Daily and seasonal dynamics of airborne spores of Fusarium graminearum and other Fusarium species sampled over wheat plots

2000 ◽  
Vol 78 (4) ◽  
pp. 497-505 ◽  
Author(s):  
W GD Fernando ◽  
J D Miller ◽  
W L Seaman ◽  
K Seifert ◽  
T C Paulitz
Keyword(s):  
Fusarium Graminearum ◽  
Fusarium Species ◽  
Sampling Period ◽  
Gibberella Zeae ◽  
Spore Density ◽  
Airborne Spores ◽  
Rainfall Events ◽  
Spore Release ◽  
Daily Sampling ◽  
Order Of Magnitude

Spores were sampled during 2 years over wheat plots at Ottawa, Ontario. Plots were treated with corn colonized with Gibberella zeae (Schwein.) Petch (anamorph Fusarium graminearum Schwabe). In 1994, viable spores were sampled with four Burkard high-throughput jet samplers. Gibberella zeae ascospores were recovered mostly at night and showed four main release events during the 20-day sampling period, 1-3 days after rain events. Highest density of G. zeae spores (1500 spores/m3) were sampled 1.5 m away from the inoculum source, with fewer spores 5 m away. Recovery of otherFusarium species was sporadic. For all species, there were no statistical differences among the daily sampling times, although for most species, morning counts were the lowest. Other Fusarium species detected, in decreasing order of spore density, were F. crookwellense, F. sporotrichioides, F. moniliforme, F. equiseti, F. subglutinans, and F. culmorum. Most spore release events did not correlate with rainfall events. In 1995, a Burkard continuous 7-day spore sampler was used to investigate the release of ascospores and macroconidia of G. zeae. Ascospores, but not macroconidia, showed a daily periodicity. Daily average densities of macroconidia were an order of magnitude less than ascospores. Ascospore release was correlated with rainfall events and the time of day.Key words: spore sampling,Gibberella zeae, Fusarium graminearum, Fusarium sp. ascospores, macroconidia.

Fusarium species and mycotoxins associated with oat in southwestern Ontario, Canada

2010 ◽  
Vol 90 (2) ◽  
pp. 211-216 ◽  
Author(s):  
L. Tamburic-Ilincic
Keyword(s):  
Fusarium Graminearum ◽  
Avena Sativa ◽  
Fusarium Species ◽  
Gibberella Zeae ◽  
Fusarium Sporotrichioides ◽  
Fusarium Spp ◽  
Predominant Species ◽  
Spray Inoculation ◽  
Growing Conditions ◽  
Performance Trial

Fusarium graminearum Schwabe [teleomorph: Gibberella zeae Schwein. Petch] is the predominant Fusarium species pathogenic to wheat, barley and corn in Ontario and produces the mycotoxin deoxynivalenol (DON) in grain. The first objective of this study was to determine the Fusarium spp. and mycotoxin concentrations (DON, HT-2, and T-2) from commercial oat (Avena sativa L.) fields grown in the same area as wheat, corn and barley in Ontario. The second objective was to measure DON level across cultivars grown in the Ontario Performance Trial (OPT) after spray-inoculation with F. graminearum. Fusarium sporotrichioides, F. graminearum and F. poae were the predominant species identified in oat. The highest level of DON in commercial oat fields were 0.3, 0.1, 0.2 and 1.2 ppm in 2005, 2006, 2007 and 2008, respectively. The highest concentrations of HT-2, and T-2 in 2006 were 0.5 and 0.2 ppm, respectively, whereas the levels in 2007 were both under 0.2 ppm. The relatively low level of DON in commercial oat fields confirmed that oat is in general less affected with F. graminearum than other cereals. However, this study supports the importance of monitoring Fusarium spp. and concentrations of mycotoxins in oat in Ontario, especially during growing conditions, as experienced in 2008, which favored Fusarium infection and DON accumulation. Differences in percent of Fusarium spp. infected kernels and DON level (ppm) were identified amongst the cultivars in the OPT in naturally infected oat samples and after inoculation, respectively. Key words: Oat, Fusarium spp., mycotoxins

scholarly journals Fusarium Head Blight Inoculum: Species Prevalence and Gibberella zeae Spore Type

