Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 37
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Plant Dis ; 108(9): 2838-2844, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38736151

RESUMEN

Grapevine anthracnose, caused by Elsinoë ampelina, is one of the most devastating diseases for wine and table grapes, particularly in hot, humid regions. This study explores how temperature and leaf age affect incubation and how temperature affects lesion development and sporulation. The influence of temperature and leaf age on incubation period (days) was tested under controlled conditions. Leaves from 1 to 8 days old were inoculated and maintained at temperatures of 5, 10, 15, 20, 25, and 30°C. The time elapsed between inoculation and the emergence of initial lesions was recorded. The effect of temperature on lesion development and sporulation was investigated under vineyard conditions. This was achieved through artificial inoculations, with 17, 11, and 11 inoculations conducted in 2016, 2017, and 2018, respectively. The average incubation period, considering all leaf ages, was 27.50 days at 5°C, 15.10 days at 10°C, 9.70 days at 15°C, 5.90 days at 20°C, 3.70 days at 25°C, and 2.26 days at 30°C. Regardless of temperature, the average incubation period was 3.6, 5.9, 8.3, 9.8, 11.9, 13.4, 15.6, and 17.1 days for leaves 1, 2, 3, 4, 5, 6, 7, and 8 days old, respectively. The exponential decay model accurately describes the incubation period as a function of both temperature and leaf age. On average, the relative lesion development (RLD) was 0.00, 0.00, 0.23, 0.47, 0.72, 0.93, 0.92, 0.90, 0.94, and 1.0 at 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 days after inoculation, respectively. The average relative sporulation (RSPO) was 0.03, 0.36, 0.82, 0.96, and 1.0 at 5, 10, 15, 20, and 25 days after inoculation, respectively. Both RLD and RSPO as a function of degree-days (Tbase = 0°C) since inoculation were well described by the logistic function. The rates of change in RLD and RSPO were 0.055 and 0.032, respectively. The results of this study provide new quantitative insights into three important stages (monocyclic processes) in the development of grapevine anthracnose caused by E. ampelina.


Asunto(s)
Enfermedades de las Plantas , Hojas de la Planta , Temperatura , Vitis , Vitis/microbiología , Enfermedades de las Plantas/microbiología , Hojas de la Planta/microbiología , Ascomicetos/fisiología , Esporas Fúngicas/fisiología
2.
Plant Dis ; 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38907522

RESUMEN

Grapevine enamovirus 1 (GEV1) belongs to the genus Enamovirus, in the family Solemoviridae. It has been reported from several countries infecting grapevines including Brazil (Silva et al. 2017), China (Ren et al. 2021) and France (Hily et al. 2022). To assess the prevalence and diversity of economically important grapevine viruses in nine Canadian vineyards, total RNA and double-stranded RNA (dsRNA) (Fall et al. 2020) were extracted from 30 and 100 composite samples respectively, with each consisting of five vines of the same cultivars. The cultivars included in this study are Frontenac noir (n=34), Vidal (n=32), Marquette (n=33), Riesling (n=31), and Pinot noir (n=31). The total RNA and dsRNA samples were subsequently multiplexed and diagnosed by high-throughput sequencing (HTS) on NovaSeq (600 S4 PE100) and MiSeq (2 × 250 cycle PE) respectively. From NovaSeq and MiSeq sequencing, an average of 410,000 to 1.3 million reads/sample were obtained, respectively, with mapped viral reads representing 10.92% to 12.48% of the total reads. After sequence quality was verified using Trimmomatic v.0.40 (Bolger et al. 2014), the clean sequences were screened against all possible viruses in the databases using the Virtool (Rott et al. 2017) and VirFind virus detection pipelines (Ho and Tzanetakis 2014). GEV1 was detected in clean sequences from two, three, and two leaf samples of cultivars 'Marquette' 'Riesling' and 'Frontenac noir' respectively. Six of the seven HTS-assembled GEV1 genomes were partial, ranging from 4,523 to 6,000 nucleotide (nt) with genome coverage varying from 71% to 89%. Only one 6,314 nt long assembled contig (Accession No. OR021829), represented a nearly complete genome, being only 53 and 3 nt shorter than Sd-CG (MT536978) at 5' and 3' untranslated regions (UTR), respectively. Isolate 3- Riesling-CAN (OR021829) shares 90.56 to 94.19% nt identities with several GEV1isolates at 96-99% of query coverage. Phylogenetically, OR021829 is closer to GEV1 isolates from France and China (Figure S1). To validate the HTS results, the developed primer pair SetF and Set1R (Silva et al., 2017) was used for RT-PCR detection. The amplicons from all seven HTS-positive samples were sequenced using Sanger sequencing, confirming the presence of GEV-1 in three studied grape cultivars in Canadian vineyards. Symptoms associated with the specific GEV1-infected vines could not be explained as composite samples were used. Each of the combined samples HTS library also tested positive for at least one of the known grape virus/viroids, namely grapevine leafroll associated-virus -3, grapevine pinot gris virus, grapevine rupestris stem pitting-associated virus, Marafivirus syrahense grapevine Syrah virus-1 and hop stunt viroid. To our knowledge, this is the first report of GEV1 being detected in grapevines in Canada, or in any North American vineyard. GEV1 is a relatively new virus, and its biology remains largely unknown. Based on this sequence new GEV1 primers can be developed to know the genetic variability among GEV-1 and improve the detection of this virus in vineyards.

