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1.
Phytopathology ; 114(5): 910-916, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38330057

RESUMO

The landscape of scientific publishing is experiencing a transformative shift toward open access, a paradigm that mandates the availability of research outputs such as data, code, materials, and publications. Open access provides increased reproducibility and allows for reuse of these resources. This article provides guidance for best publishing practices of scientific research, data, and associated resources, including code, in The American Phytopathological Society journals. Key areas such as diagnostic assays, experimental design, data sharing, and code deposition are explored in detail. This guidance aligns with that observed by other leading journals. We hope the information assembled in this paper will raise awareness of best practices and enable greater appraisal of the true effects of biological phenomena in plant pathology.


Assuntos
Patologia Vegetal , Reprodutibilidade dos Testes , Editoração/normas , Guias como Assunto , Acesso à Informação , Disseminação de Informação
2.
Plant Dis ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771322

RESUMO

Meta-analysis (MA) is increasingly adopted in agricultural and ecological sciences, fields at the interface with plant pathology. Our review on the use of MA in the field, since 1999, identified 79 original research papers. Fifty percent of these works were published in two APS journals, emphasizing their central role in disseminating MA research. Analysis of the number of authors per study and the authorship network revealed a tightly knit field. The network shows a few "hub" authors or groups that significantly influence research directions, with a clear geographical clustering in North and South America. Most of the MA papers focused on the effects of disease control, where fungicide was the main product. The MA investigations often focus on response variables like yield and disease severity for which the analyzed effect sizes differ, but the log of the ratio of means and untransformed means are predominant. The study selection to be included in the MA often follows systematic review standards or when clear quantitative criteria are used for study inclusion. Yet, the inclusion of data from reports, newsletters, and research trial data adds breadth. Frequentist rather than Bayesian inference is most common and SAS and R are the preferred software. Our review underscores the escalating importance of MA in plant pathology, especially for determining the mean and variability of the effects of different control methods on disease and yield. Efforts should continue to improve the detailed reporting of MA methods used, data sharing and reporting of measures of heterogeneity among studies.

3.
Phytopathology ; 113(2): 225-238, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35994731

RESUMO

Fusarium head blight (FHB), caused by the fungus Fusarium graminearum, is associated with grain contamination with mycotoxins such as deoxynivalenol (DON) and zearalenone (ZEA). Unlike DON, less is known about factors affecting ZEA production during FHB epidemics. The objective of this study was to quantify ZEA contamination of wheat grain as influenced by temperature, relative humidity, FHB index (IND), grain maturation, simulated late-season rainfall, and harvest timing. Mean ZEA concentrations were low (<1.1 ppm) during the early stages of grain development (25 to 31 days after anthesis [DAA]) but rapidly increased 35 to 51 DAA in field experiments, particularly under rainy conditions. Five or ten consecutive days with simulated rainfall shortly before harvest greatly increased ZEA contamination. Similarly, extremely high levels of ZEA (51.8 to 468.6 ppm) were observed in grain from spikes exposed to 100% relative humidity (RH) at all tested temperatures and mean IND levels under controlled conditions. Interestingly, at RH ≤ 90%, ZEA concentrations were very low (0.1 to 3.6 ppm) at all tested temperatures, even at IND above 90%. At 100% RH, mean ZEA contamination was significantly higher at 20 and 25°C (235.1 and 278.2 ppm) than at 30°C (104.7 ppm). Grain harvested early and not exposed to rainfall had lower mean ZEA than grain harvested late and/or subjected to preharvest rainfall. This study was the first to associate ZEA contamination of grain from FHB-affected wheat spikes with temperature and moisture and show through designed experiments that early harvest could be a useful strategy for reducing ZEA contamination.


