Department of
Plant and Soil Sciences



Research Partners

Monitor SBR Spread



How to use Yield Loss Prediction Tool

 

Inputs:

 

Fungicide Cost: Enter the cost per acre for fungicide recommended for control of SBR.

 

Application Cost: Enter the cost per acre for application.

 

Hauling and/or Harvest Cost: Enter the cost per bushel for hauling crops as well as the harvesting cost if it is on a per bushel basis. If cost is charged on a flat rate basis (i.e., $/acre), then leave this line blank.

 

Other cost: If you have any other costs, directly associated with control of SBR enter the values per acre. If you are not expecting any other expenses you can leave this field empty or enter 0.

 

Predicted Potential Yield: Enter expected yield in the absence of SBR (e.g., 5-year average) in bushels per acre for each individual field.

 

Price of Crop: Enter expected price for crop at harvest (or a storage-cost adjusted price if crop is stored).

 

Growth stage: Planting date, location, variety and weather can influence plant development, so each field is likely to be at a different growth stage. Therefore, visit each field to determine the growth stage of the crop. At least one sample of 10 arbitrarily selected plants for every 10 acres should be used to make growth stage determinations. The stage of the field is based on 50% of the plants at or beyond a particular growth stage. If you need help to determine crop growth stage click here Images

 

Outputs:

 

Epidemic scenarios:

 

Severe: Worst case scenario with ideal moisture and temperature conditions for rapid spread and increase of SBR resulting in severe damage to the crop.

 

Moderate: Moisture and temperature conditions are not ideal for SBR. There may be periods when the temperatures are too high or periods of leaf wetness are too short for rapid development of the SBR epidemic. The epidemic results in moderate damage to the crop.

 

Light: Weather conditions are not favorable for SBR spread and development. Little to no yield loss results.

 

Disclaimer

The model that the SBR Yield Loss Prediction Tool uses to estimate yield losses was developed with data from trials in Brazil with severe SBR epidemics. Validation trials were conducted in the U.S. to test how well the model estimated yield losses under a number of row widths, genotypes and growing conditions. However, these only represent a small sampling of the genotypes, row widths, growing conditions and management operations likely in the southern U.S. The use of this model for prediction of relative yield loss across a wide range of soybean production systems in the southern U.S. must be taken with the understanding of these limitations. In addition, the scenarios for ‘moderate’ and ‘light’ epidemics are not based on independently validated data, but represent hypothetical scenarios, based on what is ‘likely’ to occur to the lag phase and the rate of disease progress under the three scenarios. Again, yield loss predictions based on the ‘moderate’ and ‘light’ epidemics must be taken with the understanding of these limitations.