (20 °C, 0.58 kPa). Atomic absorption spectrometry was used to determine Cd content in needles, while gas and liquid chromatography was used to determine changes in primary and secondary metabolites. Photosynthesis-related processes were explored with gas-exchange and chlorophyll fluorescence systems. Our work supports the hypothesis that atmospheric CdO NPs penetrate into leaves but high temperature and VPD reduce such penetration due to stomatal closure. The hypothesis that atmospheric CdO NPs influences physiological and metabolic processes in plants was also confirmed. This impact strengthens with increasing time of exposure. Finally, we found evidence that plants acclimated to stress conditions have different sensitivity to CdO NPs compared to plants not so acclimated. These findings have important consequences for understanding impacts of global warming on plants and indicates that although the effects of elevated temperatures can be deleterious, this may limit other forms of plant stress associated with air pollution.


Assuntos
Poluentes Atmosféricos/toxicidade , Compostos de Cádmio/toxicidade , Nanopartículas/toxicidade , Óxidos/toxicidade , Picea/efeitos dos fármacos , Temperatura Ambiente , Abies , Aclimatação/fisiologia , Poluentes Ambientais/metabolismo , Aquecimento Global , Temperatura Alta , Fotossíntese/fisiologia , Picea/fisiologia , Pinus , Folhas de Planta/efeitos dos fármacos , Plântula/efeitos dos fármacos
7.
G3 (Bethesda) ; 9(7): 2039-2049, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31217262

RESUMO

Silver fir (Abies alba Mill.) is a keystone conifer of European montane forest ecosystems that has experienced large fluctuations in population size during during the Quaternary and, more recently, due to land-use change. To forecast the species' future distribution and survival, it is important to investigate the genetic basis of adaptation to environmental change, notably to extreme events. For this purpose, we here provide a first draft genome assembly and annotation of the silver fir genome, established through a community-based initiative. DNA obtained from haploid megagametophyte and diploid needle tissue was used to construct and sequence Illumina paired-end and mate-pair libraries, respectively, to high depth. The assembled A. alba genome sequence accounted for over 37 million scaffolds corresponding to 18.16 Gb, with a scaffold N50 of 14,051 bp. Despite the fragmented nature of the assembly, a total of 50,757 full-length genes were functionally annotated in the nuclear genome. The chloroplast genome was also assembled into a single scaffold (120,908 bp) that shows a high collinearity with both the A. koreana and A. sibirica complete chloroplast genomes. This first genome assembly of silver fir is an important genomic resource that is now publicly available in support of a new generation of research. By genome-enabling this important conifer, this resource will open the gate for new research and more precise genetic monitoring of European silver fir forests.


Assuntos
Abies/genética , Genoma de Planta , Genômica , Biologia Computacional/métodos , Bases de Dados Genéticas , Tamanho do Genoma , Genoma de Cloroplastos , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Anotação de Sequência Molecular , Sequenciamento Completo do Genoma
8.
Fungal Biol ; 123(6): 456-464, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31126422

RESUMO

We compared the δ13C and δ15N of forest material with an extensive sporocarp collection to elucidate the role of litter, wood and soil as fungal carbon and nitrogen sources in Finnish boreal Picea abies-dominated forests. Ectomycorrhizal Hydnum and Cortinarius had higher δ15N than other ectomycorrhizal fungi, suggesting use of 15N-enriched, deeper nitrogen. Russula had lower δ15N than other ectomycorrhizal fungi and resembled some litter decay genera, suggesting use of litter-derived nitrogen. There was little variation in δ15N among other genera of ectomycorrhizal fungi, indicating limited functional diversity in nitrogen use. Saprotrophic Leotia, Gymnopus, Hypholoma, Pholiota, Rhodocollybia and Calocera had δ15N values similar to ectomycorrhizal fungi, indicating overlap in use of older nitrogen from soil or roots or use of newly fixed nitrogen. Genera of litter and wood decay fungi varied up to 6‰ in δ13C and 10‰ in δ15N, suggesting large differences in carbon and nitrogen sources and processing. Similar δ13C between white and brown rot wood decay fungi also suggest that white rot fungi do not use lignin-derived carbon. Together, these δ13C and δ15N patterns of fungi from Finnish boreal forests enhance our knowledge of fungal functional diversity and indicate broad use of litter, wood and soil resources.


