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X.-M. Xu,
D. W. Parry,
P. Nicholson,
M. A. Thomsett,
D. Simpson,
S. G. Edwards, B. M. Cooke,
F. M. Doohan,
S. Monaghan,
A. Moretti,
G. Tocco,
G. Mule,
L. Hornok,
E. Béki,
J. Tatnell,
A. Ritieni
[show abstract]
[hide abstract]
ABSTRACT: Within-field variability in the Fusarium head blight (FHB) and its associated mycotoxins was studied in four European countries.
At each of 14 sites, each FHB pathogen and associated mycotoxins were quantified in 16 quadrat samples at harvest. Overall,
the incidence of quadrat samples with detectable and quantifiable pathogen DNA was significantly lower in the grain than in
the corresponding chaff. Deoxynivalenol (DON) was the most frequently detected toxin in the samples and its accumulation was
most strongly associated with the presence of Fusarium graminearum. Nivalenol (NIV) accumulation was significantly associated only with the presence of F. culmorum. Zearalenone (ZON) accumulation was strongly associated with the presence of all three pathogens (F. graminearum, F. culmorum and F. poae). The levels of both DON and ZON concentrations were positively related to the amount of F. graminearum DNA in the grain or in the chaff. The presence/absence of FHB pathogens within a single quadrat appeared to be independent
of each other. The presence of a particular FHB pathogen and the amount of its DNA, as well as the associated mycotoxin(s),
varied greatly among samples at each site. This study demonstrated the large extent of within-field variability of FHB and
its associated mycotoxins, and the importance of representative sampling in FHB studies.
European Journal of Plant Pathology 04/2012; 120(1):21-34. · 1.41 Impact Factor
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X-M Xu,
P Nicholson,
M A Thomsett,
D Simpson, B M Cooke,
F M Doohan,
J Brennan,
S Monaghan,
A Moretti,
G Mule,
L Hornok,
E Beki,
J Tatnell,
A Ritieni,
S G Edwards
[show abstract]
[hide abstract]
ABSTRACT: ABSTRACT Over 4 years, the environmental conditions and the causal agents of Fusarium head blight (FHB) disease of wheat were determined in field sites in four European countries: Hungary, Ireland, Italy, and the United Kingdom. Polymerase chain reaction-based methods were used to detect each species causing FHB and quantify its DNA (as a measurement of fungal abundance) in the samples. Canonical correspondence analysis (CCA) was used to determine the relationship of the incidence and abundance of each species with weather variables. CCA indicated that little variability in the species prevalence data was explained by the weather variables. In contrast, a greater proportion of variability in abundance data was accounted for by the weather variables. Most samples contained two or more species and statistical analysis suggested that these species tended to coexist at field sites. CCA also indicated that there were differences in the relationships of the prevalence and abundance of the six FHB species with environmental variables. Fusarium poae was associated with relatively drier and warmer conditions, whereas F. graminearum was associated with warmer/humid conditions. F. avenaceum and F. culmorum were both associated with niches of cooler/wet/humid conditions. Two Microdochium species were associated with regions of relatively cool/moderate temperatures and frequent rainfalls of short duration. The results also suggested that environmental conditions differentially affect the infection and colonization processes, and the comparative abundance of the six species.
Phytopathology 02/2008; 98(1):69-78. · 2.80 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: Susceptibility of eight commercial European wheat cultivars to fusarium head blight (FHB) disease caused by Fusarium graminearum, F. culmorum, F. poae and Microdochium nivale (formerly known as Fusarium nivale) was compared under controlled environment conditions (16°C). FHB did not differentially affect cultivars in terms of disease symptoms, fungal DNA content of grain or deoxynivalenol (DON) contamination. However, the Hungarian-grown cultivars GK-Othalom and Fatima 2 (of Romanian origin) showed greater type V resistance (yield tolerance) to FHB than did the others. Also, nivalenol was produced by F. poae in these two cultivars and in Italian cultivar Norba, but not in other cultivars. Overall, significant relationships were found between the FHB and seedling blight resistance in vitro of these eight cultivars, but such relationships were generally highly dependent on cultivar, and therefore it is likely that the in vitro test is at best measuring components of FHB resistance and/or genotype-specific resistance components.
