A comprehensive survey of fusarium head blight infection in Alberta shows that corn country is the epicentre of the disease.
The Municipal District of Taber and Counties of Lethbridge and Newell had the highest percentage of fusarium infection in the province in both cereal and corn samples.
However, researchers said corn growers are not concerned about fusarium and that might be a shortsighted view.
The 2010 survey of more than 900 fields showed a provincewide infection rate of six percent in cereal stubble, 13.6 percent in cereal grain and 42.2 percent for corn stalk samples.
Read Also
Lower U.S. spring wheat yields to cut production
The U.S. Department of Agriculture’s crop production and world agricultural supply and demand estimates reports were released July 11 with the main focus on the wheat, corn and soybean estimates.
“We knew that corn was a great host for fusarium. We didn’t expect 42 percent,” said research scientist Michael Harding, who assisted with the survey.
The MD of Taber has the highest percentage of infected cereal seed samples at 48.6 percent and the County of Lethbridge had the highest cereal stubble infection at 36.7 percent. About 86 percent of cornfields are infected in the region.
“This is the epicentre for fusarium in Alberta,” said Harding. “The disease is well established in southern Alberta.”
The study concentrated on the graminearum type of fusarium, which is the main pathogen affecting crops. It reduces crop yield and produces vomitoxins that reduce feed quality and affect milling, malting and ethanol production.
Fusarium is a declared pest under the provincial Agricultural Pests Act and there is a management plan now being updated to control its spread.
Corn is not responsible for fusarium. It is a host for the fungus, as are many other crops. Durum is particularly susceptible to infection.
And although fusarium loves corn and the hot moist conditions that come with irrigation, corn growers do not seem concerned about fusarium, said Harding and lead crop pathology researcher Ron Howard of Alberta Agriculture.
Fusarium causes stalk rot in corn, but growers haven’t experienced significant yield losses or “a pinch in the pocketbook” from that aspect of the fungus, said Howard.
“The biggest concern is amongst the cereal producers.”
However, fusarium’s production of micotoxins might have other implications for feed consumption, because most Alberta corn is grown for silage, as is a considerable amount of cereal grain.
“Millers, brewers and ethanol people are testing for fusarium in any and all grain and they may refuse to buy any grain with high levels of fusarium, or even moderate levels,” said Howard.
Harding said he presented the 2010 survey findings to corn growers and asked for questions. There were none.
“So I said, ‘well I have a question. How much of a concern is fusarium head blight for you as corn producers?’ And unanimously they said it’s not an issue for us. They don’t see any yield penalty. There aren’t many corn producers who see a significant reduction in yield due to fusarium.”
Harding said the reaction is in part because silaging a crop is one of the best management practices to control fusarium. That’s good, but it isn’t the whole answer.
“Putting corn into silage isn’t going to prevent the disease. It’s just going to limit its spread. Based on what we know about the epidemiology of the disease, the more corn that goes in rotation with wheat and barley, the higher the risk,” Harding said.
The survey also showed fusarium infection in four cereal fields in central and northern Alberta and in the Ponoka, Wainwright and Two Hills areas. Researchers plan to revisit those areas next year and will also resurvey municipalities on the perimeter of the most heavily infected regions in the south, said Howard.
Provincial fusarium surveys were done in 2000 and 2006 and the 2010 version showed that the disease has intensified.
Control measures include planting clean seed, crop rotation, use of fungicides and managing the timing of irrigation.
Howard and Harding said there are opportunities to limit fusarium’s spread into the northern part of the province, where the disease is not well established.
MANY ALIASES
Fusarium by any other name would be as nasty. The fungal disease is also known as:
• Scab
• Tombstone
• Head blight
• Pink mould