3.
Plant Dis ; 107(11): 3389-3393, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37227441

RESUMEN

Climate change is impacting agriculture in many ways, and a contribution from all is required to reduce the imminent losses related to it. Recently, it has been shown that citizen science could be a way to trace the impact of climate change. However, how can citizen science be applied in plant pathology? Here, using as an example a decade of phytoplasma-related diseases reported by growers, agronomists, and citizens in general, and confirmed by a government laboratory, we explored how to better value plant pathogen monitoring data. Through this collaboration, we found that in the last decade, 34 hosts have been affected by phytoplasmas; 9, 13, and 5 of these plants were, for the first time, reported phytoplasma hosts in eastern Canada, all of Canada, and worldwide, respectively. Another finding of great impact is the first report of a 'Candidatus Phytoplasma phoenicium'-related strain in Canada, while 'Ca. P. pruni' and 'Ca. P. pyri' were reported for the first time in eastern Canada. These findings will have a great impact on the management of phytoplasmas and their insect vectors. Using these insect-vectored bacterial pathogens, we show the need for new strategies that can allow fast and accurate communication between concerned citizens and those institutions confirming their observations.[Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Asunto(s)
Ciencia Ciudadana , Phytoplasma , Phytoplasma/genética , Canadá
4.
Plant Dis ; 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-36973911

RESUMEN

Alstroemeria necrotic streak virus (ANSV) is an Orthotospovirus that has been isolated from symptomatic Alstroemeria plant in 2010 (Hassani-Mehraban et al. 2010). It has been shown to infect crops of bell pepper (Capsicum annuum) and tomato (Solanum lycopersicum) (Olaya et al. 2017) which are two of the three biggest greenhouse crops in Canada in terms of production volume and value (Statistic Canada. 2020). In July of 2022, the entire production of bell pepper (all plants) from a greenhouse in Québec was presenting necrotic rings and discoloration in fruit and seemingly healthy leaves. Samples from these infected bell pepper were found to be negative for twenty two common viruses infecting bell pepper by ELISA immunoassay by the Laboratoire d'expertise et de diagnostic en phytoprotection (LEDP) (Québec, Canada). To identify the causal agent, double-stranded RNA was extracted from leaf and fruit of one plant to form two separate samples (leaf and fruit) and used for cDNA library preparations with Nextera XT DNA Sample Prep kit (Illumina, USA). The libraries were sequenced using Illumina Miseq (Fall et al. 2020). The same dsRNA were also sequenced with MinION nanopore sequencing method as described previously (Javaran et al. 2021; Javaran et al. 2023). The obtained raw FASTQ data were processed following the methodology described in Fall et al. 2020 and Javaran et al. 2023. The Miseq sequencing yielded over 2 million reads per sample with a percentage of mapped viral reads ranging from 26.92 to 47.29% of the total number of reads. The leaf samples were positive to Bell pepper endornavirus (BPEV) with the full genome covered 16713 times and Alstroemeria necrotic streak virus (ANSV) with 98% of the genome covered 4929 times. The MinION sequencing yielded 1,028,460 reads and the same viruses were detected with 1288 long reads (mean length of 745bp) assigned to ANSV genome. Both viruses were detected in the leaf and fruit samples. The complete ANSV genome comprising three segments (L, M, and S) was assembled and deposited in GenBank: (OQ261731-OQ261733). These L, M and S segments shown 99% nt identity with an isolate from the Columbia (GenBank: MF469036, MF469037, MF469038). It is interesting that read coverage at near the 2000th position of the S segment, was very low. This phenomenon may suggest a cleavage site nearby by a viral or host factor. ANSV was mainly found in leaf samples and very low numbers of reads in fruit samples. The presence of ANSV was confirmed by RT-PCR using the primers specific to the ANSV nucleocapsid gene Tospo_S_F (5'- CAG AAT CAG GCT GCA TTT AAT TTC C-3') and Tospo_S_R (5'-CAA CGC TTC CTT TAG CAT TAG G-3') (Gallo et al. 2019). The sequences of ∼600 bp amplicons were determined using Sanger sequencing and showed 100% nt identity with Miseq-derived sequences of ANSV. The virus has previously been detected in Colombia (Hassani-Mehraban et al. 2010) and then in California in 2018 (Tian et al. 2020). This is to our knowledge the first detection of ANSV in Canada. Bell pepper is one of the most important crops in Canada and the ANSV vector, the western flower thrips (Frankliniella occidentalis), known to spread the tomato spotted wilt virus (TSWV) is established in Canada (Allen et al. 1986). The detection of ANSV in Canada is line with the hypothesis of an international spread of this virus (Tian et al. 2020) as is it not known to spread through seeds.

