Field testing of antagonists of Fusarium head blight incited by Gibberella zeae

2004 ◽  
Vol 29 (2) ◽  
pp. 245-255 ◽  
Author(s):  
N.I Khan ◽  
D.A Schisler ◽  
M.J Boehm ◽  
P.E Lipps ◽  
P.J Slininger
Author(s):  
Hussein M. Khaeim ◽  
Anthony Clark ◽  
Tom Pearson ◽  
Dr. David Van Sanford

Head scab is historically a devastating disease affecting not just all classes of wheat but also barley and other small grains around the world. Fusarium head blight (FHB), or head scab, is caused most often by Fusarium graminearum (Schwabe), (sexual stage – Gibberella zeae) although several Fusarium spp. can cause the disease. This study was conducted to determine the effect of mass selection for FHB resistance using an image-based optical sorter. lines were derived from the C0 and C2 of two populations to compare genetic variation within populations with and without sorter selection. Our overall hypothesis is that sorting grain results in improved Fusarium head blight resistance. Both of the used wheat derived line populations have genetic variation, and population 1 has more than population 17. They are significantly different from each other for fusarium damged kernel (FDK), deoxynivalenol (DON), and other FHB traits. Although both populations are suitable to be grown for bulks, population 1 seems better since it has more genetic variation as well as lower FDK and DON, and earlier heading date. Lines within each population were significantly different and some lines in each population had significantly lower FDK and DON after selection using an optical sorter. Some lines had significant reduction in both FDK and DON, and some others had either FDK or DON reduction. Lines of population 1 that had significant reduction, were more numerous than in population 17, and FDK and DON reduction were greater.


Plant Disease ◽  
2021 ◽  
Author(s):  
Bhavit Chhabra ◽  
Lovepreet Singh ◽  
Sydney Wallace ◽  
Adam Schoen ◽  
Yanhong Dong ◽  
...  

Fusarium head blight (FHB) primarily caused by Fusarium graminearum is a key disease of small grains. Diseased spikes show symptoms of premature bleaching shortly after infection and have aborted or shriveled seeds, resulting in reduced yields. The fungus also deteriorates quality and safety of the grain due to production of mycotoxins, especially deoxynivalenol (DON), which can result in grain being docked or rejected at the point of sale. Genetic host resistance to FHB is quantitative and no complete genetic resistance against this devastating disease is available. Alternative approaches to develop new sources of FHB resistance are needed. In this study, we performed extensive forward genetic screening of the M4 generation of an EMS induced mutagenized population of cultivar Jagger to isolate variants with FHB resistance. In field testing, 74 mutant lines were found to have resistance against FHB spread and 30 lines out of these also had low DON content. Subsequent testing over two years in controlled greenhouse conditions revealed ten M6 lines showing significantly lower FHB spread. Seven and six lines out of those 10 lines also had reduced DON content and lower FDKs, respectively. Future endeavors will include identification of the mutations that led to resistance in these variants.


2016 ◽  
Vol 42 (2) ◽  
pp. 134-139 ◽  
Author(s):  
Erlei Melo Reis ◽  
Cristina Boareto ◽  
Anderson Luiz Durante Danelli ◽  
Sandra Maria Zoldan

ABSTRACT Fusarium head blight of wheat (Triticum aestivum), caused by the fungus Gibberella zeae, is a floral infecting disease that causes quantitative and qualitative losses to winter cereals. In Brazil, the sanitary situation of wheat has led to research in order to develop strategies for sustainable production, even under adverse weather conditions. To increase the knowledge of the relationship among the presence of anthesis, the infectious process, the disease progress and the saprophytic fungi present in wheat anthers, studies were conducted in the experimental field of University of Passo Fundo (UPF), using the cultivar Marfim, in the 2011 growing season. The disease incidence in spikes and spikelets was evaluated. The presence of exserted anthers increased the spike exposure time to the inoculum. The final incidence of fusarium head blight, in the field, was dependent on the presence of exserted anthers. The disease followed an aggregation pattern and its evolution increased with time, apparently showing growth according to secondary cycles. The fungi isolated from exserted anthers (Alternaria sp., Fusarium sp., Drechslera spp. and Epicoccum sp.) did not compete for the infection site of fusarium head blight in wheat, not interfering with the incidence of F. graminearum.


2020 ◽  
Author(s):  
John E McLaughlin ◽  
Noura Al Darwish ◽  
Jeffrey Garcia-Sanchez ◽  
Neerja Tyagi ◽  
Harold N Trick ◽  
...  

