703 research outputs found

    Endophytic fungal community structure in olive orchards with high and low incidence of olive anthracnose

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    Fungal endophytes have been increasingly recognized to promote host plant protection to pathogens, but knowledge of the multiple effects that they could have in crop diseases is still scarce. This work attempts to understand the role of fungal endophytes in crop diseases, specifically in reducing disease development and interfering on lifestyle transition of the pathogen. To accomplish this, the endophytic fungal community of reproductive organs of olive tree from two orchards showing different levels of anthracnose incidence, a major disease of olive fruits, was characterized and compared between them. The two orchards showed distinct endophytic communities, differing in species richness, abundance and composition, with highest isolation rates and richness of endophytes in the orchard with low anthracnose incidence. These differences among orchards were greater on fruits than on flowers, suggesting that these changes in endophytic fungal composition may influence the lifestyle shifts in pathogen (from latent to pathogen). A number of fungal taxa were found to be positively associated to one of the two orchards. The fungal endophytes best correlated with high incidence of anthracnose are pathogens, while endophytes-associated to low anthracnose incidence are described to protect plants. Altogether, the results suggest varying pathogen-endophyte interactions among the two orchards.This work is supported by FEDER funds through the COMPETE (Operational Programme for Competitiveness Factors) and by the Foundation for Science and Technology (FCT, Portugal) within the POCI-01-0145- FEDER-031133 Project (MicOlives—Exploiting plant induced resistance by beneficial fungi as a new sustainable approach to olive crop protection), and FCT/MCTES to CIMO (UIDB/00690/2020). F. Martins thanks the award of a PhD scholarship (ref. SFRH/BD/112234/2015) by FCT.info:eu-repo/semantics/publishedVersio

    Web architecture affects the functional response of the space web-builder Kochiura aulica against Trioza erytreae in the laboratory

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    The “citrus greening disease” or huanglongbing (HLB) is caused by the Gram-negative bacteria Candidatus Liberibacter spp. One vector of HLB, the African citrus psyllid Trioza erytreae (del Guercio, 1918), was recorded for the first time in 2014, in mainland Spain, and since then, it has spread throughout the Iberian Peninsula. Spiders could be natural enemies of T. erytreae. In this work, we assessed the potential of a model spider species, selected according to the most abundant guild in the field, as a natural enemy of T. erytreae. Theridiidae was the most successful family, capturing adults of T. erytreae in the field. Kochiura aulica (Theridiidae) was selected as a model for functional response assays in the laboratory. The effect of web-building plasticity on the functional response of K. aulica was investigated using two types of arena. The spiders developed tubular-like or branch-like webs according to the spatial constraints. The web architecture significantly shifted the trapping efficiency of K. aulica. Functional responses for tubular and branch webs were both Type-II, but more psyllid prey were captured and killed in the tubular webs than in branch webs. In addition, significantly more psyllids survived in branch-like webs. Our results suggest that web architecture is a key factor driving the number of captured adults of the psyllid. Space web builders could be successful natural enemies of T. erytreae, although further research is needed to clarify the influence of web-building plasticity on the functional response and trapping efficiency of spiders.The authors are grateful to the European Union grant, programme H2020 entitled: PREHLB: Preventing HLB epidemics for ensuring citrus survival in Europe. H2020-SFS-2018–2 Topic SFS-05–2018-2019–2020—new and emerging risks to plant health (Project nº 817526)—as well as to the Foundation for Science and Technology (FCT, Portugal) for financial support by national funds FCT/MCTES to CIMO (UIDB/00690/2020) and Associated Laboratory SusTEC (LA/P/0007/2020).info:eu-repo/semantics/publishedVersio

    Evaluation of the biocontrol potential of an antagonist against olive knot disease in olive trees (Olea europaea L.)

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    The olive knot, caused by the bacterium Pseudomonas savastanoi pv. savastanoi (Psv), is one of the most serious diseases affecting olive tree (Olea europaea L.) in many regions of the world and mainly in Mediterranean countries. This disease produces tumors, especially in olive tree stems and trunk, leading to the death of the plant. In recent years, the use of microbial biocontrol agents for the control of plant diseases has gained considerable attention. Previous studies have revealed that, several bacteria strains naturally occurring in the olive tree phyllosphere, exhibit capacity to inhibit in vitro growth of Psv, being the greatest antagonistic effect displayed by Bacillus En40. The aim of the present study was to evaluate the ability of this strain to suppress Psv and olive knot development in olive trees. Pot experiments were conducted with 2-year-old olive plantlets cv. Cobrançosa inoculated with the selected strain or Psv, or in combination of both. Phenotypic traits associated with plant growth (e.g. biomass yield, total shoot/root height, and photosynthetic pigments content) and biocontrol abilities (e.g. abundance of Psv and assessment of disease symptoms) were evaluated, up to 120 days after inoculation. While development and growth of Psv+antagonist-inoculated plants showed to be similar to non-inoculated plants, photosynthetic pigments contents were observed to be higher in antagonist-inoculated plants than in other treatments. When compared with Psv-inoculated plants, plants treated with the antagonist revealed a significant reduction (p<0.01) in knots formation and size. Antagonist-inoculated plants showed also a reduction of the abundance of Psv in the inoculation sites (from 22.4 to 7.5 UFC/μL, p<0.01), suggesting its capacity to reduce the patogen's growth. This strain was identified to supres Psv and disease development on olive plants and thus, it should be considered in the future as a possible biocontrol agent against olive knot disease.This work is funded by FEDER funds through COMPETE (Programa Operacional Factores de Competitividade) and by national funds by FCT (Fundação para a Ciência e a Tecnologia) in the framework of the project EXCL/AGR-PRO/0591/2012. D. MINA thanks thinfo:eu-repo/semantics/publishedVersio