5.
J Water Health ; 20(11): 1654-1667, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36448615

RESUMEN

Diarrheal diseases are the second leading cause of child mortality worldwide, occurring in about one in every nine child deaths, and were associated with water, sanitation, and hygiene (WASH) access. In this study, we provided an overview of WASH indicators' evolution from 2000 to 2017 and their impact on the occurrence of diarrhea in children under 5 years old in Senegal. It was a retrospective cross-sectional study, in which we did a secondary analysis of data from the Joint Monitoring Program (JMP) for water supply and sanitation and from the Senegal Demographic and Health Survey 2018. Our results showed that access to safely managed services increased by 18.1 and 19.1%, respectively, for water and sanitation. The prevalence of diarrhea estimated at 18.16% was associated with straining water through a cloth (adjusted odds ratio (AOR) [95% confidence interval (CI)]: 1.21 [1.00-1.45]) and getting water supplies from a source not located in a dwelling (AOR [95% CI]: 1.59 [1.21-2.09]). The prevalence of diarrhea among children under 5 years old was still relatively high in Senegal and was significantly associated with a lack of WASH access. Although the latter continues to increase, additional efforts to make water safer to drink will significantly reduce the occurrence of diarrheal diseases among children under 5 years old in Senegal.


Asunto(s)
Higiene , Saneamiento , Niño , Humanos , Preescolar , Estudios Transversales , Estudios Retrospectivos , Senegal/epidemiología , Diarrea/epidemiología
6.
BMC Public Health ; 22(1): 2327, 2022 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-36510195

RESUMEN

BACKGROUND: One out of ten deaths of children under five are attributable to indoor air pollution. And Acute Respiratory Illness (ARI) is among the direct causes. OBJECTIVE: This study showed the possibilities of characterizing indoor air pollution in West African Economic and Monetary Union (WAEMU) area and it also made it possible to estimate its impact on the occurrence of ARI in children under five. METHODS: It has been a secondary analysis based on Demographic and Health Surveys (DHSs) from WAEMU countries' data.. "Household level of air pollution" is the created composite variable, from questions on the degradation factors of indoor air quality (domestic combustion processes) which served to characterize indoor air pollution and to measure its impact by a logistic regression. RESULTS: Burkina Faso stands out with a greater number of households with a high level of pollution (63.7%) followed by Benin (43.7%) then Togo (43.0%). The main exposure factor "Household level of air pollution" was associated with ARI symptoms (Togo: prevalence = 51.3%; chi-squared test's p-value < 0.001). Exposure to high level of pollution constitutes a risk (AOR [95 CI]), even though it is not significant ( Ivory Coast: 1.29 [0.72-2.30], Senegal: 1.39 [0.94-2.05] and Togo: 1.15 [0.67-1.95]) and this could be explained by the high infectious etiology of the ARI.


Asunto(s)
Contaminación del Aire Interior , Contaminación del Aire , Infecciones del Sistema Respiratorio , Niño , Humanos , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/etiología , Factores de Riesgo , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Contaminación del Aire Interior/efectos adversos , Contaminación del Aire Interior/análisis , Prevalencia , Burkina Faso , Culinaria
7.
Plant Dis ; 106(11): 2866-2875, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35536207

RESUMEN

There is evidence of five clades of Plasmopara viticola in the world. Only two clades, riparia and aestivalis, have been identified as responsible for downy mildew epidemics in Quebec, Canada. It was reported in 2021 that epidemics caused by clade riparia start 2 or 3 weeks before those caused by clade aestivalis and that clade aestivalis was more aggressive than clade riparia. The objective of this work was to study the competition between P. viticola clade riparia (A) and clade aestivalis (B) and to compare the aggressiveness of both clades in mono- and coinfection situations. Suspensions of sporangia from both clades with six percentage combinations (AB 100-0; AB 89-11; AB 74-26; AB 46-54; AB 23-77; and AB 0-100) were inoculated on leaf discs (cultivar Vidal), and three other combinations (AB 88-12; AB 68-32; and AB 47-53) were inoculated on living leaves of grape plants (cultivar Vidal). Then, sporangium production, expressed as the percentage of sporangia produced by each clade, was estimated on leaf discs after eight cycles of infection-sporulation and then validated on living grape leaves after five cycles. The aggressiveness of clades in monoinfection situations on leaf discs was compared with that in coinfection situations. The results show that the percentage of sporangia produced by clade aestivalis increases with the infection-sporulation cycle while that produced by clade riparia decreases. The area under the sporangium production progress curve (AUSPPC) of clade aestivalis was significantly higher than that of clade riparia. The aggressiveness of P. viticola clades riparia and aestivalis in coinfection situations was different from that in monoinfection situations and was strongly influenced by the percentage of each clade in competition. These results suggest that, on the grapevine cultivar Vidal, P. viticola clade aestivalis is more competitive than clade riparia and that the percentage of each clade present in the vineyard should be considered for management of downy mildew.[Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.


