Fusarium head blight in western Canada
Randy Clear and Susan Patrick, Mycology, Canadian Grain Commission
Revised
1884 - The disease was first described in England, where it was called wheat scab.
Fusarium head blight in the eastern Prairies
1900 - F. graminearum scab was identified in Minnesota.
1915 - Scab was common enough on wheat in Minnesota to cause concern. F. graminearum had already been a problem for several years on corn in Minnesota and North Dakota.
1923 - Different varieties of wheat in Minnesota displayed different responses to fusarium head blight-the disease had become more prevalent with the general adoption of Marquis wheat (MacInnes and Fogelman).
1923 - F. graminearum was reported on corn stubble in Manitoba (Bisby and Bailey).
1932 - Of 776 Fusarium isolates collected in Manitoba, none were F. graminearum (Gordon 1933).
1937-1942 - F. graminearum was isolated from 11 of 3094 Manitoba cereal samples (0.3 percent of the samples) (Gordon).
1939-1943 - F. graminearum was described as rarely isolated from cereal seeds produced in western Canada.
1944 - Fusarium head blight, called scab, already common in southern Minnesota and North Dakota, was found to have spread farther north and west (Tervet).
1946 - F. graminearum was not detected in Manitoba soil samples (Gordon).
1948 - In Winnipeg, F. graminearum was isolated from one out of six wheat heads with symptoms of fusarium head blight (Gordon et al).
1984 - F. graminearum heavily infected a sample of Coulter amber durum and Sinton red spring wheat from the Red River Valley of southern Manitoba (Clear and Abramson).
1985 - The first CGC survey for FDK found F. graminearum in 30 wheat samples , primarily from the Red River Valley (Abramson et al). Durum and Canadian Prairie Spring (CPS) wheats were more affected than Canadian Western Red Spring (CWRS).
1986 - F. graminearum was detected in 71Manitoba wheat samples containing FDK. The situation worsened in the Red River Valley (Clear and Patrick). Durum and Canadian Prairie Spring (CPS) wheats were more affected than Canadian Western Red Spring (CWRS).
1987 - Although F. graminearum was widespread in Manitoba, F. avenaceum was the most common species in samples with fusarium head blight. However, both types were found only in amber durum wheat. F. graminearum was not found in the 14 durum wheat samples with FDK from Saskatchewan (Clear and Patrick).
1991 - High levels of fusarium-damaged kernels were found in some samples of CWRS wheat. Most of the damaged wheat was of the variety Roblin, which was 21.9 percent of bread wheat acreage in Manitoba in 1991.
1993 - Record rainfall across the prairies was associated with record high infection levels of F. graminearum in Manitoba. Disease levels greatest in southeastern Manitoba. Nearly half the bread wheat acreage in Manitoba had been planted to Roblin, a very susceptible variety to FHB. High levels of infection in barley. Disease also reported in oats. F. graminearum was found in a few durum wheat samples from southeastern Saskatchewan.
1994 - Fusarium head blight was still located primarily in the Red River Valley, but was less severe than 1993. Trace levels of fusarium head blight were found in all Saskatchewan crop districts bordering Manitoba.
1995 - Spotty rains in Manitoba during flowering resulted in some intense localised infections. Reports of fields (at the same growth stage) only a few kilometres apart with widely different levels of infection and DON were common.
1996 - This was the third worst year for FHB in Manitoba. The area of south western Manitoba was one of the areas of highest infection. Testing carried out by the GRL showed Fusarium graminearum to be more common in samples from Saskatchewan than in previous years, especially from locations along the Manitoba-Saskatchewan border. With the exception of two samples (one at Oxbow, one at Carrot River), the levels of infection were very low, but more Saskatchewan samples were found to contain a detectable level of infection than had been found in previous surveys. Fusarium head blight caused by F. culmorum was also more common in 1996 Saskatchewan wheat than previous years. F. culmorum is a much less common but still potent DON producer.
1997 - Levels of FHB in Manitoba were very similar to those of 1996, with the south-west once again being one of the hardest hit areas and the north-west the least affected. In Saskatchewan, for the first time, F. graminearum replaced F. avenaceum as the dominant species recovered from FDK. This shift was mostly due to an increased incidence of F. graminearum in the eastern part of Saskatchewan, especially the south-east. Levels of FHB outside of Manitoba continue to be very low.
1998 - In Manitoba, FHB was once again a problem, with overall severity and incidence similar to that in 1997. As in 1997, south-west and south-central Manitoba were the hardest hit areas. Northern parts were much less affected. Due to plentiful rain in June, winter wheat in Manitoba had high levels of FHB for the first time. In previous years this crop had escaped the disease. In Saskatchewan, favourable disease weather combined with a build-up of F. graminearum inoculum over the last few years resulted in a dramatic rise in the incidence and severity of FHB in the south-east. For the first time, FHB was an important disease in this area. Since 1993 we have found an increasing incidence of F. graminearum in that area. This year marks the first time that F. graminearum was of economic importance in any area of the Canadian prairies outside of Manitoba.