Assuntos
Carbono/metabolismo , Fungos/metabolismo , Micorrizas/metabolismo , Nitrogênio/metabolismo , Abies , Basidiomycota/metabolismo , Finlândia , Taiga , Madeira/microbiologia
9.
J Agric Food Chem ; 67(23): 6523-6531, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31117507

RESUMO

Identification of diterpene synthase-encoding genes together with synthetic biology technology offers an opportunity for the biosynthesis of cis-abienol. The methylerythritol phosphate (MEP) and the mevalonate (MVA) pathways were both engineered for cis-abienol production in Escherichia coli, which improved the cis-abienol yield by approximately 7-fold and 31-fold, respectively, compared to the yield obtained by overexpression of the MEP pathway alone or the original MEP pathway. Furthermore, systematic optimization of cis-abienol biosynthesis was performed, such as diterpene synthase screening and two-phase cultivation. The combination of bifunctional class I/II cis-abienol synthase from Abies balsamea ( AbCAS) and class II abienol synthase from Salvia sclarea ( SsTPS2) was found to be the most effective. By using isopropyl myristate as a solvent in two-phase cultivation, cis-abienol production reached 634.7 mg/L in a fed-batch bioreactor. This work shows the possibility of E. coli utilizing glucose as a carbon source for cis-abienol biosynthesis through a modified pathway.


Assuntos
Diterpenos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Engenharia Metabólica , Ácido Mevalônico/metabolismo , Naftóis/metabolismo , Abies/enzimologia , Vias Biossintéticas , Diterpenos/química , Fermentação , Glucose/metabolismo , Naftóis/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Salvia/enzimologia
10.
Int J Biometeorol ; 63(7): 963-972, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30903292

RESUMO

Impacts of climatic means on spring phenology are well documented, whereas the role of climatic variance, such as occurrence of spring frosts, has long been neglected. A large elevational gradient of forests on the southeastern Tibetan Plateau provides an ideal platform to explore correlates of spring phenology and environmental factors. We tested the hypothesis that spring frost was a major factor regulating the timing of bud-leaf phenology by combining 5 years of in situ phenological observations of Abies georgei var. smithii with concurrent air temperature data along two altitudinal gradients. Mean lapse rate for the onset of bud swelling and leaf unfolding was 3.1 ± 0.5 days/100 m and 3.0 ± 0.6 days/100 m, respectively. Random forest analysis and conditional inference trees revealed that the frequency of freezing events was a critical factor in determining the timing of bud swelling, independent of topographic differences, varying accumulation of chilling days, and degree-days. In contrast, the onset of leaf unfolding was primarily controlled by the bud swelling onset. Thus, the timing of bud swelling and leaf unfolding appear to be controlled directly and indirectly, respectively, by spring frost. Using space-for-time substitution, the frequency of spring freezing events decreased by 7.1 days with 1 °C of warming. This study provides evidence for impacts of late spring frosts on spring phenology, which have been underappreciated in research on phenological sensitivity to climate but should be included in phenology models. Fewer spring freezing events with warming have important implications for the upward migration of alpine forests and treelines.


