Scouting is critical for mitigating impact on tar spot, as well as timely fungicide application.
Tag Archives tar spot
Tar Spot firmly planted in Ontario corn
Agriculture experts working to find hybrid and fungicide solutions to minimize impact
ForeSite targets early tar spot prevention
ForeSite is an adaptive, integrated modelling system for managing corn and tar spot that’s specific to Ontario
ForeSite is an Ontario-specific adaptive and integrated modelling system for managing corn and tar spot. It provides disease and aggregated insights, in-field weather, growth stage modelling and engagement reports, allowing agronomists and producers to hone field management, reducing costs and labour.
Relative humidity and leaf wetness impact tar spot growth
The southern Ontario situation in 2023 provided more insight on management strategies
A look at tar spot in Canada and the U.S. shows the vital role of humidity in fostering the disease. In 2023, the big difference between the U.S. and Ontario was dryness; Michigan and other parts of the Midwest were dry compared to much of southern Ontario. The provincial corn crop was also planted later, […] Read more
Biological control could help reduce tar spot challenges
Recent work studies the impact of Alternaria on impeding disease
Researchers and plant breeders have been working to develop ways to overcome tar spot in corn, but there three primary factors confound the search. For starters, the disease pathogen (Phyllachora maydis) only grows on living tissue. Recreating the ideal conditions under which the disease flourishes (temperatures between 16 C and 23 C and relative humidity […] Read more
Tar spot pressure low in Ontario so far
Tarspotter app can improve regional scouting
In early July, Albert Tenuta confirmed low incidences of tar spot in Elgin, Chatham-Kent and Essex counties. Tenuta, a field crop extension plant pathologist with the Ontario agriculture department, noted the initial positive through his West Elgin North American Tar Spot Trials, which run in conjunction with those of United States colleagues. Why it matters: […] Read more
Time to watch for tar spot, soybean cyst nematode
OMAFRA Field Crop Report for the week of June 26
Tar spot has now been established in the midwestern US for almost a decade and is an annual concern in many Midwestern states like Illinois, Indiana, Iowa, Michigan, and Wisconsin. While tar spot was not as yield-limiting in these areas in 2022, it continued to expand its range across the corn belt, as far west as Kansas […] Read more
Search is on for a response to tar spot
University of Illinois researchers study exotic sources of resistance
Crop diseases often carry a disturbing mix of known and unknown factors. Take tar spot in corn, as an example. It’s known to have arrived in Ontario in 2018 and has continued to spread across the province, from a few fields in five counties in 2020 to a wider distribution in 19 counties by the […] Read more
Top strategies for managing tar spot
It’s all about tolerant hybrids, fungicides, and timing
Tar spot is now well-established in the province and experts from across North America encourage corn growers to think of it as a regional, not field specific disease. That would closely align with how white mould and fusarium head blight are considered. Proactive management is needed. The second day of the 2023 Ontario Agricultural Conference […] Read more
Illinois researchers seek weapons against tar spot in corn
Science Notes: The race is on to find genes that control tar spot resistance
Tar spot is a fungal disease of corn capable of causing significant yield loss. When it appeared out of nowhere in 2015, corn growers in the U.S. Midwest scrambled to manage the outbreak with few effective tools. Tar spot arrived in Ontario in 2021. The industry has since made progress toward management with fungicides, but […] Read more
Learning to live with tar spot
Know what decisions to make, and when to make them, are key to controlling the disease
Tar spot, the latest corn disease to cross the border, is in Ontario to stay. Knowing when the risk of tar spot development is high, how to identify the pathogen, and when to take remedial action is now the name of the game. Why it matters: A new fungal infection in corn could create the […] Read more
Cyber-Savvy Farmer