Asunto(s)
Coinfección , Oomicetos , Peronospora , Vitis , Enfermedades de las Plantas , Oomicetos/genética , Peronospora/genética
8.
Environ Monit Assess ; 195(1): 185, 2022 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-36482211

RESUMEN

Marine pollution in West Africa is major threat particularly around coastal megacities. We assess the chemical and ecotoxicological quality of the marine sediments in various submerged sampling sites of Dakar. Analysis revealed that sediments were slightly basic in which fine and coarse sands predominated. High percentages of total organic carbon were found sometime above 6%. Higher levels of heavy metal were reported than in previous studies. Chromium and nickel were above the Probable Effect Concentration. Low trophic level appeared not affected by the overall toxicity, while medium trophic level was more affected. Indeed, the vast majority (91%) of sites studied revealed a net percentage of Magallana gigas embryolarval developmental abnormality over 20%. The assessment of the global toxicity of marine sediments from the Dakar sites Studied (n = 11) seemed, almost, as a whole, to be in a poor ecotoxicological state calling to take measures to improve the sanitary condition of this marine feature.


Asunto(s)
Ecotoxicología , Monitoreo del Ambiente , Senegal , África Occidental
9.
Plant Dis ; 2021 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-34096765

RESUMEN

Quebec is the third largest wine grape producer in Canada in acreage, tonnage, and wine grape sales (Carisse et al. 2017; Ben Moussa et al. 2019). To evaluate the diversity of viruses infecting grapevine in Quebec, a total of 77 leaf tissue samples (cv. Vidal) were collected from July to October in 2020 in three different vineyards located in Frelighsburg, Hemmingford and Saint-Jacques-le-Mineur in Quebec, Canada. Double-stranded RNA was extracted from each sample and used for cDNA library preparation with the Nextera XT DNA Library Preparation Kit (Illumina) as described previously (Kesanakurti et al. 2016). High-throughput sequencing (HTS, 2x300 bp) was conducted on dual-indexed libraries in a v3 flow cell using the Illumina MiSeq platform (Adkar-Purushothama et al. 2020). The obtained raw FASTQ data was de-multiplexed into 154 separate sequence files, and the adapters and barcode sequences were trimmed. The quality of the sequences was verified using Trimmomatic V.0.32 and the "clean" sequences were analyzed using Virtool and VirFind virus detection pipelines described elsewhere (Ho and Tzanetakis 2014; Rott et al. 2017) to screen for all possible viruses in the databases. Over 100,000 reads per sample were obtained with a percentage of mapped viral reads ranging from 1.47 to 19.43% of total number of reads. Out of 77 samples, 16 revealed the sequence of grapevine yellow speckle viroid 1 (GYSVd-1), for which the length coverage ranged from 98.5 to 99.1%; the depth ranged from 2X to 856X. The GYSVd-1 positive sequence files were subjected to whole genome assembly on CLC genomics Workbench v20.0.4 with the isolate SY-BR from Brazil (KU880715) used as reference. Seven complete genomes of GYSVd-1 of 366-368 nucleotides (nt) in size were deposited (GenBank Acc. MW732682 to MW732688). BLASTN analysis of the sequences showed 98-100% nt identities with isolate SY-BR. Other viruses and viroids such as Grapevine fleck virus, Grapevine rupestris stem pitting-associated virus, Grapevine rupestris vein feathering virus and Hop stunt viroid were also detected. To confirm GYSVd-1 presence in Quebec vineyards, seven of the 16 HTS-positive grapevine leaf tissue samples were subjected to total RNA extraction, followed by RT-PCR assay as before (Adkar-Purushothama et al. 2015; Sahana et al. 2013); all were positive by RT-PCR. The PCR products were directly Sanger-sequenced, and they showed 100% nt identity to the HTS derived sequences. Three of the seven GYSVd-1 positive grapevines exhibited yellow leaf spots and flecks and tiny yellow leaves, but their mixed infection status makes definitive symptoms association difficult to determine. Previously, Hop stunt viroid was reported from grapevines in Canada (Xiao et al. 2019; Fall et al. 2020) but to the best of our knowledge, this is the first report of GYSVd-1 infecting grapevines in Canada, specifically in the province of Quebec. Further research is required to assess the GYSVd-1 related yield loss. Monitoring and testing for GYSVd-1 infection is necessary to prevent propagation of infected materials, spread, and potential negative impact for the Canadian grapevine industry.