Assuntos
Fusarium , Micotoxinas , Tricotecenos , Zearalenona , Zearalenona/farmacologia , Triticum/microbiologia , Doenças das Plantas/microbiologia , Grão Comestível/microbiologia
4.
Phytopathology ; 113(8): 1483-1493, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36880796

RESUMO

Constructing models that accurately predict Fusarium head blight (FHB) epidemics and are also amenable to large-scale deployment is a challenging task. In the United States, the emphasis has been on simple logistic regression (LR) models, which are easy to implement but may suffer from lower accuracies when compared with more complicated, harder-to-deploy (over large geographies) model frameworks such as functional or boosted regressions. This article examined the plausibility of random forests (RFs) for the binary prediction of FHB epidemics as a possible mediation between model simplicity and complexity without sacrificing accuracy. A minimalist set of predictors was also desirable rather than having the RF model use all 90 candidate variables as predictors. The input predictor set was filtered with the aid of three RF variable selection algorithms (Boruta, varSelRF, and VSURF), using resampling techniques to quantify the variability and stability of selected variable sets. Post-selection filtering produced 58 competitive RF models with no more than 14 predictors each. One variable representing temperature stability in the 20 days before anthesis was the most frequently selected predictor. This was a departure from the prominence of relative humidity-based variables previously reported in LR models for FHB. The RF models had overall superior predictive performance over the LR models and may be suitable candidates for use by the Fusarium Head Blight Prediction Center.

5.
Phytopathology ; 113(2): 206-224, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36131392

RESUMO

Fusarium head blight (FHB) of wheat, caused by the fungus Fusarium graminearum, is associated with grain contamination with mycotoxins such as deoxynivalenol (DON). Although FHB is often positively correlated with DON, this relationship can break down under certain conditions. One possible explanation for this could be the conversion of DON to DON-3-glucoside (D3G), which is typically missed by common DON testing methods. The objective of this study was to quantify the effects of temperature, relative humidity (RH), and preharvest rainfall on DON, D3G, and the D3D/DON relationship. D3G levels were higher in grain from spikes exposed to 100% RH than to 70, 80, or 90% RH at 20 and 25°C across all tested levels of mean FHB index (percentage of diseased spikelets per spike). Mean D3G contamination was higher at 20°C than at 25 or 30°C. There were significantly positive linear relationships between DON and D3G. Rainfall treatments resulted in significantly higher mean D3G than the rain-free check and induced preharvest sprouting, as indicated by low falling numbers (FNs). There were significant positive relationships between the rate of increase in D3G per unit increase in DON (a measure of conversion) and sprouting. As FN decreased, the rate of D3G conversion increased, and this rate of conversion per unit decrease in FN was greater at relatively low than at high mean DON levels. These results provide strong evidence that moisture after FHB visual symptom development was associated with DON-to-D3G conversion and constitute valuable new information for understanding this complex disease-mycotoxin system.


Assuntos
Fusarium , Micotoxinas , Triticum/microbiologia , Doenças das Plantas/microbiologia , Grão Comestível
6.
PLoS Comput Biol ; 17(3): e1008831, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33720929

RESUMO

Ensembling combines the predictions made by individual component base models with the goal of achieving a predictive accuracy that is better than that of any one of the constituent member models. Diversity among the base models in terms of predictions is a crucial criterion in ensembling. However, there are practical instances when the available base models produce highly correlated predictions, because they may have been developed within the same research group or may have been built from the same underlying algorithm. We investigated, via a case study on Fusarium head blight (FHB) on wheat in the U.S., whether ensembles of simple yet highly correlated models for predicting the risk of FHB epidemics, all generated from logistic regression, provided any benefit to predictive performance, despite relatively low levels of base model diversity. Three ensembling methods were explored: soft voting, weighted averaging of smaller subsets of the base models, and penalized regression as a stacking algorithm. Soft voting and weighted model averages were generally better at classification than the base models, though not universally so. The performances of stacked regressions were superior to those of the other two ensembling methods we analyzed in this study. Ensembling simple yet correlated models is computationally feasible and is therefore worth pursuing for models of epidemic risk.