Trichothecene mycotoxins such as deoxynivalenol (DON), are virulence factors of Fusarium graminearum, which causes Fusarium head blight (FHB), one of the most important diseases of small grain cereals. We previously identified a non-specific lipid transfer protein (nsLTP) gene, AtLTP4.4, which was overexpressed in an activation tagged Arabidopsis line resistant to trichothecin (Tcin), a type B trichothecene in the same class as DON. Here we show that overexpression of AtLTP4.4 in transgenic wheat significantly reduced F. graminearum growth in Bobwhite and RB07 lines in the greenhouse and reduced fungal lesion size in detached leaf assays. Hydrogen peroxide accumulation was attenuated upon exposure of transgenic wheat plants to DON, indicating that AtLTP4.4 may confer resistance by inhibiting oxidative stress. Field testing indicated that disease severity was significantly reduced in two transgenic Bobwhite lines expressing AtLTP4.4. DON accumulation was significantly reduced in four different transgenic Bobwhite lines expressing AtLTP4.4 or a wheat nsLTP, TaLTP3, which was previously shown to have antioxidant activity. Recombinant AtLTP4.4 purified from Pichia pastoris exhibited potent antifungal activity against F. graminearum. These results demonstrate that overexpression of AtLTP4.4 in transgenic wheat suppresses DON accumulation in the field. Suppression of DON induced reactive oxygen species by AtLTP4.4 might be the mechanism by which fungal spread and mycotoxin accumulation are inhibited in the transgenic wheat plants.


2009 ◽  
Vol 2 (2) ◽  
pp. 193-201 ◽  
Author(s):  
A. Xue ◽  
H. Voldeng ◽  
M. Savard ◽  
G. Fedak

Fusarium head blight (FHB), caused by Gibberella zeae is a harmful disease of wheat. To manage FHB and mycotoxin contamination in wheat, field experiments were conducted from 2007 to 2008 to evaluate a total of 20 selected bioagents for their ability to inhibit perithecial production of G. zeae and for the control of FHB and deoxynivalenol (DON) contamination, in comparison with the registered fungicide Folicur (tebuconazole). All 20 bioagents significantly reduced the perithecial production compared to the untreated control. Clonostachy rosea strain ACM941 was the most effective treatment, reducing the production of perithecia by 63.7% in 2007 and 67.5% in 2008. These effects were significantly better than Folicur fungicide, which reduced perithecial production by 30.4% and 20.5%, for 2007 and 2008, respectively. When sprayed on to wheat heads, seven of the 20 bioagents significantly reduced the FHB index, one reduced Fusarium damaged kernels (FDK), and six reduced DON content in grains in 2007. ACM941 was the only treatment that significantly reduced FHB index, FDK, and DON, by 46.4%, 29.0% and 28.7%, respectively. Among the six bioagents and three formulated products evaluated in two separate field trials in 2008, ACM941 and its formulated product ACM941-CU were the only treatments that significantly reduced FHB index, FDK, and DON. The treatments reduced FHB index by 30.8% and 31.4%, FDK by 17.8% and 43.8%, and DON by 30.8% and 37.1%, for ACM941 and ACM941-CU, respectively. These effects were less marked than those of the Folicur fungicide that reduced FHB index by 98.8%, FDK by 94.2%, and DON by 92.1%. Results of this study suggest that ACM941 is a promising bioagent against G. zeae and may be used as a control measure in organic farming and in an integrated FHB and DON management program for wheat production.


2012 ◽  
Vol 5 (1) ◽  
pp. 45-55 ◽  
Author(s):  
P. Gautam ◽  
R. Dill-Macky

Fusarium graminearum Schwabe [teleomorph Gibberella zeae (Schwein) Petch] is the predominant causal agent of Fusarium head blight (FHB), an economically important disease of wheat, in North America. Warm and humid environments at and shortly after anthesis favour FHB. FHB results in yield losses and quality losses in infected grain due to the accumulation of mycotoxins produced by the invading fungus. The objective of this study was to characterise the influence of different F. graminearum isolates and host resistance on FHB development and mycotoxin accumulation. A series of two greenhouse experiments were established where five single isolates of F. graminearum were tested. Three wheat cultivars were examined: Alsen (moderately resistant), 2375 (moderately susceptible) and Wheaton (susceptible). In the point-inoculation experiments, ca. 1000 conidia were placed into a central spikelet of spikes at anthesis. Point-inoculated spikelets were sampled at different growth stages up to soft dough stage. Samples from both experiment series were analysed for mycotoxins. The susceptible cultivar Wheaton had both the highest FHB severity and mycotoxin accumulation. The spread of symptoms both below and above the inoculated central spikelet was significantly higher in 2375 and Wheaton than Alsen. Though deoxynivalenol (DON) did not peak and decline in all experiments, when a peak in the DON content was present it was earlier in 2375 (early milk) than in either Alsen (early dough) or Wheaton (late milk). Though the isolates did not rank similarly in all experiments and in all cultivars, generally isolates Butte86Ada-11 and B63A were more aggressive and isolates 49-3 and B45A were less aggressive in terms of disease severity and mycotoxin accumulation.