10.
J Environ Manage ; 269: 110772, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32560993

RESUMEN

In this research, the effect of curing temperature on the metalloid (As) leachability of cemented paste backfill (CPB; a mix of tailings, cement and water) is studied. ASTM C 1308 leaching protocol is used to determine the leachability of CPB samples subjected to different curing temperatures (2, 20 and 35 °C). In addition, the effect of curing temperature on the microstructure of CPB is assessed to determine if the temperature dependence of the leaching characteristics of CPB is related to variations in the microstructure of the cement matrix. The microstructural techniques used include, powder x-ray diffraction, mercury intrusion porosimetry, and scanning electron microscopy techniques. The results obtained indicate that the curing temperature has a significant effect on the leachability of CPB. It is found that as curing temperature increased from 2 °C to 35 °C the performance of the CPB for arsenic immobilization decreased. The magnitude of this temperature-induced change in As-leachability of CPB depends on the curing temperature range (low (≤20 °C) or elevated (35 °C) temperatures). This curing temperature dependency of the leachability of CPB is attributable to the temperature-induced changes in the pore structure of CPB, formation/development of hydration products and pH in the CPBs during the curing process. The results also indicate that diffusion dominates as the leaching mechanism through the studied temperature range and is independent of curing temperature. However, curing temperature does control the availability for arsenic to leach. The new findings presented in this paper will contribute to design more environmental-friendly cemented paste backfill materials and structures, which is vital for sustainable mining.


Asunto(s)
Arsénico , Materiales de Construcción , Minería , Sulfuros , Temperatura
11.
Phytopathology ; 109(7): 1157-1170, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30860431

RESUMEN

As complete host resistance in soybean has not been achieved, Sclerotinia stem rot (SSR) caused by Sclerotinia sclerotiorum continues to be of major economic concern for farmers. Thus, chemical control remains a prevalent disease management strategy. Pesticide evaluations were conducted in Illinois, Iowa, Michigan, Minnesota, New Jersey, and Wisconsin from 2009 to 2016, for a total of 25 site-years (n = 2,057 plot-level data points). These studies were used in network meta-analyses to evaluate the impact of 10 popular pesticide active ingredients, and seven common application timings on SSR control and yield benefit, compared with not treating with a pesticide. Boscalid and picoxystrobin frequently offered the best reductions in disease severity and best yield benefit (P < 0.0001). Pesticide applications (one- or two-spray programs) made during the bloom period provided significant reductions in disease severity index (DIX) (P < 0.0001) and led to significant yield benefits (P = 0.0009). Data from these studies were also used in nonlinear regression analyses to determine the effect of DIX on soybean yield. A three-parameter logistic model was found to best describe soybean yield loss (pseudo-R2 = 0.309). In modern soybean cultivars, yield loss due to SSR does not occur until 20 to 25% DIX, and considerable yield loss (-697 kg ha-1 or -10 bu acre-1) is observed at 68% DIX. Further analyses identified several pesticides and programs that resulted in greater than 60% probability for return on investment under high disease levels.


Asunto(s)
Ascomicetos , Glycine max/crecimiento & desarrollo , Plaguicidas , Ascomicetos/crecimiento & desarrollo , Illinois , Iowa , Michigan , Minnesota , Enfermedades de las Plantas/microbiología , Wisconsin
12.
Phytopathology ; 108(4): 469-478, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29231778

RESUMEN

Sclerotinia sclerotiorum is a significant threat to soybean production worldwide. In this study, an epidemiological approach was used to examine 11 years of historical data from a soybean management performance trial in order to advance our understanding of Sclerotinia stem rot (SSR) development and to identify environmental predictors of SSR epidemics and associated yield losses. Recursive partitioning analysis suggested that average air temperature and total precipitation in July were the most significant variables associated with disease severity. High levels of SSR disease severity index were observed when the average temperature in July was below 19.5°C and total precipitation in July was moderate, between 20 and 108.5 mm. A biphasic sigmoidal curve accurately described the relationship between SSR disease severity index (DSI) and yield, with a DSI threshold of 22, below which minimal yield loss was observed. A 10% increase in the DSI, from 22.0 to 24.2, led to an 11% decrease in yield, from 3,308.14 to 2,951.29 kg/ha. Also, a yield threshold (3,353 kg/ha) that was higher than the annual U.S. average soybean yield (3,039.7 kg/ha) was suggested as an expected yield under low or no SSR pressure in the U.S. Midwest. These thresholds can allow soybean stakeholders to assess the value of disease control and establish an SSR baseline for cost-effective management to protect yields. Because S. sclerotiorum has more than 400 plant host species, and because having quantitative information concerning crop losses is crucial for decision making, this study shows the usefulness of historical data on SSR and, hence, can serve as a model in other SSR pathosystems (canola, dry bean, potato, pea, and so on).