Assuntos
Biologia Computacional/métodos , Epidemias/estatística & dados numéricos , Modelos Estatísticos , Algoritmos , Fusarium , Doenças das Plantas/estatística & dados numéricos , Triticum/microbiologia
7.
Phytopathology ; 112(2): 315-334, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34058859

RESUMO

Because Fusarium head blight (FHB) intensity is usually highly variable within a plot, the number of spikes rated for FHB index (IND) quantification must be considered when designing experiments. In addition, quantification of sources of IND heterogeneity is crucial for defining sampling protocols. Field experiments were conducted to quantify the variability of IND ("field severity") at different spatial scales and to investigate the effects of sample size on estimated plot-level mean IND and its accuracy. A total of 216 7-row × 6-m-long plots of a moderately resistant and a susceptible cultivar were spray-inoculated with different Fusarium graminearum spore concentrations at anthesis to generate a range of IND levels. A one-stage cluster sampling approach was used to estimate IND, with an average of 32 spikes rated at each of 10 equally spaced points per plot. Plot-level mean IND ranged from 0.9 to 37.9%. Heterogeneity of IND, quantified by fitting unconditional hierarchical linear models, was higher among spikes within clusters than among clusters within plots or among plots. The projected relative error of mean IND increased as mean IND decreased, and as sample size decreased to <100 spikes per plot. Simple random samples were drawn with replacement 50,000 times from the original dataset for each plot and used to estimate the effects of sample sizes on mean IND. Samples of 100 or more spikes resulted in more precise estimates of mean IND than smaller samples. Poor sampling may result in inaccurate estimates of IND and poor interpretation of results.


Assuntos
Fusarium , Tricotecenos , Doenças das Plantas , Tamanho da Amostra , Triticum
8.
Plant Dis ; 106(12): 3061-3075, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35536201

RESUMO

The impact of Gibberella ear rot (GER; caused by Fusarium graminearum) on deoxynivalenol (DON) contamination of grain and yield components in maize were investigated using data from 30 environments in Ohio (3 years by 10 locations). Fifteen hybrids, later classified as susceptible (SU), moderately susceptible (MS), or moderately resistant (MR), based on the magnitude of differences in mean arcsine square-root-transformed GER severity (arcSEV) and log-transformed DON (logDON) relative to a reference SU check, were planted in each environment, and 10 ears per hybrid were inoculated with a spore suspension of F. graminearum. Relationships between GER severity and DON were well described by a Kono-Sugino-type nonlinear equation. Estimated parameters representing height (A) and steepness (ß) of the curves were significantly higher for SU than MS and MR hybrids but A was not significantly different between MS and MR. Results from a surrogacy analysis showed that GER was a moderate trial- and individual-level surrogate for DON. Both grain weight per ear and ear diameter decreased with increasing arcSEV but the regression slopes varied among resistance classes. The rates of reduction in both yield components per unit increase in arcSEV were significantly greater for SU than for MS and MR. An estimated 50% reduction in grain weight occurred at 62% GER severity for SU, compared with 77% severity for MS and 83% for MR. These results show that GER severity can be used as a surrogate for early estimation of DON contamination and yield loss to help guide grain handling and marketing decisions.


Assuntos
Gibberella , Gibberella/genética , Zea mays , Doenças das Plantas , Grão Comestível , Sementes
9.
Plant Dis ; 106(11): 2839-2855, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35471074

RESUMO

Field experiments were conducted to investigate the efficacy of fungicide treatments in combination with genetic resistance against Fusarium head blight (FHB) and its associated mycotoxins under persistently wet pre- and postanthesis conditions in plots inoculated with Fusarium graminearum-colonized corn spawn. Treatments consisted of a single application of prothioconazole + tebuconazole at early anthesis (PA), or at 3 (P3), 6 (P6), or 9 (P9) days after early anthesis, or PA followed by a single application of metconazole at 3 (PA+C3), 6 (PA+C6), or 9 (PA+C9) days after early anthesis. PA and P3 were the most efficacious of the single-application treatments in terms of mean percentage control of FHB index (IND), deoxynivalenol (DON), zearalenone (ZEA), and mean increase in grain yield and test weight (TW) relative to the nontreated susceptible check (S_CK). The double-application treatments (PA+C3, PA+C6, and PA+C9) were the most effective of all tested fungicide programs. However, relative to S_CK, the highest overall mean percentage reduction in IND, DON, and ZEA and increase in grain yield and TW were observed when the double-application fungicide programs were integrated with genetic resistance. The estimated net cash income (NCI) of the integrated management (IM) programs was consistently higher than the NCI of other tested programs across different grain prices and fungicide application costs. Thus, the benefits of the two-treatment IM programs under highly favorable conditions for FHB development were enough to offset the cost of two applications, making these programs profitable.