Plant Disease ◽  
2003 ◽  
Vol 87 (7) ◽  
pp. 814-820 ◽  
Author(s):  
S. G. Markell ◽  
L. J. Francl
Keyword(s):  
Fusarium Species ◽  
Selective Medium ◽  
Gibberella Zeae ◽  
Head Blight ◽  
Field Bioassay ◽  
Airborne Spores ◽  
Growing Seasons ◽  
Field Environment ◽  
Potted Plant ◽  
Bioassay Technique

The objectives of this study were to examine the relative abundance of Gibberella zeae ascospores and conidia and other Fusarium species on wheat spikes in a field environment, to relate inoculum counts of G. zeae to airborne spore counts, and to evaluate an inoculum bioassay technique. The inoculum levels of Fusarium species and airborne spores of G. zeae were measured in North Dakota during the 1999, 2000, and 2001 growing seasons. Spores were collected from wheat spikes in a 24-h potted-plant bioassay in a fallowed field and in a spring wheat plot bioassay. Inoculum levels of Fusarium species were assessed by placing a solution recovered from bioassays on selective medium; meanwhile, ascospores and conidia of G. zeae were enumerated microscopically. A Burkard cyclonic sampler measured airborne spore levels in the fallowed field. Wheat spikes were inoculated with known concentrations of conidia or ascospores, and rinsate was put on selective medium at different intervals to compare recovery rates. Known concentrations of both spore types were also applied directly to selective medium to compare with recovery of spore types from inoculated spikes. Fusarium graminearum was the most prevalent Fusarium species on wheat spikes, although F. moniliforme and F. poae counts were highest on some days. Approximately twice as many ascospores were recovered in both the 24-h potted-plant field bioassay and the cyclonic sampler as were conidia. Significantly more colonies were recovered from wheat spikes after conidial inoculation than after ascospore inoculation at an identical concentration regardless of time of rinsate collection. Colony numbers did not differ significantly following application of ascospores and conidia to selective medium. Results confirm the predominance of G. zeae inoculum in North America but indicate conidia play an important role in the primary disease cycle.

scholarly journals Técnicas de aplicação de fungicida em trigo para o controle de Giberela (Gibberella zeae)

2003 ◽  
Vol 33 (1) ◽  
pp. 13-20 ◽  
Author(s):  
Edivan Panisson ◽  
Walter Boller ◽  
Erlei Melo Reis ◽  
Laércio Hoffmann
Keyword(s):  
Fusarium Graminearum ◽  
Gibberella Zeae

Durante muitos anos, a giberela, causada pelo fungo Gibberella zeae (anamorfo Fusarium graminearum), foi considerada de importância secundária no sul do Brasil. O aumento da intensidade e da freqüência de ocorrência, tornou a giberela uma das doenças de maior importância na cultura do trigo. A giberela é uma doença de infecção floral e mesmo os fungicidas sistêmicos recomendados apresentam apenas efeito protetor das anteras. Os objetivos do presente trabalho foram avaliar a eficiência de controle e os efeitos nos grãos colhidos, de dois tipos de pontas de pulverização (leque e duplo leque), diferentes arranjos dos bicos na barra de aplicação e dois volumes de calda. A desuniformidade da antese aparece como um dos principais fatores envolvidos com a baixa eficiência dos fungicidas. Nos experimentos, realizados no ano 2000, a aplicação dos tratamentos reduziu significativamente a incidência, o número de espiguetas gibereladas e a severidade da doença, aumentando o rendimento de grãos. As pontas de pulverização, seus arranjos na barra e os volumes de calda utilizados comportaram-se de maneira semelhante em todas as variáveis avaliadas. O incremento no rendimento de grãos, obtido em relação à testemunha, sugere que se deve recomendar a aplicação de fungicidas para o controle da giberela, utilizando pontas que geram gotas finas a médias com volume de calda de 200 L.ha-1.