Plant Pathology 10/2006; 56(1):55 - 64. · 2.13 Impact Factor
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Xiangming Xu,
D. W. Parry,
P. Nicholson,
M. A. Thomsett,
D. Simpson,
S. G. Edwards, B. M. Cooke,
F. M. Doohan,
J. M. Brennan,
A. Moretti,
G. Tocco,
G. Mule,
L. Hornok,
G. Giczey,
J. Tatnell
[show abstract]
[hide abstract]
ABSTRACT: Two years of field sampling aimed to establish the predominance and association among the fungal pathogens causing Fusarium ear blight (FEB) in four European countries (Hungary, Ireland, Italy and the UK). A PCR-based method was used to detect four Fusarium species and two varieties of Microdochium nivale present in the samples. The prevalence of FEB pathogens differed significantly between countries. Overall, all pathogens were commonly detected in Ireland and to a lesser extent in the UK. In contrast, only two species, F. graminearum and F. poae, were regularly detected in Italy and Hungary. Fusarium culmorum was rarely detected except in Ireland. Log-linear models were used to determine whether there is the independence of the six FEB pathogens at each sampling site. Significant two-pathogen interactions were frequently observed, particularly in harvest samples; all these significant two-pathogen interactions were of the synergistic type, except between F. poae and F. culmorum, and were generally consistent over the 2 years and four countries. Fusarium graminearum and F. poae were least frequently involved in two pathogen interactions but were involved in most of the nine significant three-pathogen interactions. However, only the interaction between F. graminearum, F. avenaceum and F. poae was significant in both years. Potential implications of the present results in FEB management are discussed.
European Journal of Plant Pathology 05/2005; 112(2):143-154. · 1.41 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: This research examined the variation in the response of eight commercial wheat cultivars to Microdochium nivale isolates using both in vivo FHB tests (AUDPC and RHW measurements) and in vitro detached leaf assays (LGR). Irrespective of fungal variety, the two Italian cvs Fortore and Norba exhibited the greatest amount of visual disease symptoms (mean AUDPC=2.2 and 2.3, respectively), being significantly more susceptible than the other six cultivars (AUDPC 1.24) (P < 0.05).="" irrespective="" of="" fungal="" variety,="" the="" italian="" cv.="" norba="" and="" the="" irish="" cv.="" falstaff="" were="" more="" susceptible="" than="" the="" other="" cultivars="" (except="" fatima="" 2)="" in="" terms="" of="" rhw="">P < 0.05),="" while="" the="" cvs="" fortore,="" gk="" othalom="" and="" consort="" were="" more="" resistant="" than="" the="" other="" five="" cultivars="">P < 0.05).="" in="" the="" detached="" leaf="" assay,="" the="" hungarian="" cv.="" gk="" othalom="" and="" the="" italian="" cv.="" norba="" were="" more="" susceptible="" (mean="" lgr="0.79" and="" 0.81mm="">–1, respectively) to M. nivalethan the other six cultivars (mean LGR=0.51–0.72) (P < 0.05).="" analysis="" of="" the="" relationship="" between="" head="" and="" leaf="" reaction="" to="">M. nivaleinfection revealed no significant correlation.
European Journal of Plant Pathology 04/2005; 112(1):79-83. · 1.41 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: The effect of small temperature differentials (16 vs. 20°C) on the pathogenicity of deoxynivalenol producing single isolates of Fusarium culmorum and F. graminearum and on the fusarium head blight (FHB) response of eight wheat cultivars was examined. Fusarium culmorum inoculation caused greater visual disease symptoms at 20°C than at 16°C, both overall and on an individual cultivar basis (overall AUDPC = 13·5 and 9·6, respectively) (P < 0·05). In contrast, F. graminearum inoculation caused greater overall visual disease symptoms at 16°C than at 20°C, both overall and at the individual cultivar level (overall AUDPC = 12·8 and 10·9, respectively) (P < 0·05). Results showed both F. culmorum and F. graminearum inoculations caused a greater loss in yield at 20°C (54·3 and 46·9% relative 1000-grain weight, respectively) compared with 16°C (73·3 and 66·9% relative 1000-grain weight, respectively) (P < 0·05). Fusarium culmorum-inoculated heads contained similar amounts of fungal DNA at both 16 and 20°C (1·9 and 1·7 ng mg−1 of plant material, respectively) (not significant), while for F. graminearum inoculation, plants contained higher amounts of fungal DNA at 20°C (2·0 and 1·0 ng mg−1 of plant material, respectively) (P < 0·05). Overall, there was a significant negative correlation between AUDPC and percentage relative 1000-grain weight at both 16 and 20°C (r =−0·693 and −0·794, respectively, P < 0·01).
