Hyperspectral measurements of yellow rust and fusarium head blight in cereal crops: Part 1: Laboratory study

Roots of canola, flax, lentil and pea crops, commonly grown in rotation with wheat and barley on the Canadian Prairies, were sampled for extent of discolouration and associated fungal populations in eastern Saskatchewan, in 2000 and 2001. Fusarium was the genus most commonly isolated from pulse crops, particularly lentil, and one of the most common genera isolated from oilseed crops. The discolouration severity of pulse and flax roots was associated with Fusarium spp., and that of canola with Alternaria spp. Cochliobolus sativus and other commonly isolated species appeared to be present in roots as weak pathogens or saprophytes. Most of the Fusarium spp. have also been isolated from cereal crops affected by crown/root rot or fusarium head blight (FHB) in the province, although at different relative levels. These included F. avenaceum, the most commonly isolated species, and F. culmorum and F. graminearum, which were among the least prevalent species. This is the first report of isolation of F. graminearum from roots of field-grown pulse and oilseed crops in western Canada. For most crops, the number of tillage operations in the previous 3 yr was positively associated with the occurrence of C. sativus and negatively associated with that of F. avenaceum. Our results suggest that the noncereal crops examined would help to maintain or increase Fusarium inoculum in plant tissue, which might contribute to the development of crown/root rot and FHB in subsequently grown cereal crops, especially under conditions more conducive to disease development. This would especially be the case for pulse crops, which had the highest levels of root discolouration, and F. avenaceum. However, noncereal crops would not be significant reservoirs of inoculum of F. culmorum or F. graminearum. Key words: Fusarium avenaceum, Fusarium graminearum, Fusarium head blight, oilseed, pulse, cereal, tillage, crop rotation

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Evolution of Fusarium Head Blight Management in Wheat: Scientific Perspectives on Biological Control Agents and Crop Genotypes Protocooperation

Applied Sciences ◽

10.3390/app11198960 ◽

2021 ◽

Vol 11 (19) ◽

pp. 8960

Author(s):

Antonia J. Powell ◽

Vladimir Vujanovic

Keyword(s):

Fusarium Head Blight ◽

Management Strategies ◽

Cereal Crops ◽

Past Century ◽

Head Blight ◽

Promising Tool ◽

Cultivar Development ◽

Technological Advances ◽

The Us ◽

Moderately Resistant

Over the past century, the economically devastating Fusarium Head Blight (FHB) disease has persistently ravished small grain cereal crops worldwide. Annually, losses globally are in the billions of United States dollars (USD), with common bread wheat and durum wheat accounting for a major portion of these losses. Since the unforgettable FHB epidemics of the 1990s and early 2000s in North America, different management strategies have been employed to treat this disease. However, even with some of the best practices including chemical fungicides and innovative breeding technological advances that have given rise to a spectrum of moderately resistant cultivars, FHB still remains an obstinate problem in cereal farms globally. This is in part due to several constraints such as the Fusarium complex of species and the struggle to develop and employ methods that can effectively combat more than one pathogenic line or species simultaneously. This review highlights the last 100 years of major FHB epidemics in the US and Canada, as well as the evolution of different management strategies, and recent progress in resistance and cultivar development. It also takes a look at protocooperation between specific biocontrol agents and cereal genotypes as a promising tool for combatting FHB.

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Detrimental Effects of Multiple Mutations in Position 240 of Fusarium graminearum β2-Tubulin

Phytopathology ◽

10.1094/phyto-11-19-0409-r ◽

2020 ◽

Vol 110 (9) ◽

pp. 1522-1529

Author(s):

Yuanye Zhu ◽

Yuanshuai Zhang ◽

Zongzhe He ◽

Yabing Duan ◽

Yanjun Li ◽

...

Keyword(s):

Amino Acids ◽

Molecular Docking ◽

Fusarium Head Blight ◽

Binding Affinity ◽

Fusarium Graminearum ◽

Growth Rates ◽

Effective Concentration ◽

Cereal Crops ◽

Head Blight ◽

Tubulin Gene

Fusarium graminearum causes Fusarium head blight (FHB), a destructive disease of cereal crops worldwide. Carbendazim (methylbenzimidazol-2-ylcarbamate [MBC]) is widely used for controlling FHB. A previous study showed that the F240L mutation in the β2-tubulin of F. graminearum (Fgβ2-tubulin) confers hypersensitivity to MBC. Whether the substitution of phenylalanine by other amino acids in position 240 of the Fgβ2-tubulin gene also confers hypersensitivity to MBC is unknown. Moreover, the biological fitness of these mutants is poorly understood. In this study, we substituted position 240 of Fgβ2-tubulin with other amino acids. We found that the F240A, F240E, F240I, and F240Y mutations in Fgβ2-tubulin could also confer F. graminearum hypersensitivity to MBC, although the effective concentration resulting in 50% inhibition (EC50) differed among the mutations. The F240G mutation, in contrast, decreased the sensitivity to MBC. In addition, a molecular docking assay indicated that the binding affinity between Fgβ2-tubulin and MBC were increased by the F240A, F240E, F240I, and F240Y mutations but decreased by the F240G mutation. All mutants had normal conidial morphology, but the growth rates and pathogenicity of the F240A, F240E, F240G, F240I, and F240Y mutants were significantly decreased. Moreover, the F240A and F240G mutants produced twisted hyphae. In addition, microtubules were sparse and rarely observed in β2F240A-EGFP, β2F240E-EGFP, and β2F240G-EGFP. These results indicate that position 240 (phenylalanine) is not only vital to the function of Fgβ2-tubulin but also plays an important role in regulating the sensitivity of F. graminearum to MBC. Any mutation in this site would be detrimental to survival.

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Comparing Genetic Variation within Red Winter Wheat Populations with and without Image-Based Optical Sorter Selection

Al-Qadisiyah Journal For Agriculture Sciences (QJAS) (P-ISSN 2077-5822 E-ISSN 2617-1479) ◽

10.33794/qjas.vol9.iss2.82 ◽

2019 ◽

Vol 9 (2) ◽

pp. 266-277

Author(s):

Hussein M. Khaeim ◽

Anthony Clark ◽

Tom Pearson ◽

Dr. David Van Sanford

Keyword(s):

Genetic Variation ◽

Fusarium Head Blight ◽

Heading Date ◽

Fusarium Head Blight Resistance ◽

Gibberella Zeae ◽

Mass Selection ◽

Head Blight ◽

Red Winter Wheat ◽

Two Populations ◽

Head Scab

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.

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