Assuntos
Abies , Árvores , Estações do Ano , Temperatura Ambiente , Tibet
11.
Food Funct ; 10(4): 2030-2039, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30907398

RESUMO

Resveratrol exists widely in plant species and has a variety of anti-oxidant, anti-inflammatory, and immunomodulatory properties. However, there have been few reports regarding its anti-food allergic activity. In this study, we demonstrated that resveratrol (isolated from Abies georgei) could decrease the release of ß-hexosaminidase and histamine in rat basophilic leukemia-2H3 cells. Resveratrol was not only found to suppress the development of diarrhea, up-regulate the rectal temperature of ovalbumin-allergic mice, and decrease the serum level of specific immunoglobulin E, mouse mast cell protease-1 and histamine, but also found to decrease the population of dendritic cells, B cells and mast cells of ovalbumin -allergic mice in the spleen or mesenteric lymph node. Furthermore, resveratrol inhibited the release of ß-hexosaminidase and histamine in bone marrow-derived cells and alleviated mast cell-mediated passive cutaneous anaphylaxis reactions. These findings indicated that resveratrol isolated from Abies georgei might have the potential to alleviate food hypersensitivity or allergic disease.


Assuntos
Abies/química , Antialérgicos/administração & dosagem , Hipersensibilidade Alimentar/tratamento farmacológico , Mastócitos/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Resveratrol/administração & dosagem , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Linhagem Celular , Modelos Animais de Doenças , Feminino , Hipersensibilidade Alimentar/etiologia , Hipersensibilidade Alimentar/imunologia , Histamina/imunologia , Humanos , Imunoglobulina E/imunologia , Mastócitos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/efeitos adversos , Anafilaxia Cutânea Passiva/efeitos dos fármacos , Peptídeo Hidrolases/imunologia , Ratos , beta-N-Acetil-Hexosaminidases/imunologia
12.
Ying Yong Sheng Tai Xue Bao ; 30(3): 805-813, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30912372

RESUMO

Mean sensitivity (MS) of tree ring is a key index representing the sensitivity of tree rings to climate. Understanding the variation of MS and its influencing factors at a large area is helpful to understand the interaction between tree growth and climate. We used 573 tree-ring width chronologies in Asia from the International Tree Ring Date Bank (ITRDB) to examine the variation of tree-ring sensitivity and potential influencing factors. The results showed that the MS of trees was high in the arid regions and cold regions. Precipitation was more important than temperature in diriving MS. Consistent with the pattern of up-down-up for precipitation, MS showed a down-up-down fluctuation with increasing altitude, indicating that precipitation affected by altitude was a key climate factor for the MS. MS had great difference due to different physiological traits among tree species. Light-adapted species, such as Juniperus przewalskii and Pinus gerardiana, had high MS due to drought tole-rance. Shade-adapted species, such as Picea and Abies, had low MS. Old trees may have high MS.


Assuntos
Árvores , Abies , Altitude , Ásia , Clima , Juniperus
13.
Artigo em Inglês | MEDLINE | ID: mdl-30795725

RESUMO

Airborne bacteria and fungi are an ongoing problem in hospitals. Because of the antimicrobial activities of essential oils (EOs) dispersion of EOs into the air may help to reduce this contamination. The aim of this study was to evaluate the efficacy of the dispersion of selected EOs in reducing the microbial contamination in two hospital wards. The study was carried out at two wards of a 1,227-bed acute-care hospital in Austria. The concentration of airborne bacteria and fungi was measured in patient rooms before and after dispersion of a mixture of Citrus limon EO and Abies alba EO. Before dispersion of the EOs in both wards the mean concentration of bacteria was in a typical range (123 colony forming units (CFU) m-3 and 104 CFU m-3) while the mean concentration of fungi differed substantially (155 CFU m-3 and 28 CFU m-3). After dispersion of the EOs, a reduction in both bacterial and fungal contamination was observed. In the first two hours the mean concentration of airborne bacteria and fungi was reduced by approximately 40% and 30%-60% respectively. The selected EO mixture is effective in reducing the microbial contamination of the indoor air.