Plant Pathology 03/2005; 54(2):156 - 160. · 2.13 Impact Factor
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X.-m. Xu,
D.W. Parry,
S.G. Edwards, B.M. Cooke,
F.M. Doohan,
A. Maanen,
J.M. Brennan,
S. Monaghan,
A. Moretti,
G. Tocco,
G. Mule,
L. Hornok,
G. Giczey,
J. Tatnell,
P. Nicholson,
A. Ritieni
[show abstract]
[hide abstract]
ABSTRACT: There is a urgent need to develop a rational strategy for managing Fusarium ear blight in order to reduce current reliance on routine fungicide applications, based on an objective assessment of disease risks. One of important components for such a management strategy is a fast, easy, accurate and reliable method for disease assessment. The relationship between incidence of Fusarium ear blight ear infection and number of spikelets infected on an ear (or incidence of spikelet infection) were investigated during three seasons and in four countries in order to derive a simple relationship for predicting disease at the spikelet level using ear incidence. More than half of the data sets of the number of infected spikelets on an ear could not be fitted satisfactorily by a Poisson distribution. Three two-parameter discrete distributions (negative binominal, Neyman type A and Polya-Aeppli) provided a significantly better fit than the Poisson distribution, indicating a degree of aggregation of number of infected spikelets on an ear. Taylor''s power-law satisfactorily described the observed variance–mean relationship for the number of infected spikelets on an ear; this relationship was generally consistent over years and countries. A robust relationship between incidence of ear infection and average number of infected spikelets per ear was obtained assuming a fixed variance–mean relationship and a negative binomial distribution for the number of infected spikelets. A relationship between incidences of spikelet and ear infection was also obtained based on the complementary log–log or logit transformation of ear and spikelet infection incidence. These models appeared to be consistent over years and countries and thus may be used in making practical disease management decisions involving fungicide applications.
European Journal of Plant Pathology 10/2004; 110(9):959-971. · 1.41 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: The effect of temperature on the in vitro growth rates and pathogenicity of a European Fusarium collection consisting of isolates of Fusarium graminearum,
F. culmorum,
F. avenaceum, F. poae and Microdochium nivale was examined. Irrespective of geographic origin, the optimum temperature for the growth of F. graminearum, F. culmorum and F. poae was 25 C, while that for F. avenaceum and M. nivale was 20 C. In general, the growth rates of F. graminearum, F. culmorum and F. poae increased between 10 and 25 C and those of F. avenaceum and M. nivale increased between 10 and 20 C. Pathogenicity tests were carried out by examining the effect of the five species on the in vitro coleoptile growth rate of wheat seedlings (cv. Falstaff). Irrespective of geographic origin, the temperature at which F. avenaceum, F. culmorum and F. graminearum caused the greatest retardation in coleoptile growth ranges 20–25 C (>89.3% reduction), whilst for F. poae and M. nivale it was 10–15 C (>45.6% retardation), relative to uninoculated control seedlings. In general, F. culmorum and F. graminearum were the most pathogenic of the five species, causing at least a 69% reduction in coleoptile growth at 10, 15, 20 and 25 C. General linear model analysis (GLIM) showed that species accounted for 51.3–63.4% of the variation in isolate growth and from 19.5% to 44.3% of the variation in in vitro pathogenicity. Country of origin contributed from 22.6% to 51.9% to growth rate variation and from 0.73% to 7.61% to pathogenicity variation. The only significant correlation between in vitro growth and pathogenicity was that observed for M. nivale at 15 C (r = -0.803, P
European Journal of Plant Pathology 06/2003; 109(6):577-587. · 1.41 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: Fusarium head blight of small-grain cereals, ear rot of maize, seedling blight and foot rot of cereals are important diseases throughout the world. Fusarium graminearum, F. culmorum, F. poae, F. avenaceum and Microdochium nivale (formerly known as F. nivale) predominantly cause Fusarium diseases of small-grain cereals. Maize is predominantly attacked by F. graminearum, F. moniliforme, F. proliferatum and F. subglutinans. These species differ in their climatic distribution and in the optimum climatic conditions required for their persistence. This review deals with the influence of climate on the production and dispersal of inocula, growth, competition, mycotoxin production and pathogenicity. Most species produce inocula, grow best, and are most pathogenic to cereal heads at warm temperatures and under humid conditions. However, the optimal conditions for F. moniliforme and F. proliferatum maize ear rot tend to be hot and dry and M. nivale head blight, seedling blight and foot rot of small-grain cereals tend to occur under cooler conditions. Seedling blight and foot rot caused by other species are favoured by warm dry weather. Between them, these fungi produce four important classes of mycotoxins: trichothecenes, zearalenone, fumonisins and moniliformin. Conditions favourable for in vitro growth are also generally the most favourable for mycotoxin production on cereal grains. These fungi rarely exist in isolation, but occur as a complex with each other and with other Fusaria and other fungal genera. Climatic conditions will influence competition between, and the predominance of, different fungi within this complex.
