This season at Innovation Farms we are examining the similarities and differences between two Fusarium head blight (FHB) risk models; a publicly available tool created by University of Manitoba researchers, and Metos Canada’s disease model subscription accessed through an on-farm weather station.

The University of Manitoba tool is a free resource that provides a broad overview of risk across the region, while the Metos Canada tool is a paid subscription that provides site-specific data unique to the farm that its weather station is located on.

What is Fusarium head blight?

FHB affects cereal crops such as wheat, barley, durum, and rye. It can cause significant yield loss and quality downgrades. Warm and humid weather conditions lead to a higher risk of infection which occurs from flowering to early grain development. Disease forecast models such as the ones developed by University of Manitoba and Metos help farmers determine if fungicides need to be applied. This technology offers vital insights, because by the time you can see FHB, significant damage has already been done.

Insights from University of Manitoba’s made-in-Manitoba risk mapping tool

Dr Paul Bullock, a senior scholar in the University of Manitoba’s soil science department has been working on a FHB risk mapping tool for the last five years. It is accessible through a tablet, phone, or computer. There are 121 of these stations across Manitoba including the Stonewall and Woodlands stations which are the nearest ones to Innovation Farms.

FHB Risk as of June 30, 2023
June 30 map indicates moderate to high FHB risk for the Stonewall – Woodland area

The disease risk model uses real-time weather data to assess the risk of FHB infection. It gathers data from over 500 weather stations across the prairies. All three Prairie provinces use these stations to provide farmers with weekly FHB risk maps.

This provides an important overview of potential risks, however the further away the station is, the less accurate it will be. According to Timi Ojo, an agricultural systems modeler with Manitoba Agriculture, each grid cell on the tool represents a 10 km radius.

Forecasts using an on-farm weather station are the most accurate, but it is not always economically possible for farmers to install unique weather stations across their farms. This model provides an overview that can help inform decisions in a way that would otherwise not be accessible to them.

Manitoba Agriculture posts these FHB risk maps daily throughout the season. The featured map was posted June 30. The areas in red show extreme risk, while orange shows high risk, light green shows moderate risk and dark green shows low risk.

According to this map, Innovation Farms is currently on the edge of the light green and orange regions indicating moderate to high risk.

Insights from Metos Canada’s risk model

The Innovation Farms team is also gathering information from the subscription-based Metos Canada’s Fusarium disease risk model which is generated using data from a local field weather station. These IoT monitoring devices and sensors help us determine exactly what local field-specific conditions are, which reduces trips to the field and helps us make timely decisions. This model is based on peer-reviewed research and looks for certain periods of temperature, relative humidity, and leaf wetness to assess FHB risk.

Metos FHB Risk Mapping Tool
Metos FHB Risk Mapping Tool shows data collected 1 ½ km apart

Previous studies have shown that weather devices that are only 1 ½ kilometres apart and in different crops have completely different environmental conditions for disease development, and the sensitivity of the model confirms these results (see image above which shows side by side results for two stations located at AIM’s field of excellence and at their main office).

As with most disease models several key environmental variables including temperature, infection curves, and crop flowering stages are examined in relationship to one another.

FHB strains prefer temperatures between 20-30 degrees Celsius for long periods of time. Infection pressure level in % depends on the intensity of the environmental factors over the time measured.

Risky periods occur whenever the infection curve reaches 100% which is what the current model (pictured below) is showing for the field at Innovation Farms.

Synchrony of disease risk to crop stage is extremely important. The grower needs to make sure the crop is nearing the early flower to early grain development stage which is the FHB infection window.

According to this Metos chart, there is currently a high risk of FHB at Innovation Farms
According to this Metos chart, there is currently a high risk of FHB at Innovation Farms

Next steps

As we enter July, our wheat is now approaching the FHB fungicide protection window so we are monitoring it very closely.

At this time, the risk percentage calculating the severity of risk in the two disease models does not completely agree. This can be attributed to multiple factors.

Delineation of each models’ specific thresholds may make the results seem quite different, for example these two models uses different temperature thresholds. The University of Manitoba model looks at the last 14 days’ temperatures between 25 to 28 whereas the Metos model looks at temperatures between 20 to 30 degrees Celsius. The University of Manitoba models use publicly available data from a weather network to interpolate the risk and is not meant to be a prescriptive but is a tool for farmers to assess general risk.

Later on this season at Innovation Farms we will validate the efficacy of both FHB models by collecting and grading grain samples in areas that are treated with a fungicide and samples will also be taken from specific areas where no fungicide was applied.

Follow #InnovationFarmsMB on Twitter and LinkedIn for updates throughout the season.

Written by Danielle Bérard, EMILI’s Innovation Farms Manager