Assuntos
Abies/química , Microbiologia do Ar/normas , Poluição do Ar em Ambientes Fechados/prevenção & controle , Citrus/química , Óleos Voláteis/farmacologia , Quartos de Pacientes/normas , Bactérias/efeitos dos fármacos , Contagem de Colônia Microbiana , Microbiologia Ambiental , Fungos/efeitos dos fármacos , Humanos , Óleos Voláteis/isolamento & purificação
14.
Artif Cells Nanomed Biotechnol ; 47(1): 512-523, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30810403

RESUMO

In recent times, Gold nanoparticles (AuNPs) synthesized from plant extracts and their anticancer activity have attracted significant attention. We report the green approach for the synthesis of AuNPs using extract from Abies spectabilis plant. In this study, the reaction parameters were optimized to control the size of the nanoparticle, which was confirmed by Transmission Electron microscopy (TEM). Various characterization technique such as SAED pattern, UV visible spectroscopy, EDX, FTIR, and AFM were employed to analyze the synthesized AuNPs obtained from A. spectabilis plant extract. Furthermore, we investigated the anticancer activities using T24 cell lines. Interestingly, the results of extensive screening on the applications of newly synthesized AuNPs were tested for their cytotoxicity effects on anticancer activity against T24 cells by MTT assay. The cell apoptosis was studied using TUNEL, DAPI, caspase activity, cell invasion and migration. Nanoparticles at different concentrations ranging from 1 to 25 µg/ml exhibited a dose dependent cytotoxicity for 24 h. Condensation and DNA fragmentation are characteristic of apoptosis by DAPI, TUNEL staining, and the significant up regulations of Beclin-1, Bax and caspase 3, whereas the expressions of anti-apoptotic Bcl-2 and Bid were down regulated. However, this study, therefore attempts to report the synthesis, characterization, and anticancer activity of gold nanoparticles of A. spectabilis plant extract beneficial for cancer therapeutics.


Assuntos
Abies/química , Antineoplásicos , Ouro , Nanopartículas Metálicas , Extratos Vegetais/química , Neoplasias da Bexiga Urinária , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Ouro/química , Ouro/farmacologia , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia
15.
Tree Physiol ; 39(5): 747-754, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30715531

RESUMO

Present-day global warming is occurring faster at higher elevations. Although there is much information regarding the divergent responses of tree growth to climate change, the altitudinal patterns of species-specific xylogenesis remains poorly understood. We investigated the xylogenesis of balsam fir (Abies balsamea Mill.) and black spruce (Picea mariana Mill. B.S.P.) at two elevations in Quebec (Canada). The number of enlarging and mature cells of the developing tree ring were counted on microcores collected weekly between 2011 and 2014. At the lower site, the growth pattern and duration of xylogenesis were similar between species. No difference in responses to temperature and solar radiation between species was observed. At the higher site, however, cell production was higher and lasted longer in balsam fir than black spruce. Furthermore, the xylem growth of balsam fir had a stronger response to temperature and solar radiation than black spruce. These findings demonstrate the contrasting strategies of wood formation of the two species, with black spruce being more conservative than balsam fir. Our study provides evidence that sympatric species can have species-specific growth dynamics and site-specific responses to the local environment. Predictions of tree growth under a changing environment require the incorporation of species-specific growth strategies.


Assuntos
Abies/crescimento & desenvolvimento , Clima , Picea/crescimento & desenvolvimento , Xilema/crescimento & desenvolvimento , Altitude , Quebeque , Temperatura Ambiente
16.
J Exp Ther Oncol ; 13(1): 23-31, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30658023

RESUMO

Objective: The potential anti-inflammatory efficacy of resin extract of Abies cilicica in glucose dependent inflammation and tumor necrosis factor alpha (TNF-a) induced inflammation models was investigated. Its effects on monocyte adhesion, gene expression levels of P-selectin, ICAM-1, VCAM1 and transendothelial migration for the two in vitro models were measured. Also, total flavonoid and total phenolic contents of the extract were determined. Objective: Monocyte adhesion tests showed that the extract increased 100% inflammatory effect of TNF-a induced inflammation. On the other hand, it did not change number of adherent monocytes in glucose dependent inflammation model. Although the extract has trigger effect on monocyte adhesion, it did not change migration of leukocytes across ECV304 cells after administration of TNFa on ECV304 cells. The number of migrated monocytes was similar with only TNFa incubation experiment results. However, it significantly decreased monocyte migration in glucose dependent inflammation model. In our both experimental inflammation model, ICAM-1 expression significantly decreased. Although it is known that triggering effect of TNF-a on ICAM-1 expression, the content of of resin extract of A. cilicica prevented this effect. Phenolic antioxidant capacity of the extract are higher than its flavonoid contents.This study provides the first evidence that the extract inhibits glucose dependent inflammation. It may serve as an anti-inflammatory agent in the treatment of chronic inflammation caused by diabetes.