Assuntos
Fungicidas Industriais , Fusarium , Micotoxinas , Zearalenona , Triticum/genética , Fungicidas Industriais/farmacologia , Micotoxinas/farmacologia , Doenças das Plantas/prevenção & controle , Grão Comestível
10.
Phytopathology ; 111(11): 1983-1993, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33769833

RESUMO

The binary power law (BPL) is often used to characterize spatial heterogeneity of disease incidence. A hierarchical mixed model, coupled with multiple imputation to randomly generate any missing standard errors, was used to conduct a meta-analysis of >200 published values of the estimated aggregation (b) parameter of the BPL. Approximately 50% of estimated b values ranged from 1.1 to 1.3. Moderator variable analysis showed that the number of individuals per sampling unit (n) had a strong positive effect on b, with a linear relation between estimated b and ln(n). Estimated expected value of b for the population of published regressions at a reference n of 15 was 1.22. The increase in the variance due to the imputations was only 0.03, and the efficiency exceeded 0.98. Results were confirmed with an alternative mixed model that considered a range of possible within-trial correlations of the estimated b values and with a random-coefficient mixed model fitted to the subset of the data. Cropping system, dispersal mode, and pathogen type all had significant effects on b, with annuals having larger expected value than woody perennials, soilborne and rain-splashed dispersed pathogens having the largest expected values for dispersal mode, and bacteria and oomycetes having the largest expected values for pathogen type. However, there was considerable variation within each of the levels of the moderators, and the differences of expected values from smallest to largest were small, ≤0.16. Results are discussed in relation to previously published findings from stochastic simulations.


Assuntos
Doenças das Plantas , Plantas , Incidência , Chuva
11.
Phytopathology ; 111(12): 2250-2267, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34009008

RESUMO

Models were developed to quantify the risk of deoxynivalenol (DON) contamination of maize grain based on weather, cultural practices, hybrid resistance, and Gibberella ear rot (GER) intensity. Data on natural DON contamination of 15 to 16 hybrids and weather were collected from 10 Ohio locations over 4 years. Logistic regression with 10-fold cross-validation was used to develop models to predict the risk of DON ≥1 ppm. The presence and severity of GER predicted DON risk with an accuracy of 0.81 and 0.87, respectively. Temperature, relative humidity, surface wetness, and rainfall were used to generate 37 weather-based predictor variables summarized over each of six 15-day windows relative to maize silking (R1). With these variables, least absolute shrinkage and selection operator (LASSO) followed by all-subsets variable selection and logistic regression with 10-fold cross-validation were used to build single-window weather-based models, from which 11 with one or two predictors were selected based on performance metrics and simplicity. LASSO logistic regression was also used to build more complex multiwindow models with up to 22 predictors. The performance of the best single-window models was comparable to that of the best multiwindow models, with accuracy ranging from 0.81 to 0.83 for the former and 0.83 to 0.87 for the latter group of models. These results indicated that the risk of DON ≥1 ppm can be accurately predicted with simple models built using temperature- and moisture-based predictors from a single window. These models will be the foundation for developing tools to predict the risk of DON contamination of maize grain.


Assuntos
Fusarium , Tricotecenos , Contaminação de Alimentos , Modelos Logísticos , Doenças das Plantas , Zea mays
12.
Plant Dis ; 105(1): 96-107, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33197378

RESUMO

Epidemics of wheat blast, caused the Triticum pathotype of Magnaporthe oryzae, were studied in the Santa Cruz del la Sierra region of Bolivia to quantify and compare the temporal dynamics of the disease under different growing conditions. Six plots of a susceptible wheat cultivar were planted at Cuatro Cañadas (CC), Okinawa 1 (OK1), and Okinawa 2 (OK2) in 2015. Spike blast incidence (INC) and severity (SEV) and leaf blast severity (LEAF) were quantified in each plot at regular intervals on a 10 × 10 grid (n = 100 clusters of spikes), beginning at head emergence (Feekes growth stage 10.5), for a total of nine assessments at CC, six at OK1, and six at OK2. Spike blast increased over time for 20 to 30 days before approaching a mean INC of 100% and a mean SEV of 60 to 75%. The logistic model was the most appropriate for describing the temporal dynamics of spike blast. The highest absolute rates of disease increase occurred earliest at OK1 and latest at OK2, and in all cases it coincided with major rain events. Estimated y0 values (initial blast intensity) were significantly (P < 0.05) higher at OK1 than at CC or OK2, whereas rL values (the logistic rate parameter) were significantly higher at OK2 than at CC or OK1. It took about 10 fewer days for SEV to reach 10, 15, or 20% at OK1 compared with OK2 and CC. Based on survival analyses, the survivor functions for time to 10, 15 and 20% SEV (ts) were significantly different between OK1 and the other locations, with the probabilities of SEV reaching the thresholds being highest at OK1. LEAF at 21 days after Feekes 10.5 had a significant effect on ts at OK1. For every 5% increase in LEAF, the chance of SEV reaching the thresholds by day 21 increased by 30 to 55%.


Assuntos
Epidemias , Magnaporthe , Ascomicetos , Bolívia , Doenças das Plantas , Triticum
13.
Phytopathology ; 110(10): 1632-1646, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32370661

RESUMO

Sometimes plant pathologists assess disease intensity when they are primarily interested in other response variables, such as yield loss or toxin concentration in harvested products. In these situations, disease intensity potentially could be considered a surrogate of yield or toxin. A surrogate is a variable which can be used instead of the variable of interest in the evaluation of experimental treatments or in making predictions. Surrogates can be measured earlier, more conveniently, or more cheaply than the variable of primary interest, but the reliability or validity of the surrogate must be shown. We demonstrate ways of quantifying two facets of surrogacy by using a protocol originally developed by Buyse and colleagues for medical research. Coefficient-of-determination type statistics can be used to conveniently assess the strength of surrogacy on a unitless scale. As a case study, we evaluated whether field severity of Fusarium head blight (i.e., FHB index) can be used as a surrogate for yield loss and deoxynivalenol (DON) toxin concentration in harvested wheat grain. Bivariate mixed models and corresponding approximations were fitted to data from 82 uniform fungicide trials conducted from 2008 to 2013. Individual-level surrogacy-for predicting the variable of interest (yield or DON) from the surrogate (index) in plots with the same treatment-was very low. Trial-level surrogacy-for predicting the effect of treatment (e.g., mean difference) for the variable of interest based on the effect of the treatment on the surrogate (index)-was moderate for yield, and only low for DON. Challenges in using disease severity as a surrogate for yield and toxin are discussed.


Assuntos
Fusarium , Tricotecenos , Doenças das Plantas , Reprodutibilidade dos Testes , Triazóis , Triticum
14.
Plant Dis ; 104(10): 2622-2633, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32804014

RESUMO

The Triticum pathotype of Magnaporthe oryzae (MoT) that causes wheat blast has not yet been reported in the U.S., but the closely related M. oryzae Lolium pathotype (MoL), also capable of inciting blast, is found in several wheat growing regions. Since the epidemiology of MoL-incited wheat blast is unknown, it is difficult to project where and under what conditions this pathogen may be of importance. To quantify conditions favorable for MoL infection and temporal development of wheat blast, separate cohorts of wheat spikes were spray or point inoculated at anthesis and immediately subjected to different combinations of temperature (TEMP; 20, 25, and 30°C) and 100% relative humidity (RH) duration (0, 3, 6, 12, 24, and 48 h). Blast developed under all tested conditions, with both incidence (INC) and severity (SEV) increasing over time. The effects of TEMP on angular-transformed INC and SEV (arcINC and arcSEV) were significant (P < 0.05) in most cases, with the magnitude of the TEMP effect influenced by RH duration when spikes were spray-inoculated. Between 12 and 21 days after inoculation (DAI), there were significant, positive linear relationships between hours of high RH and arcINC and arcSEV at 25 and 30°C, but not at 20°C. The estimated rates of increase in transformed INC or SEV per hour increase in high RH duration were significantly higher at 30°C than at 25°C at 12 to 14 DAI, but not at 19 to 21 DAI. The highest estimated temporal rates of increase in INC and SEV and the shortest estimated incubation periods (5 to 8 days) occurred at 25 and 30°C, with 24 and 48 h of high RH immediately after inoculation. These results will contribute to ongoing efforts to better understand the epidemiology of wheat blast incited by MoL as well as MoT.


Assuntos
Lolium , Magnaporthe , Umidade , Doenças das Plantas , Temperatura , Triticum
15.
Eur J Clin Microbiol Infect Dis ; 38(3): 505-514, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30707378

RESUMO

Respiratory tract infections (RTI) are more commonly caused by viral pathogens in children than in adults. Surprisingly, little is known about antibiotic use in children as compared to adults with RTI. This prospective study aimed to determine antibiotic misuse in children and adults with RTI, using an expert panel reference standard, in order to prioritise the target age population for antibiotic stewardship interventions. We recruited children and adults who presented at the emergency department or were hospitalised with clinical presentation of RTI in The Netherlands and Israel. A panel of three experienced physicians adjudicated a reference standard diagnosis (i.e. bacterial or viral infection) for all the patients using all available clinical and laboratory information, including a 28-day follow-up assessment. The cohort included 284 children and 232 adults with RTI (median age, 1.3 years and 64.5 years, respectively). The proportion of viral infections was larger in children than in adults (209(74%) versus 89(38%), p < 0.001). In case of viral RTI, antibiotics were prescribed (i.e. overuse) less frequently in children than in adults (77/209 (37%) versus 74/89 (83%), p < 0.001). One (1%) child and three (2%) adults with bacterial infection were not treated with antibiotics (i.e. underuse); all were mild cases. This international, prospective study confirms major antibiotic overuse in patients with RTI. Viral infection is more common in children, but antibiotic overuse is more frequent in adults with viral RTI. Together, these findings support the need for effective interventions to decrease antibiotic overuse in RTI patients of all ages.


Assuntos
Antibacterianos/uso terapêutico , Gestão de Antimicrobianos/normas , Prescrição Inadequada/estatística & dados numéricos , Infecções Respiratórias/tratamento farmacológico , Idoso , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/epidemiologia , Pré-Escolar , Feminino , Humanos , Lactente , Israel/epidemiologia , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Estudos Prospectivos , Padrões de Referência , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/epidemiologia , Viroses/diagnóstico , Viroses/tratamento farmacológico , Viroses/epidemiologia
16.
Plant Dis ; 102(12): 2500-2510, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30358506

RESUMO

Anthesis is generally recommended as the optimum growth stage for applying a foliar fungicide to manage Fusarium head blight (FHB) and the Fusarium-associated toxin deoxynivalenol (DON) in wheat. However, because it is not always possible to treat fields at anthesis, studies were conducted to evaluate pre- and postanthesis treatment options for managing FHB and DON in spring and winter wheat. Network meta-analytical models were fitted to data from 19 years of fungicide trials, and log response ratio ([Formula: see text]) and approximate percent control ([Formula: see text]) relative to a nontreated check were estimated as measures of the effects of six treatments on FHB index (IND: mean percentage of diseased spikelets per spike) and DON. The evaluated treatments consisted of either Caramba (metconazole) applied early (at heading [CE]), at anthesis (CA), or late (5 to 7 days after anthesis; CL), or Prosaro (prothioconazole + tebuconazole) applied at the same three times and referred to as PE, PA, and PL, respectively. All treatments reduced mean IND and DON relative to the nontreated check, but the magnitude of the effect varied with timing and wheat type. CA and PA resulted in the highest [Formula: see text] values for IND, 52.2 and 51.5%, respectively, compared with 45.9% for CL, 41.3% for PL, and less than 33% for CE and PE. Anthesis and postanthesis treatments reduced mean IND by 14.9 to 29.7% relative to preanthesis treatments. The estimated effect size was also statistically significant for comparisons between CA and CL and PA and PL; CA reduced IND by 11.7% relative to CL, whereas PA reduced the disease by 17.4% relative to PL. Differences in efficacy against IND between pairs of prothioconazole + tebuconazole and metconazole treatments applied at the same timing (CE versus PE, CA versus PA, and CL versus PL) were not statistically significant. However, CA and CL outperformed PA and PL by 7 and 12.8%, respectively, in terms of efficacy against DON. All application programs had comparable efficacy against IND between spring and winter wheat types, but efficacy against DON was 10 to 16% greater for spring than winter wheat for applications made at or after anthesis. All programs led to an increase in mean grain yield and test weight relative to the nontreated check.


Assuntos
Fungicidas Industriais/farmacologia , Fusarium/efeitos dos fármacos , Doenças das Plantas/prevenção & controle , Tricotecenos/farmacologia , Triticum/microbiologia , Desmetilação , Doenças das Plantas/microbiologia , Triazóis/farmacologia
17.
Pharm Stat ; 17(3): 264-277, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29676023

RESUMO

Network meta-analysis can be implemented by using arm-based or contrast-based models. Here we focus on arm-based models and fit them using generalized linear mixed model procedures. Full maximum likelihood (ML) estimation leads to biased trial-by-treatment interaction variance estimates for heterogeneity. Thus, our objective is to investigate alternative approaches to variance estimation that reduce bias compared with full ML. Specifically, we use penalized quasi-likelihood/pseudo-likelihood and hierarchical (h) likelihood approaches. In addition, we consider a novel model modification that yields estimators akin to the residual maximum likelihood estimator for linear mixed models. The proposed methods are compared by simulation, and 2 real datasets are used for illustration. Simulations show that penalized quasi-likelihood/pseudo-likelihood and h-likelihood reduce bias and yield satisfactory coverage rates. Sum-to-zero restriction and baseline contrasts for random trial-by-treatment interaction effects, as well as a residual ML-like adjustment, also reduce bias compared with an unconstrained model when ML is used, but coverage rates are not quite as good. Penalized quasi-likelihood/pseudo-likelihood and h-likelihood are therefore recommended.


Assuntos
Bases de Dados Factuais/estatística & dados numéricos , Modelos Lineares , Metanálise em Rede , Bases de Dados Factuais/normas , Humanos
18.
Plant Dis ; 101(11): 1910-1917, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30677315

RESUMO

Strawberry production in Florida and South Carolina is affected by two major diseases, anthracnose fruit rot (AFR) and Botrytis fruit rot (BFR), caused by Colletotrichum acutatum and Botrytis cinerea, respectively. The effective management of both diseases traditionally relied on weekly fungicide applications. However, to improve timing and reduce the number of fungicide sprays, many growers follow the Strawberry Advisory System (StAS), a decision support system for forecasting fungicide applications based on environmental conditions and previously developed models. The objective of this study was to perform a meta-analysis to determine the effectiveness of the StAS for AFR and BFR management compared with a calendar-based spray program. Thirty-nine trials were conducted from 2009 to 2014 in Florida and South Carolina commercial strawberry fields. Meta-analysis was conducted to quantify the treatment effects on four effect sizes, all based on the difference in response variables for StAS and the calendar-based treatments in each trial. The mean difference in BFR incidence, AFR incidence, yield, and number of marketable fruit between the two treatments was not significantly different from 0 (P < 0.05). However, the number of fungicide applications per season was reduced by a median of seven when using the StAS, a 50% reduction in sprays compared with the calendar-based approach. Effect sizes were not influenced by location or the favorability of the environment for disease development. These findings indicate that use of StAS in commercial fields is effective in controlling fruit rot diseases with no reduction in yield while substantially reducing fungicide applications.