European Journal of Plant Pathology 01/2003; 109(7):755-768. · 1.41 Impact Factor
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Xiangming Xu,
D. W. Parry,
S. G. Edwards, B. M. Cooke,
F. M. Doohan,
A. van Maanen,
J. M. Brennan,
S. Monaghan,
A. Moretti,
G. Tocco,
G. Mule,
L. Hornok,
G. Giczey,
J. Tatnell,
P. Nicholson,
A. Ritieni
[show abstract]
[hide abstract]
ABSTRACT: There is a urgent need to develop a rational strategy for managing Fusarium ear blight in order to reduce current reliance on routine fungicide applications, based on an objective assessment of disease risks. One of important components for such a management strategy is a fast, easy, accurate and reliable method for disease assessment. The relationship between incidence of Fusarium ear blight ear infection and number of spikelets infected on an ear ( or incidence of spikelet infection) were investigated during three seasons and in four countries in order to derive a simple relationship for predicting disease at the spikelet level using ear incidence. More than half of the data sets of the number of infected spikelets on an ear could not be fitted satisfactorily by a Poisson distribution. Three two-parameter discrete distributions (negative binominal, Neyman type A and Polya-Aeppli) provided a significantly better fit than the Poisson distribution, indicating a degree of aggregation of number of infected spikelets on an ear. Taylor's power-law satisfactorily described the observed variance-mean relationship for the number of infected spikelets on an ear; this relationship was generally consistent over years and countries. A robust relationship between incidence of ear infection and average number of infected spikelets per ear was obtained assuming a fixed variance mean relationship and a negative binomial distribution for the number of infected spikelets. A relationship between incidences of spikelet and ear infection was also obtained based on the complementary log-log or logit transformation of ear and spikelet infection incidence. These models appeared to be consistent over years and countries and thus may be used in making practical disease management decisions involving fungicide applications.
European Journal of Plant Pathology. 110(9):959-971.
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Xiangming Xu,
P. Nicholson,
M. A. Thomsett,
D. Simpson, B. M. Cooke,
F. M. Doohan,
J. Brennan,
S. Monaghan,
A. Moretti,
G. Mule,
L. Homok,
E. Beki,
J. Tatnell,
A. Ritieni,
S. G. Edwards
[show abstract]
[hide abstract]
ABSTRACT: Over 4 years, the environmental conditions and the causal agents of Fusarium head blight (FHB) disease of wheat were determined in field sites in four European countries: Hungary, Ireland, Italy, and the United Kingdom. Polymerase chain reaction-based methods were used to detect each species causing FHB and quantify its DNA (as a measurement of fungal abundance) in the samples. Canonical correspondence analysis (CCA) was used to determine the relationship of the incidence and abundance of each species with weather variables. CCA indicated that little variability in the species prevalence data was explained by the weather variables. In contrast, a greater proportion of variability in abundance data was accounted for by the weather variables. Most samples contained two or more species and statistical analysis suggested that these species tended to coexist at field sites. CCA also indicated that there were differences in the relationships of the prevalence and abundance of the six FHB species with environmental variables. Fusarium poae was associated with relatively drier and warmer conditions, whereas F. graminearum was associated with warmer/humid conditions. F. avenaceum and F. culmorum were both associated with niches of cooler/wet/humid conditions. Two Microdochium species were associated with regions of relatively cool/moderate temperatures and frequent rainfalls of short duration. The results also suggested that environmental conditions differentially affect the infection and colonization processes, and the comparative abundance of the six species.
Phytopathology. 98(1):69-78.
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X. M. Xu,
D. W. Parry,
P. Nicholson,
M. A. Thomsett,
D. Simpson,
S. G. Edwards, B. M. Cooke,
F. Doohan,
A. van Maanen,
A. Moretti,
G. Tocco,
G. Mule,
L. Hornok,
G. Giczey,
J. Tatnell,
A. Ritieni
[show abstract]
[hide abstract]
ABSTRACT: This paper reports the results of field sampling in 2001 aimed at establishing the relationship between the incidence of Fusarium ear blight (FEB; Fusarium culmorum, F. graminearum [ Gibberella zeae], Microdochium nivale [ Monographella nivalis], F. avenaceum [ Gibberella avenacea] and F. poae), the biomass (DNA) of the associated Fusarium species and the accumulation of related mycotoxins in wheat grains from UK, Irish Republic, Italy and Hungary. The prevalence of Fusarium species as well as the FEB incidence and the resulting mycotoxins varied with the country. For almost all of the sites where mycotoxins (deoxynivalenol [vomitoxin], nivalenol and zearalenone) were detected, the levels were very low and negligible. Deoxynivalenol was the most common toxin detected, while beauvericin, fusaproliferin and enniatins were not detected in any samples. There appears to be no quantitative relationship between the amount of Fusarium DNA and the concentration of mycotoxins in the grain.
Aspects of Applied Biology.
