Agronomy Insights

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Crop Intelligence Insight
Disease Risk

Fungicide Decisions:

  • Fungicide Decisions are some of the most difficult you make on the farm each year.
  • Your Field Connect weather station and the Crop Intelligence app can provide supporting information to help make fungicide decisions.
  • Environmental Conditions play an important role in disease risk.
  • Yield Potential can bring clarity to the economics of the decision.
Disease Risk:
Susceptible Host:
  • Varietal resistance ratings
  • Crop stage
Pathogen:
  • Field history and rotation
  • Regional risk
  • Pathogen biology
Conducive Environment:
  • Current environmental conditions.
  • Future environmental conditions (weather forecast).

Environmental Conditions:
Field Connect Data

  • Rain: rain events in the two weeks prior to potential spray timing should be considered. Even small rain events <5 mm can contribute to disease risk.
  • Soil Moisture: moist soil at the surface increases disease risk.
  • Air Temperature: moderate temperatures 15-25?C are ideal for most pathogens.
  • Soil Temperature: soil temperature around 20?C.
  • Relative Humidity: greater that 50%.
  • Leaf Wetness: values above 5K indicate moisture in the crop canopy. When leaf wetness is sustained for >12 hours – disease risk increases.

Yield Potential:

Crop Intelligence Data


Water Driven Yield Potential can provide an indication of how much yield potential there is to preserve.

Leaf Wetness Sensor:

  • Quantifies the amount of water on its surface, which can be a good approximation of the amount of water on the leaves in the canopy.
  • A leaf is considered dry around 4200 and at 5000 there is moisture within the canopy.
  • Greater than 5000 over 12hrs indicates increased disease risk
Canola Risk Assessment:

FHB Risk Assessment:

Pulse Risk Assessment:

In pulses it is important to consider:

Boots on the Ground:


Nothing replaces boots-on-the-ground when assessing disease risk. 
  • Crop Intelligence and Field Connect can provide supporting information – but the context of what is going on in the field is required to make an informed decision.
  • Plant stand and canopy closure.
  • Visual appearance – yield potential.
  • Visual appearance – disease symptoms.
  • Moisture on the soil surface and in the crop canopy.