    Biological control of Pseudomonas savastanoi pv. savastanoi by two bacterial isolated from olive tree phyllosphere

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    Olive knot disease, caused by the bacterium Pseudomonas savastanoi pv. savastanoi (Psv), has been responsible for high economical crop losses in olive orchards, especially in Mediterranean countries. Olive knot cannot be eradicated once it is established in an orchard, and therefore its control is based on preventive measures. Laboratory experiments previously performed by us have showed the capacity of some bacterial species, isolated from olive tree phyllosphere, to inhibited Psv growth. In the present work, the two most promising bacterial isolates (i.e. Frondihabitans sp. and Paenibacillus sp.) were evaluated for the control of Psv in olive plantlets (Olea europaea L.) under greenhouse conditions, to predict their effect in a more natural condition. In pot experiments, two-year-old olive plants cv. Cobrançosa were inoculated with the antagonistic bacteria and Psv individually or in combination. Inoculations were performed in wounds previously made in three different sites of the main stem. Thirty replicate plants were used per strain. The plants were observed for symptom development and the number of bacteria on the inoculation sites was periodically evaluated, for up to 120 days after inoculation. To quantify the reduction of symptom expression, knots were excised from stems and their weights were compared between treatments. Inoculation with Psv resulted in the formation of knots with significantly higher weight values compared to plants inoculated simultaneously with Psv and antagonistic bacteria. Both tested bacterial also showed the capacity to reduce the amount of Psv in the inoculation sites, suggesting their effectiveness in controlling the multiplication of the pathogen. Data presented here demonstrate for the first time the potential of these bacteria for suppression of olive knot, and these two species should be considered in the future as potential biocontrol agents against Psv.This work is funded by FEDER funds through COMPETE (Programa Operacional Factores de Competitividade) and by national funds by FCT (Fundação para a Ciência e a Tecnologia) in the framework of the project EXCL/AGR-PRO/0591/2012. D. MINA thanks the Fundação para a Ciência e Tecnologia (FCT), Portugal for the Ph.D. grant SFRH/BD/105341/2014info:eu-repo/semantics/publishedVersio

    Endophytic fungal community succession in reproductive organs of two olive tree cultivars with contrasting anthracnose susceptibilities

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    The factors shaping endophytic fungal assemblages in reproductive organs have been less evaluated than in vegetative organs. Here, the temporal dynamics of fungal endophytes in inflorescences and fruits of olive tree cultivars with contrasting anthracnose susceptibilities was assessed, starting before flowers open until fruit ripening. Fungal diversity assessed by rRNA sequencing of cultivable isolates revealed a higher richness and abundance of endophytes in inflorescences than in fruits. Endophytes from Sordariomycetes were dominant in inflorescences, while in fruits they were from Dothideomycetes. The overall assemblages of inflorescences and fruits were shaped mainly by the plant organ, followed by the phenological stage and lastly, by the plant cultivar. The importance of cultivar as a shaping factor varied according to the plant organ, being only significant in inflorescence-associated endophytes. A set of fungal taxa were positively associated with a particular cultivar and phenological stage, likely contributing to the plant anthracnose resistance.This work is supported by FEDER funds through the COMPETE (Operational Programme for Competitiveness Factors) and by the Foundation for Science and Technology (FCT, Portugal) within the POCI-01-0145-FEDER-031133 (MicOlives) project and FCT/MCTES to CIMO (UIDB/00690/2020). F. Martins thanks the award of a PhD scholarship (ref. SFRH/BD/112234/2015) by FCT.info:eu-repo/semantics/publishedVersio

    Пов’язка для лікування гнійно-некротичних ран у хворих на цукровий діабет

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    Разработана и клинически апробирована повязка для лечения гнойно-некротических ран у больных сахарным диабетом. Её использование способствует значительному улучшению результатов лечения и эффективной реабилитации этой категории больных.Developed and clinically tested for the treatment of necrotic wounds in diabetic patients. Its use greatly improve the results of treatment and effective rehabilitation of these patients

