The model simulation that drives the early warning system and
disease alerts start at the beginning of the wheat season. For each grid call found on the
map, the model simulates the number of spores that are present in the air.
These, in turn, express the amount of inoculum that builds up during the wheat vegetative
growth period. The model assumes that inoculum is present in the environment contained
within the grid cells and that it originates from
host plant tissues. These include wheat, but could also include secondary hosts such as
weeds. Based on the estimated number of spores in the air, each grid cell is empirically
categorized into one of three bins – (1) no risk,
(b) moderate risk, and (3) high risk – signified by different colors to indicate the risk of
an outbreak. The squares in green represent no risk while yellow and red squares indicate,
respectively, moderate and high risk. A
risk map is available for each of the five days forecasted.