Assuntos
Abies , Glucose , Inflamação , Extratos Vegetais , Abies/química , Adesão Celular , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Molécula 1 de Adesão Intercelular , Monócitos , Extratos Vegetais/farmacologia
17.
Plant Dis ; 103(3): 538-545, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30667322

RESUMO

Defining host-pathogen interactions between species of root-rotting Phytophthora and Abies in Christmas tree production areas is important for tailoring management activities on a regional scale and for developing molecular tools for identifying resistant host species. Classifying Abies species as resistant or susceptible is complicated by regional variation in abundance and aggressiveness of Phytophthora species and the influence of environment on symptom expression and host vigor. Because previous studies performed to assess host response to Phytophthora root rot (PRR) have focused on one or a few species of either the host or pathogen, a multifactorial experiment was conducted to assess the responses of seven species of Abies challenged with three isolates each of four Phytophthora species under contrasting temperature conditions. Evaluation of mortality, root rot severity, and remaining root biomass after 16 weeks of exposure to the pathogen confirmed prior inferences regarding inherent variation in the resistance responses of various species of Abies and demonstrated evidence of variation in aggressiveness among species of Phytophthora as well as different isolates of the same Phytophthora species. The ambient temperatures at which studies were conducted had a conspicuous effect on host mortality, root rot severity, and radial growth of Phytophthora. Understanding how host responses differ under variable pathogen attack and ambient environment will improve efforts to control PRR using host species substitutions on infested ground.


Assuntos
Abies , Meio Ambiente , Interações Hospedeiro-Parasita , Phytophthora , Abies/parasitologia , Phytophthora/fisiologia , Doenças das Plantas/parasitologia , Raízes de Plantas/parasitologia
18.
Tree Physiol ; 39(4): 590-605, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30597102

RESUMO

Synchrony between host budburst and insect emergence greatly influences the time window for insect development and survival. A few alterations of bud phenology have been reported under defoliation without clear consensus regarding the direction of effects, i.e., advance or delay. Here, we compared budburst phenology between conifers in defoliation and control treatments, and measured carbon allocation as a potential mechanistic explanation of changes in phenology. In a 2-year greenhouse experiment, saplings of balsam fir, black spruce and white spruce of two different provenances (north and south) were subjected to either control (no larvae) or natural defoliation treatment (larvae added) by spruce budworm. Bud and instar phenology, primary and secondary growth, defoliation and non-structural carbohydrates were studied during the growing season. No differences were observed in bud phenology during the first year of defoliation. After 1 year of defoliation, bud phenology advanced by 6-7 days in black spruce and balsam fir and by 3.5 days in white spruce compared with the control. Because of this earlier bud break, apical and shoot growth exceeded 50% of its final length before mature instar defoliation occurred, which decreased the overall level of damage. A sugar-mediated response, via earlier starch breakdown, and higher sugar availability to buds explains the advanced budburst in defoliated saplings. The advanced phenological response to defoliation was consistent across the conifer species and provenances except for one species × provenance combination. Allocation of carbon to buds and shoots growth at the expense of wood growth in the stem and reserve accumulation represents a shift in the physiological resources priorities to ensure tree survival. This advancement in bud phenology could be considered as a physiological response to defoliation based on carbohydrate needs for primary growth, rather than a resistance trait to spruce budworm.