Physiological and Environmental Aspects of Ascospore Discharge in Gibberella zeae (Anamorph Fusarium graminearum)

Mycologia ◽  
2002 ◽  
Vol 94 (2) ◽  
pp. 181 ◽  
Author(s):  
Frances Trail ◽  
Haixin Xu ◽  
Rachel Loranger ◽  
David Gadoury
Keyword(s):  
Fusarium Graminearum ◽  
Gibberella Zeae ◽  
Environmental Aspects ◽  
Ascospore Discharge

scholarly journals Rain Splash Dispersal of Gibberella zeae Within Wheat Canopies in Ohio

2004 ◽  
Vol 94 (12) ◽  
pp. 1342-1349 ◽  
Author(s):  
P. A. Paul ◽  
S. M. El-Allaf ◽  
P. E. Lipps ◽  
L. V. Madden
Keyword(s):  
Flux Density ◽  
Soil Surface ◽  
Selective Medium ◽  
Gibberella Zeae ◽  
Spore Density ◽  
Rain Intensity ◽  
Head Blight ◽  
Splash Dispersal ◽  
Rain Splash ◽  
Maize Kernels

Rain splash dispersal of Gibberella zeae, causal agent of Fusarium head blight of wheat, was investigated in field studies in Ohio between 2001 and 2003. Samplers placed at 0, 30, and 100 cm above the soil surface were used to collect rain splash in wheat fields with maize residue on the surface and fields with G. zeae-infested maize kernels. Rain splash was collected during separate rain episodes throughout the wheat-growing seasons. Aliquots of splashed rain were transferred to petri dishes containing Komada's selective medium, and G. zeae was identified based on colony and spore morphology. Dispersed spores were measured in CFU/ml. Intensity of splashed rain was highest at 100 cm and ranged from 0.2 to 10.2 mm h-1, depending on incident rain intensity and sampler height. Spores were recovered from splash samples at all heights in both locations for all sampled rain events. Both macroconidia and ascospores were found based on microscopic examination of random samples of splashed rain. Spore density and spore flux density per rain episode ranged from 0.4 to 40.9 CFU cm-2 and 0.4 to 84.8 CFU cm-2 h-1, respectively. Spore flux density was higher in fields with G. zeae-infested maize kernels than in fields with maize debris, and generally was higher at 0 and 30 cm than at 100 cm at both locations. However, on average, spore flux density was only 30% lower at 100 cm (height of wheat spikes) than at the other heights. The log of spore flux density was linearly related to the log of splashed rain intensity and the log of incident rain intensity. The regression slopes were not significantly affected by year, location, height, and their interactions, but the intercepts were significantly affected by both sampler height and location. Thus, our results show that spores of G. zeae were consistently splash dispersed to spike heights within wheat canopies, and splashed rain intensity and spore flux density could be predicted based on incident rain intensity in order to estimate inoculum dispersal within the wheat canopy.

scholarly journals The Spread of a Released Clone of Gibberella zeae from Different Amounts of Infested Corn Residue

Plant Disease ◽  
2011 ◽  
Vol 95 (11) ◽  
pp. 1458-1464 ◽  
Author(s):  
Melissa D. Keller ◽  
Wade E. Thomason ◽  
David G. Schmale
Keyword(s):  
Fusarium Graminearum ◽  
Wheat Cultivar ◽  
Gibberella Zeae ◽  
Corn Stalk ◽  
Head Blight ◽  
Inoculum Sources ◽  
Length Polymorphisms ◽  
Amplified Fragment Length Polymorphisms ◽  
Corn Residue ◽  
Moderately Resistant

Corn residue is a significant source of inoculum for epidemics of Fusarium head blight (FHB) in wheat and barley, but little is known about the influence of different amounts of corn residue on FHB. We monitored the spread of a released clone of Gibberella zeae (Fusarium graminearum), causal agent of FHB, from small 0.84-m-diameter research plots containing 45, 200, or 410 g of infested corn stalk pieces in winter wheat and barley fields in Virginia over 3 years (2008 to 2010). The fungus was recaptured through the collection of wheat and barley spikes at 0 and 3 m from the source and the released clone was identified in heterogeneous background populations using amplified fragment length polymorphisms. Results showed a slightly greater intensity of recovery of the clone at a greater distance when more infested residue was present. Plots containing larger amounts of inoculum (410 g) generally resulted in a smaller decline of recovery of the clone at 3 m from the source, indicating a greater spread from the larger inoculum source. The clone was also recovered at distances ≥18 m from inoculum sources. Larger amounts of corn residue generally had less influence on clone recovery in plots containing a moderately resistant wheat cultivar than those containing a susceptible wheat cultivar.