    Presence and distribution of the African citrus psyllid in São Tomé island

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    The African citrus psyllid, Trioza erytreae (Hemiptera: Triozidae), is a natural vector of Candidatus Liberibacter spp., the causal agents of the citrus greening disease or Huanglongbing (HLB). Despite the global losses of the Citrus industry due to HLB, the vector is rapidly spread to new areas threatening citrus crops and raising con-cern for stakeholders. Until now, there was a single old register of T. er y treae from the São Tomé island (Bulletin of the British Museum of Natural History, Entomology, 49, 1–102). In this work, we provide up-to-date occurrence data on the presence of T. er y treae throughout the isle of São Tomé. The identity of the captured adults was assessed and confirmed through molecular identification by sequencing a portion of the mitochondrial COI. The psyllid was found in lemon, orange and tangerine or-chards. Further monitoring is advisable to manage potential outbreaksFundação para a Ciência e a Tecnologia, Grant/Award Number: LA/P/0007/2020 and UIDB/00690/2020; H2020 Environment, Grant/Award Number: H2020- SFS- 2018- 2 Topic SFS- 05- 2018-2019-2020; Foundation for Science and Technologyinfo:eu-repo/semantics/publishedVersio

    Особливості функціонування оцінних дієслівних лексем у публіцистичному дискурсі

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    Стаття присвячена дослідженню семантико-стилістичних особливостей оціночної дієслівної лексики в публіцистичному дискурсі, виділенню тематичних груп інгерентно та адгерентно оціночної дієслівної лексики, а також визначенню основних типів сенсибилізації оціночних дієслів-прагмем. Ключові слова: публіцистичний дискурс, дискурс, прагмема, іформема, дієслова інгерентної оцінки, адгерентно оціночні дієслова, дієслівна прагмема, сенсибілізація, лінгвістичні сенсибілізатори.Статья посвящена исследованию семантико-стилистических особенностей оценочной глагольной лексики в публицистическом дискурсе, выделению тематических групп ингерентно и адгерентно оценочной глагольной лексики, а также определению основных типов сенсибилизации оценочных глаголов-прагмем. Ключевые слова: публицистический дискурс, прагмема, информема, глаголы ингерентной оценки, адгерентно оценочные глаголы, глагольная прагмема, сенсибилизация, лингвистические сенсибилизаторы.The article is dedicated to study of the semantic-stylistic features of estimated verbal vocabulary in publicistic discourse, to allocation of thematic groups ingerentno and angerentno estimated verbal vocabulary, and also to definition of the basic types of a sensubulisation of estimated verbs-pragmem. Keywords: Publicistic discourse, pragmems, informem, the ingerentno estimated verbs, the angerentno estimated verbs, verbal pragmems, a sensubulisation, linguistic sensubulisator

    Evidence for a mixed mass composition at the `ankle' in the cosmic-ray spectrum

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    We report a first measurement for ultra-high energy cosmic rays of the correlation between the depth of shower maximum and the signal in the water Cherenkov stations of air-showers registered simultaneously by the fluorescence and the surface detectors of the Pierre Auger Observatory. Such a correlation measurement is a unique feature of a hybrid air-shower observatory with sensitivity to both the electromagnetic and muonic components. It allows an accurate determination of the spread of primary masses in the cosmic-ray flux. Up till now, constraints on the spread of primary masses have been dominated by systematic uncertainties. The present correlation measurement is not affected by systematics in the measurement of the depth of shower maximum or the signal in the water Cherenkov stations. The analysis relies on general characteristics of air showers and is thus robust also with respect to uncertainties in hadronic event generators. The observed correlation in the energy range around the `ankle' at lg(E/eV)=18.519.0\lg(E/{\rm eV})=18.5-19.0 differs significantly from expectations for pure primary cosmic-ray compositions. A light composition made up of proton and helium only is equally inconsistent with observations. The data are explained well by a mixed composition including nuclei with mass A>4A > 4. Scenarios such as the proton dip model, with almost pure compositions, are thus disfavoured as the sole explanation of the ultrahigh-energy cosmic-ray flux at Earth.Comment: Published version. Added journal reference and DOI. Added Report Numbe

    Prevalence of potential drug-drug interactions in the intensive care unit of a Brazilian teaching hospital

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    Abstract Patients in intensive care unit are prescribed large numbers of drugs, highlighting the need to study potential Drug-Drug Interactions in this environment. The aim of this study was to delineate the prevalence and risk of potential drug-drug interactions between medications administered to patients in an ICU. This cross-sectional observational study was conducted during 12 months, in an adult ICU of a teaching hospital. Inclusion criteria were: prescriptions with 2 or more drugs of patients admitted to the ICU for > 24 hours and age of ≥18 years. Potential Drug-Drug Interactions were quantified and classified through MicromedexTM database. The 369 prescriptions included in this study had 205 different drugs, with an average of 13.04 ± 4.26 (mean ± standard deviation) drugs per prescription. Potential Drug-Drug Interactions were identified in 89% of these, with an average of 5.00 ± 5.06 interactions per prescription. Of the 405 different pairs of potentially interacting drugs identified, moderate and major interactions were present in 74% and 67% of prescriptions, respectively. The most prevalent interaction was between dipyrone and enoxaparin (35.8%), though its clinical occurrence was not observed in this study. The number of potential Drug-Drug Interactions showed significant positive correlations with the length of stay in the intensive care unit, and with the number of prescribed drugs. Acknowledging the high potential for Drug-Drug Interactions in the ICU represents an important step toward improving patient safety and best therapy results
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