Assuntos
Abies/fisiologia , Interações Hospedeiro-Parasita , Mariposas/fisiologia , Picea/fisiologia , Doenças das Plantas/parasitologia , Traqueófitas/fisiologia , Abies/parasitologia , Animais , Carbono/metabolismo , Larva , Fenótipo , Picea/parasitologia , Folhas de Planta/parasitologia , Folhas de Planta/fisiologia , Estações do Ano , Amido/metabolismo , Estresse Fisiológico , Traqueófitas/parasitologia , Árvores
19.
Ultrason Sonochem ; 50: 200-207, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30245204

RESUMO

This work investigated the physicochemical properties of Chinese fir after ultrasound-assisted pretreatments with borax and sodium hydroxide additives in an aqueous solution. TGA, FTIR, and XRD were used to analyze the thermal degradation processes, changes in chemical structures, and crystallinity of the treated samples, respectively. Additionally, the release of volatiles from wood pyrolysis was measured on-line by the TG-FTIR apparatus. In thermal analysis, all samples showed main degradation stages at 220-500 °C, and alkaline compounds could efficiently shift the process to lower temperatures with lower maximum weight loss rate (MWLR) and more residues. From TG-FTIR, it was observed that CO2 was the primary gas product from pyrolysis in the alkaline-treated samples, while there were more carbonyl compounds released in the control and deionized water groups. Due to the destruction and removal of hemicellulose and lignin after alkaline treatments, the related peaks changed greatly. Changes in the ester groups caused by saponification also accounted for one of the most significant differences between samples. Moreover, except for the deionized water group without sonication, the crystallinity of the samples increased from 6.34% to 11.29%. Overall, comparing the samples treated with or without ultrasound, the results showed that the ultrasound treatment did influence the samples' physicochemical properties, and its' effects varied by the basicity of the solution. This in-depth investigation offers a better understanding of ultrasound-assisted and alkaline pretreatments of wood materials.


Assuntos
Abies/química , Boratos/química , Hidróxido de Sódio/química , Ondas Ultrassônicas , China , Cristalização , Cristalografia por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
20.
Plant Foods Hum Nutr ; 74(1): 47-53, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30361961

RESUMO

The diet rich in fruits and vegetables reduces the risk of metabolic syndrome, including diabetes development by various mechanisms of action, mainly due to the presence of polyphenolic compounds. Extracts from different conifer species are known to be a rich source of various polyphenols. In the present study we elucidated the in vitro mechanism of anti-diabetic activity of silver fir (Abies alba) wood and bark extracts and compared their activity to non-coniferous sweet chestnut wood extract and standardized maritime pine bark extract. Extracts and lignans were tested for their inhibitory activity of enzymes involved in the regulation of blood glucose in vitro. The ability of extracts to protect against oxidative stress in high glucose environment was tested on mouse myoblast cell line. Silver fir wood and bark extracts were shown to be effective inhibitors of α-glucosidase, α-amylase and dipeptidyl peptidase 4, three enzymes involved in the regulation of blood glucose levels. Coniferous extracts also showed protection against oxidative stress generated in high glucose environment. Lignans, particularly pinoresinol diglucoside, isolariciresinol and secolariciresinol were shown to be important contributors of antihyperglycemic activity through inhibition of dipeptidyl peptidase 4. This corroborates previously published in vivo results on blood glucose level obtained with silver fir wood extract and supports the use of silver fir wood and bark extracts as food supplements or functional foods in borderline diabetes.


Assuntos
Abies/química , Glicemia/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Extratos Vegetais/farmacologia , alfa-Amilases/antagonistas & inibidores , Animais , Linhagem Celular , Dipeptidil Peptidase 4/metabolismo , Inibidores da Dipeptidil Peptidase IV/isolamento & purificação , Inibidores da Dipeptidil Peptidase IV/farmacologia , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/farmacologia , Humanos , Hipoglicemiantes/isolamento & purificação , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Casca de Planta/química , Extratos Vegetais/isolamento & purificação , Madeira/química , alfa-Glucosidases/metabolismo
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