Relation of weather variables and host factors to incidence of airborne spores of Bipolaris sorokiniana

1978 ◽  
Vol 56 (17) ◽  
pp. 2162-2170 ◽  
Author(s):  
L. Couture ◽  
J. C. Sutton
Keyword(s):  
High Temperatures ◽  
Bipolaris Sorokiniana ◽  
Weather Variables ◽  
Weather Factors ◽  
Airborne Spores ◽  
Surface Wetness ◽  
Large Numbers ◽  
Spore Release ◽  
Crop Development ◽  
Field Plots

Seasonal and daily incidence of airborne spores of Bipolaris sorokiniana were studied in barley field plots in relation to crop development, disease severity, and weather variables. Sporulation was observed only on dead or senescent barley. The incidence of airborne spores before 8–11 July was low because spore-bearing barley foliage was scarce and weather factors were often unfavourable for sporulation. Large numbers of spores encountered after 8–11 July coincided with rapid disease progress and repeated occurrence of persistent leaf wetness and high temperatures. Cumulative spore counts showed that few spores were dispersed sufficiently early in the growing season to serve as inoculum in the epidemics. Numbers of airborne spores were low at night, but increased abruptly after dawn to peak concentrations during 0900 to 1700 hours. Circumstantial evidence indicated that spore production was promoted by persistent leaf-surface wetness, high relative humidity (RH), and high temperatures (> 15 °C), but restricted by cool temperatures. Correlative studies showed that spore release was caused by rapidly declining RH and wind. Spores were dispersed mostly when the leaves were dry and the numbers dispersed correlated very strongly with wind speed. Few spores were dispersed when leaves were wet and RH high.

Gene expression shifts during perithecium development in Gibberella zeae (anamorph Fusarium graminearum), with particular emphasis on ion transport proteins

2007 ◽  
Vol 44 (11) ◽  
pp. 1146-1156 ◽  
Author(s):  
Heather E. Hallen ◽  
Marianne Huebner ◽  
Shin-Han Shiu ◽  
Ulrich Güldener ◽  
Frances Trail
Keyword(s):  
Gene Expression ◽  
Ion Transport ◽  
Fusarium Graminearum ◽  
Transport Proteins ◽  
Gibberella Zeae

scholarly journals Dispersal Distances for Airborne Spores Based on Deposition Rates and Stochastic Modeling

2007 ◽  
Vol 97 (10) ◽  
pp. 1325-1330 ◽  
Author(s):  
Anders Stockmarr ◽  
Viggo Andreasen ◽  
Hanne Østergård
Keyword(s):  
Fungal Spores ◽  
Two Dimensional ◽  
Airborne Spores ◽  
Modeling Framework ◽  
Deposition Rates ◽  
Spore Release ◽  
Special Cases ◽  
Release Height ◽  
Dispersal Distances ◽  
Parameter Values

A new modeling framework for particle dispersal is explored in the context of the particles being fungal spores dispersed within a field. The model gives rise to both exponentially decreasing and polynomially decreasing two-dimensional densities of deposited fungal spores. We reformulate the model in terms of time to deposition, and show how this concept is equivalent to the deposition rate for fungal spores. Special cases where parameter values for wind and gravitation lead to exponentially or polynomially decreasing densities are discussed, and formulas for one- and two-dimensional densities of deposited spores are given explicitly in terms of parameters for diffusion, wind, gravitation, and spore release height.

Sign in / Sign up

Export Citation Format

Share Document