Asunto(s)
Ascomicetos/fisiología , Glycine max/microbiología , Modelos Estadísticos , Enfermedades de las Plantas/estadística & datos numéricos , Modelos Logísticos , Enfermedades de las Plantas/microbiología , Tallos de la Planta/crecimiento & desarrollo , Tallos de la Planta/microbiología , Riesgo , Glycine max/crecimiento & desarrollo , Tiempo (Meteorología)
13.
Plant Dis ; 102(1): 73-84, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30673449

RESUMEN

Sclerotinia stem rot (SSR) epidemics in soybean, caused by Sclerotinia sclerotiorum, are currently responsible for annual yield reductions in the United States of up to 1 million metric tons. In-season disease management is largely dependent on chemical control but its efficiency and cost-effectiveness depends on both the chemistry used and the risk of apothecia formation, germination, and further dispersal of ascospores during susceptible soybean growth stages. Hence, accurate prediction of the S. sclerotiorum apothecial risk during the soybean flowering period could enable farmers to improve in-season SSR management. From 2014 to 2016, apothecial presence or absence was monitored in three irrigated (n = 1,505 plot-level observations) and six nonirrigated (n = 2,361 plot-level observations) field trials located in Iowa (n = 156), Michigan (n = 1,400), and Wisconsin (n = 2,310), for a total of 3,866 plot-level observations. Hourly air temperature, relative humidity, dew point, wind speed, leaf wetness, and rainfall were also monitored continuously, throughout the season, at each location using high-resolution gridded weather data. Logistic regression models were developed for irrigated and nonirrigated conditions using apothecial presence as a binary response variable. Agronomic variables (row width) and weather-related variables (defined as 30-day moving averages, prior to apothecial presence) were tested for their predictive ability. In irrigated soybean fields, apothecial presence was best explained by row width (r = -0.41, P < 0.0001), 30-day moving averages of daily maximum air temperature (r = 0.27, P < 0.0001), and daily maximum relative humidity (r = 0.16, P < 0.05). In nonirrigated fields, apothecial presence was best explained by using moving averages of daily maximum air temperature (r = -0.30, P < 0.0001) and wind speed (r = -0.27, P < 0.0001). These models correctly predicted (overall accuracy of 67 to 70%) apothecial presence during the soybean flowering period for four independent datasets (n = 1,102 plot-level observations or 30 daily mean observations).


Asunto(s)
Ascomicetos/fisiología , Producción de Cultivos/métodos , Glycine max , Enfermedades de las Plantas/microbiología , Tiempo (Meteorología) , Ascomicetos/crecimiento & desarrollo , Iowa , Modelos Logísticos , Michigan , Riesgo , Glycine max/crecimiento & desarrollo , Esporas Fúngicas/fisiología , Wisconsin
14.
Plant Dis ; 102(12): 2592-2601, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30334675

RESUMEN

In soybean, Sclerotinia sclerotiorum apothecia are the sources of primary inoculum (ascospores) critical for Sclerotinia stem rot (SSR) development. We recently developed logistic regression models to predict the presence of apothecia in irrigated and nonirrigated soybean fields. In 2017, small-plot trials were established to validate two weather-based models (one for irrigated fields and one for nonirrigated fields) to predict SSR development. Additionally, apothecial scouting and disease monitoring were conducted in 60 commercial fields in three states between 2016 and 2017 to evaluate model accuracy across the growing region. Site-specific air temperature, relative humidity, and wind speed data were obtained through the Integrated Pest Information Platform for Extension and Education (iPiPE) and Dark Sky weather networks. Across all locations, iPiPE-driven model predictions during the soybean flowering period (R1 to R4 growth stages) explained end-of-season disease observations with an accuracy of 81.8% using a probability action threshold of 35%. Dark Sky data, incorporating bias corrections for weather variables, explained end-of-season disease observations with 87.9% accuracy (in 2017 commercial locations in Wisconsin) using a 40% probability threshold. Overall, these validations indicate that these two weather-based apothecial models, using either weather data source, provide disease risk predictions that both reduce unnecessary chemical application and accurately advise applications at critical times.


Asunto(s)
Ascomicetos/fisiología , Fungicidas Industriales/farmacología , Glycine max/microbiología , Enfermedades de las Plantas/estadística & datos numéricos , Algoritmos , Ascomicetos/efectos de los fármacos , Flores/microbiología , Cuerpos Fructíferos de los Hongos , Modelos Logísticos , Enfermedades de las Plantas/microbiología , Análisis de Regresión , Esporas Fúngicas , Tiempo (Meteorología) , Wisconsin
15.
Environ Sci Pollut Res Int ; 31(10): 14894-14911, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38286929

