Fusarium species in underground tissue of pulse, oilseed, and cereal crops grown in southeast Saskatchewan

Non-Peer ReviewedA total of 643 cereal, oilseed and pulse crops were sampled in southeast Saskatchewan in 2000 and 2001 for Fusarium populations in underground living tissue. Many of the Fusarium spp. isolated from discolored roots/subcrown internodes had also been isolated from cereal heads affected by Fusarium head blight (FHB) in Saskatchewan. The most abundant Fusarium spp. were F. avenaceum and F. equiseti. F. avenaceum was present at the highest level in pulse, particularly lentil. Other species present at lower levels in both cereal and non-cereal tissue were F. acuminatum, F. culmorum, F. graminearum and F. sporotrichioides. When fungal populations in discoloured subcrown internodes of wheat and barley were analyzed according to crop history, it was found that a preceding non-cereal crop did not change the percent isolation of most species, including the cereal pathogens F. culmorum and F. graminearum. Furthermore, in most cases the percent isolation of total Fusarium spp., particularly that of F. avenaceum, was higher when wheat or barley were preceded by a non-cereal crop than when preceded by another cereal crop or summerfallow. This is the first report of isolation of F. graminearum, the main causal agent of FHB in North America, from roots of field-grown pulse and oilseed crops in western Canada

Management of red smudge in durum wheat

Non-Peer Reviewe

Could chemical seed treatments limit the spread of Fusarium graminearum through infected seed?

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Evaluation of bacterial strains for control of Fusarium graminearum and other cereal pathogens

Non-Peer ReviewedFungal pathogens causing disease in cereal crops result in considerable economic losses for producers across western Canada. Cultural practices including crop rotation and fungicide use are recommended for their control. At present, the use of chemical fungicide has fallen out of favour due to the possibility of chemical residues in food, impact on non-target organisms and worker exposure. For these reasons, biological control may be a viable alternative if effective microorganisms can be identified. The objective of this study was to isolate, screen and characterize microorganisms from soil and crop residues that could antagonize cereal pathogenic fungi and lead to the development of biological control agents for important cereal pathogens

The impact of agronomic practices on the development of Fusarium head blight in eastern Saskatchewan

Non-Peer Reviewe

Effect of wheat seed colour on the incidence and severity of red smudge and black point caused by Pyrenophora tritici-repentis

Non-Peer ReviewedPyrenophora tritici-repentis (Died.) Drechs. (anamorph Drechslera tritici-repentis (Died.) Shoemaker) causes red smudge, black point and dark smudge (Fernandez et al., 1998; 2001; Francl and Jordahl, 1993). This discoloration could result in downgrading due to low tolerance levels in the top grades (Canadian Grain Commission, 1994). Incorporation of disease resistance into all wheat classes would therefore be of economic benefit to producers. Fernandez et al. (2001) determined that cultivars in all four wheat quality classes tested were susceptible to P. tritici-repentis but that they differed in the predominant type and/or intensity of the discoloration and in incidence and severity of the infection. Some of the differences in the incidence and severity of the discoloration among cultivars appeared to be related to seed colour. Because there were differences also within classes not related to seed colour, the impact of seed colour per se on the development of kernel discoloration caused by P. tritici-repentis could not be accurately assessed. The objective of this study was to assess the incidence and severity of kernel discoloration caused by P. tritici-repentis in near-isogenic lines for seed coat colour so that genotypic effects could be separated from seed colour

How rotation and tillage system affect Fusarium populations in wheat and barley in eastern Saskatchewan

Non-Peer Reviewe

Effects of crop management on leaf spots of wheat in eastern Saskatchewan

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Preliminary investigations on the effect of commercial glyphosate formulations on pathogenic Fusarium spp.

Non-Peer ReviewedDiseases of cereal crops caused by pathogenic fungi can lead to estimated economic losses of over $100 million to producers annually in western Canada. One fungal disease that is becoming more prevalent in Saskatchewan is Fusarium head blight (FHB), caused primarily by Fusarium graminearum and to a lesser extent F. avenaceum. These pathogens can reduce grain yield and quality. There is a very low tolerance for Fusarium damaged kernels in grain samples due to the presence of mycotoxins that are very detrimental to human and animal health. This disease also causes reductions in seed germination and seedling vigour. Cultural practices including crop rotation and fungicide use have done little to reduce the impact of FHB. However, recent studies have shown significant reductions of FHB severity in fields under zero-till production systems compared to minimum-till systems. One factor which may contribute to the lower FHB in zero-till than min-till may be the greater use of glyphosate-based herbicides in the zero-till systems. A study was conducted to evaluate the effect of different commercial glyphosate-herbicide formulations on the in vitro growth of cereal pathogenic Fusarium spp

Rotation and fertility effects on root rot of spring wheat in southwest Saskatchewan

Non-Peer ReviewedSpring wheat grown in a replicated trial for one or two years after summerfallow, lentil, flax, or continuously (with and without fertilizer N) was examined for subcrown internode discoloration from 2000 to 2002 in southwest Saskatchewan. Discolored tissue was plated on nutrient agar for fungal identification. Root rot was in general present at highest levels in wheat grown after lentil, and at lowest levels in wheat grown continuously with low N fertility. The most common species were Cochliobolus sativus and Fusarium spp. Among the latter, F. avenaceum, F. equiseti and F. pseudograminearum were the most commonly isolated. F. avenaceum is the most important fusarium head blight (FHB) pathogen in western Saskatchewan. The percent isolation of Fusarium species was lowest in continuously-grown wheat with low N. Wheat after lentil had one of the highest levels of F. avenaceum. Among the crop rotations examined, it appears that the most favourable to the development of root rot in spring wheat was a wheat-lentil rotation. This rotation may also contribute to the build-up of F. avenaceum inoculum for the development of FHB, which is an important emerging disease of wheat and barley in western Saskatchewan