1999 - Levels of FHB were lower than in 1998. Excessive spring precipitation in southwestern Manitoba and southeastern Saskatchewan resulted in many fields being left unseeded. A wide range of heading times occurred across the eastern prairies due to seeding delays in some areas. Pockets in eastern Saskatchewan and Manitoba with high disease levels, but overall FHB levels were down from 1998
2000 - Losses to FHB were the highest to date as a result of a combination of elevated disease levels and a greater affected area. Especially hard hit were the south central CDs of Manitoba. Highest disease levels in Saskatchewan were in the south east.
2001 - Once again ideal disease weather in Manitoba and south-eastern Saskatchewan resulted in high levels of FDK. Especially hard hit were areas around Winnipeg, Levels in south-east Saskatchewan were the highest yet for that area, However, very dry conditions outside the south-east corner resulted in less FDK in those areas than in recent years.
2002 - Incidence of FDK in Manitoba and eastern Saskatchewan was higher than last year, but severity was down. F. graminearum was once again the major cause of FDK in the wheat.
Fusarium head blight in the western Prairies
1984, 1987, 1989-1993 - Fusarium head blight caused by F. culmorum was found in irrigated soft white spring wheat (SWS) in southern Alberta. Beginning in 1989, we began to detect a few kernels of SWS wheat infected by F. graminearum.
1994 - F. graminearum was found at a high level in a Canada Prairie Spring wheat sample from west central Alberta.
1995 - FHB was found only in trace amounts in the irrigated areas of southern Alberta.
1996 - F. graminearum and F. culmorum were detected once again in the irrigated areas of southern Alberta, but at relatively low levels. As in other years, F. culmorum and F. avenaceum were also detected in Alberta samples from a few other areas. A few wheat seeds infected by F. graminearum were detected around Edmonton, Alberta, and in northwestern Saskatchewan. Many reports of over-wintered grain containing pink and red kernels were received from northern Saskatchewan and Alberta during the spring of 1997. The species responsible for this discolouration in all samples submitted for testing was F. avenaceum. DON was not detected in these samples (detection limit of 0.5ppm).
1997 - F. graminearum continued to be a rare species in Alberta and western Saskatchewan. However, it was detected in a few more locations near Edmonton, and for the first time in the Peace River area of Alberta. It was once again detected at very low levels in seed from the irrigated areas of southern Alberta.
1998 - In Alberta, levels of F. graminearum continue to be very low, although we did recover it from more locations and samples than in any previous year. In 1998 it was fairly common in the irrigated areas of southern Alberta, as was F. culmorum. This is likely due to the unusual occurrence for this area of abundant natural precipitation falling in June, giving ideal moisture conditions for FHB. In Alberta and western Saskatchewan FHB is still a very minor disease, although F. graminearum infected a greater percentage of FDK than in previous years.
1999 - Dry conditions in northern Alberta and unusually cool weather in central and southern Alberta did not appear to favour the development of FHB. Once again, very few samples with FDK were received from Alberta and western Saskatchewan, and only a small number of these were infected by F. graminearum.
2000 - Suitable conditions for the production of FDK occurred over much of the dryland farming area of Alberta, resulting in an increased number of samples being detected with FDK. However, levels of FDK in the samples was almost always very low, and the causal species was primarily Septoria nodorum and F. avenaceum. F. graminearum was found in only a very few fields in Alberta and western Saskatchewan. A drought in southern Alberta resulted in very few FDK being produced in that area.
2001 - A record drought affected much of the western prairies in 2001. In Alberta, 33 wheat samples with FDK caused by F. graminearum were found. Thirteen of these were from the Peace River area. Only a very few were from southern Alberta.
2002 - Drought affected much of the northern part of the western prairies in 2002. However, unusually wet weather in the southern areas caused a considerable increase in the number of samples with FDK and the number of FDK in the samples. This was especially true in southwest Saskatchewan and southern Alberta where most of the affected samples were amber durum wheat. Although the levels were usually low compared to the eastern prairies, they were much above what is normally encountered. In southern Alberta, 82 of the 191 samples with FDK had F. graminearum as one of the causal agents. F. graminearum and F. culmorum were the major causal agents of FDK in southern Alberta, but F. avenaceum and S. nodorum were much more important in southwestern Saskatchewan. Although unusually wet weather occurred in southern Alberta in both 1998 and 2002, F. graminearumFDK as well as the level of FDK was noticeably higher in 2002.
For more information
Randy Clear, Mycology
Canadian Grain Commission
Grain Research Laboratory
Telephone: (204) 983-7797
Email:
rclear@grainscanada.gc.ca