RESUMEN

Given that many mines around the world are located in areas where fresh water is scarce, and companies are being held to increasingly stringent sustainability and environmental responsibility standards, many mines are looking to use locally available saline groundwater or seawater as mixing water in cemented paste backfill (CPB). However, the impacts of this decision on key engineering properties of CPB (e.g. strength and self-desiccation) that affect its mechanical stability need to be better understood to allow confident selection of this practical and more sustainable solution. Thus, the effect of mixing water salinity and binder type on the strength (unconfined compressive strength, UCS) development and self-desiccation (measured by suction and volumetric water content) of CPB is explored in this research. NaCl concentrations from 0 to 300 g/L were used in CPB made with silica tailings and Portland cement type I (PC). Concentrations of 10 and 35 g/L were found to moderately increase UCS, while a concentration of 100 g/L had comparable UCS to non-saline CPB and a concentration of 300 g/L was found to significantly decrease UCS over all curing times. The overall trend is 10 g/L > 35 g/L > 0 g/L > 100 g/L > 300 g/L. The UCS of the 60-day-old CPB with a NaCl of 300 g/L is significantly lower, registering a 26% decrease compared to the UCS of the 60-day-old CPB without salt. In contrast, the UCS of the 60-day-old CPBs containing 10 g/L and 35 g/L of salt exhibits a notable improvement, being 15% and 10% higher, respectively, than the UCS of the 60-day-old CPB without salt. Water content and suction monitoring were conducted up to 28 days of curing time, and it was found that suction only slightly contributed to UCS gain of the saline CPB, and high salt contents (100 and 300 g/L) significantly inhibited the self-desiccation ability of CPB due to inhibition of cement hydration by the excessive amount of salt. The increase in strength of both saline and non-saline samples was attributed primarily to the increase in cement hydration products, while the increased strength of the samples with salinities of 10 and 35 g/L was mainly attributed to the enhancement of the binder hydration due to the low amount of salt and the presence of Friedel's salt in the pores. The effect of PC replacement by 25 to 75% with slag on CPB with 35 g/L mixing water salinity was also studied. Slag replacement of 50% and higher resulted in significantly higher UCS over most curing times. Suction likely moderately contributed to UCS of the saline CPB with slag, in addition to the presence of Friedel's salt in the pores and the acceleration of cement and slag hydration by the presence of NaCl.


Asunto(s)
Óxido de Aluminio , Cloruro de Calcio , Desecación , Cloruro de Sodio , Materiales de Construcción , Agua , Cloruro de Sodio Dietético
16.
J Virol Methods ; 329: 114997, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39059502

RESUMEN

The extraction of double stranded (ds) RNA is a common enrichment method for the study, characterization, and detection of RNA viruses. In addition to RNA viruses, viroids, and some DNA viruses, can also be detected from dsRNA enriched extracts which makes it an attractive method for detecting a wide range of viruses when coupled with HTS. Several dsRNA enrichment strategies have been developed. The oldest utilizes the selective binding properties of dsRNA to cellulose. More recent methods are based on the application of anti-dsRNA antibodies and viral proteins with a specific affinity for dsRNA. All three methods have been used together with HTS for plant virus detection and study. To our knowledge, this is the first comparative study of three alternative dsRNA enrichment methods for virus and viroid detection through HTS using virus-infected, and healthy grapevine test plants. Extracts were performed in triplicate using methods based on, the anti-dsRNA antibody mAb rJ2 (Millipore Sigma Canada Ltd, Oakville, ON, Canada), the B2 dsRNA binding protein, and ReliaPrep™ Resin (Promega Corporation, Madison, WI, USA). The results show that the workflows for all three methods are effectively comparable, apart from purification steps related to antibody and binding protein construct. Both the cellulose resin and dsRNA binding protein construct methods provide highly enriched dsRNA extracts suitable for HTS with the B2 method providing a 36× and the ReliaPrep™ Resin a 163× increase in dsRNA enrichment compared to the mAb rJ2 antibody. The overall consistency and cost effectiveness of the ReliaPrep™ cellulose resin-based method and the potentially simpler adaptation to robotics made it the method of choice for future transfer to a semi-automated workflow.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento , Enfermedades de las Plantas , ARN Bicatenario , ARN Viral , Vitis , ARN Bicatenario/genética , Vitis/virología , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , ARN Viral/genética , Enfermedades de las Plantas/virología , Virus de Plantas/genética , Virus de Plantas/aislamiento & purificación , Virus ARN/genética , Virus ARN/aislamiento & purificación
17.
Sante Publique ; 25(1): 69-76, 2013.
Artículo en Francés | MEDLINE | ID: mdl-23705337

RESUMEN

AIM: Since 1968, the World Health Organization has used an international pharmacovigilance programme to monitor and examine the effects of drugs. The purpose of this study was to assess the knowledge and attitudes of dentists toward pharmacovigilance. METHODS: The paper presents the results of a cross-sectional descriptive study of 103 dentists in Senegal, based on an exhaustive selection process. Data were collected on the dentists' sociodemographic characteristics and their knowledge and attitudes toward pharmacovigilance. RESULTS: Over 50% of the sample were general practitioners. The average number of years of professional experience was 9 years. Painkillers (41.9%) were the most widely prescribed drugs, followed by antibiotics, which were particularly involved in the onset of adverse effects (41.8%). Adverse effects were observed by just 3.8% of the sample. Almost 90% of the participants were not aware of the existing pharmacovigilance system. CONCLUSION: The results suggest that pharmacovigilance training and education sessions for dentists are needed to improve their knowledge of pharmacovigilance and to foster positive attitudes toward adverse effects.