Assuntos
Botrytis , Colletotrichum , Fragaria , Internet , Doenças das Plantas/prevenção & controle , Botrytis/fisiologia , Colletotrichum/fisiologia , Previsões , Fragaria/microbiologia , Frutas/microbiologia , Internet/tendências , Doenças das Plantas/microbiologia , Sudeste dos Estados Unidos
19.
J Proteome Res ; 15(3): 826-39, 2016 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-26813582

RESUMO

There are over 500 candidate secreted effector proteins (CSEPs) or Blumeria effector candidates (BECs) specific to the barley powdery mildew pathogen Blumeria graminis f.sp. hordei. The CSEP/BEC proteins are expressed and predicted to be secreted by biotrophic feeding structures called haustoria. Eight BECs are required for the formation of functional haustoria. These include the RNase-like effector BEC1054 (synonym CSEP0064). In order to identify host proteins targeted by BEC1054, recombinant BEC1054 was expressed in E. coli, solubilized, and used in pull-down assays from barley protein extracts. Many putative interactors were identified by LC-MS/MS after subtraction of unspecific binders in negative controls. Therefore, a directed yeast-2-hybrid assay, developed to measure the effectiveness of the interactions in yeast, was used to validate putative interactors. We conclude that BEC1054 may target several host proteins, including a glutathione-S-transferase, a malate dehydrogenase, and a pathogen-related-5 protein isoform, indicating a possible role for BEC1054 in compromising well-known key players of defense and response to pathogens. In addition, BEC1054 interacts with an elongation factor 1 gamma. This study already suggests that BEC1054 plays a central role in barley powdery mildew virulence by acting at several levels.


Assuntos
Hordeum/química , Interações Hospedeiro-Patógeno , Proteínas de Plantas/imunologia , Mapeamento de Interação de Proteínas/métodos , Ascomicetos/patogenicidade , Proteínas Fúngicas/toxicidade , Proteínas de Plantas/análise , Ligação Proteica , Espectrometria de Massas em Tandem , Virulência , Leveduras/patogenicidade
20.
Eur J Cancer Care (Engl) ; 25(3): 419-27, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26239724

RESUMO

Over 14 000 patients aged 15-24 are estimated to be diagnosed with cancer in the European Union (EU) each year. Teenagers and young adults (TYA) often fall down gaps between children's and adults cancer services. The specific challenges of providing optimal care to them are described, but we present a summary of recent progress. Progress to overcome these challenges is happening at different rates across Europe. We summarise the European national projects in this field but more recently we have seen the beginnings of European coordination. Within the EU 7th Funding Programme (FP7) European Network for Cancer Research in Children and Adolescents programme (ENCCA), a specific European Network for Teenagers and Young Adults with Cancer has held a series of scientific meetings, including professionals, patients and caregivers. This group has proposed unanswered research questions and agreed key features of a high-quality service that can improve outcomes for TYA with cancer, including the primacy of collaboration between adult and paediatric services to eliminate the gap in the management of TYA with cancer.


Assuntos
Neoplasias/epidemiologia , Adolescente , Pesquisa Biomédica/organização & administração , Atenção à Saúde/organização & administração , Europa (Continente)/epidemiologia , União Europeia , Humanos , Cooperação Internacional , Oncologia/organização & administração , Neoplasias/psicologia , Neoplasias/terapia , Adulto Jovem
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