1997 ◽  
Vol 87 (4) ◽  
pp. 414-421 ◽  
Author(s):  
W. G. D. Fernando ◽  
T. C. Paulitz ◽  
W. L. Seaman ◽  
P. Dutilleul ◽  
J. D. Miller

The spread of Fusarium head blight of wheat from a small area inoculum source was examined in wheat plots (100, 625, or 2,500 m2) inoculated in the center with Gibberella zeae-colonized corn kernels or macro-conidia sprayed on heads at anthesis. With the first inoculation method, disease foci were produced from ascospores released from perithecia formed on inoculated kernels. With the second inoculation method, disease foci were produced by macroconidia directly applied to the heads. Some plots were misted during anthesis. Plots were divided into grids, and disease incidence on spikelets and seeds was assessed at the grid intersections. Isopath contour maps were constructed using an interpolation procedure based on a weighted least squares method. Disease gradients were constructed from the isopath contours in the direction parallel to average nightly wind vectors using an exponential model. This study was conducted over a 3-year period at two sites: one in Quebec and one in Ontario. Both inoculation methods resulted in a discrete, primary focus of head blight in each plot, with one or two smaller secondary foci in some plots. The highest incidence of disease on spikelets or seed was commonly displaced somewhat from the inoculum source, usually downwind. The gradient slopes of seed and spikelet infection ranged from −0.10 to −0.43 m−1 in plots with ascospore inoculum and from −0.48 to −0.79 m−1 in plots inoculated with macroconidia. Seed infection declined to 10% of the maximum within 5 to 22 m from the focal center in asco-spore-inoculated plots, and within 5 m in a macroconidia-inoculated plot. Gradients were usually steeper upwind compared with downwind of the inoculum source. In misted plots, incidence of disease was higher and more diffuse than in nonirrigated plots. Based on gradients and dispersal patterns, disease foci in plots inoculated with G. zeae-colonized corn kernels probably arose from airborne ascospores rather than from splash-borne macroconidia and were the result of infection events that occurred over a short period of time. Comparison of conidial- and ascospore-derived disease gradients indicated a lack of secondary infection, confirming that Fusarium head blight is primarily a monocyclic disease.


Plant Disease ◽  
2012 ◽  
Vol 96 (5) ◽  
pp. 673-680 ◽  
Author(s):  
K. D. Bondalapati ◽  
J. M. Stein ◽  
S. M. Neate ◽  
S. H. Halley ◽  
L. E. Osborne ◽  
...  

The associations between Fusarium head blight (FHB), caused by Gibberella zeae, and deoxynivalenol (DON) accumulation in spring malting barley (Hordeum vulgare) and hourly weather conditions predictive of DON accumulation were examined using data from six growing seasons in the U.S. Northern Great Plains. Three commonly grown cultivars were planted throughout the region, and FHB disease and DON concentration were recorded. Nine predictor variables were calculated using hourly temperature and relative humidity during the 10 days preceding full head spike emergence. Simple logistic regression models were developed using these predictor variables based on a binary threshold for DON of 0.5 mg/kg. Four of the nine models had sensitivity greater than 80%, and specificity of these models ranged from 67 to 84% (n = 150). The most useful predictor was the joint effect of average hourly temperature and a weighted duration of uninterrupted hours (h) with relative humidity greater than or equal to 90%. The results of this study confirm that FHB incidence is significantly associated with DON accumulation in the grain and that weather conditions prior to full head emergence could be used to accurately predict the risk of economically significant DON accumulation for spring malting barley.


Plant Disease ◽  
2008 ◽  
Vol 92 (5) ◽  
pp. 800-807 ◽  
Author(s):  
S. A. Pereyra ◽  
R. Dill-Macky

The presence of Fusarium spp. was examined in the residues of wheat, barley, corn, sunflower, pasture, and gramineous weed species common in wheat and barley cropping systems collected from no-tillage and reduced-tillage plots from February 2001 to March 2003 in Uruguay. Gibberella zeae was recovered from residues of wheat, barley, corn, sunflower, fescue, and the gramineous weeds Digitaria sanguinalis, Setaria spp., Lolium multiflorum, and Cynodon dactylon, except from birdsfoot trefoil or white clover. Of the Fusarium spp. obtained, G. zeae was the most frequently recovered from wheat and barley residues, while other species were more common in other crops. G. zeae declined over time in all residues examined. Wheat and barley residues produced more ascospores of G. zeae than corn or other gramineous residues. Sunflower residue did not support ascospore production, indicating that it probably did not contribute to primary inoculum. Wheat and barley residues supported G. zeae colonization longer in no-till than in reduced-tillage production systems and, thus, may represent major contributors to Fusarium head blight (FHB) inoculum in Uruguay. The presence of G. zeae in the gramineous components of pastures, weed species, and sunflower should be considered when implementing control strategies for FHB.


Sign in / Sign up

Export Citation Format

Share Document