Asunto(s)
Actitud del Personal de Salud , Odontología , Odontólogos , Conocimientos, Actitudes y Práctica en Salud , Farmacovigilancia , Pautas de la Práctica en Medicina , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Senegal , Encuestas y Cuestionarios
18.
Front Microbiol ; 14: 1192781, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37415816

RESUMEN

There is a global need for identifying viral pathogens, as well as for providing certified clean plant materials, in order to limit the spread of viral diseases. A key component of management programs for viral-like diseases is having a diagnostic tool that is quick, reliable, inexpensive, and easy to use. We have developed and validated a dsRNA-based nanopore sequencing protocol as a reliable method for detecting viruses and viroids in grapevines. We compared our method, which we term direct-cDNA sequencing from dsRNA (dsRNAcD), to direct RNA sequencing from rRNA-depleted total RNA (rdTotalRNA), and found that it provided more viral reads from infected samples. Indeed, dsRNAcD was able to detect all of the viruses and viroids detected using Illumina MiSeq sequencing (dsRNA-MiSeq). Furthermore, dsRNAcD sequencing was also able to detect low-abundance viruses that rdTotalRNA sequencing failed to detect. Additionally, rdTotalRNA sequencing resulted in a false-positive viroid identification due to the misannotation of a host-driven read. Two taxonomic classification workflows, DIAMOND & MEGAN (DIA & MEG) and Centrifuge & Recentrifuge (Cent & Rec), were also evaluated for quick and accurate read classification. Although the results from both workflows were similar, we identified pros and cons for both workflows. Our study shows that dsRNAcD sequencing and the proposed data analysis workflows are suitable for consistent detection of viruses and viroids, particularly in grapevines where mixed viral infections are common.

19.
Viruses ; 15(3)2023 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-36992444

RESUMEN

This study investigated the phylogenetic relationship of grapevine Pinot gris virus (GPGV) isolates from Canada with GPGV isolates reported worldwide. Full-length genomes of 25 GPGV isolates representing the main four grape-growing regions in Canada (British Columbia, Ontario, Nova Scotia and Quebec) were sequenced and compared to genomes of 43 GPGV isolates representing eight countries and three continents. Phylogenetic analysis based on full genome sequences revealed an unambiguous separation of North American GPGV isolates with isolates from Europe and Asia. Within the North American clade, GPGV isolates from the USA segregated into a distinct subclade, whereas the relationships amongst GPGV isolates from different regions of Canada were not clearly defined. The phylogenetic analysis of the overlapping regions of MP and CP genes involving 169 isolates from 14 countries resulted in two distinctive clades, which were seemingly independent of their country of origin. Clade 1 included the majority of asymptomatic isolates (81% asymptomatic), whereas clade 2 was predominantly formed of symptomatic isolates (78% symptomatic). This research is the first study focused on the genetic variability and origin of GPGV in Canada.


Asunto(s)
Flexiviridae , Vitis , Filogenia , Flexiviridae/genética , Genoma Viral , Ontario
20.
Environ Sci Pollut Res Int ; 29(18): 26285-26296, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34851486

RESUMEN

In Senegal, processes employed for recycling e-wastes result in release of so-called heavy metals in the environment. In this study, the metal distribution and concentrations of soils collected from four e-waste recycling areas located in the Dakar area are presented. Measurements are performed using portable X-ray fluorescence and laser-induced breakdown spectroscopy (LIBS) to obtain a complete analysis of the soil, including major and trace elements (i.e., mg/kg). Levels of zinc, copper, manganese, and iron in soils are high but contrasted ranging from 66 mg/kg for Cu in Mbeubeuss landfill to more than 1000 mg/kg for Mn and 10,000 mg/kg for Zn. Lower values are obtained for chromium and lead (Cr = 207 mg/kg and Pb = 181 mg/kg). The most elevated average lead values (i.e., 2935 mg/kg and 1427 mg/kg) are obtained from the e-waste recycling sites located in the urban area of Dakar: Reubeuss and Pikine, respectively. Specific element fingerprints are obtained from each of the studied areas. To evaluate human exposure to the main metals, vegetables grown outside the large e-waste landfill were analyzed. The values obtained for Cr, Cu, Fe, Mn, Sr, and Zn are low, ranging from 0.11 to 9.66 mg/kg for chromium in turnip and iron in beetroots, respectively. The calculated health risk index remains below unit for all vegetables, which means no potential risk of vegetable consumption for human health. The data provided useful information to estimate contaminations and their origin. Therefore, in order to ensure food safety, continuous monitoring of the vegetables grown in the vicinity of recycling areas is needed.


Asunto(s)
Residuos Electrónicos , Metales Pesados , Contaminantes del Suelo , Cromo/análisis , Residuos Electrónicos/análisis , Monitoreo del Ambiente/métodos , Contaminación de Alimentos/análisis , Humanos , Hierro/análisis , Metales Pesados/análisis , Reciclaje , Senegal , Suelo/química , Contaminantes del Suelo/análisis , Verduras/química
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA