Is there a way to estimate yield lost because of leaf diseases?
Researchers in Europe developed yield loss estimates for scald in barley. They found that yield loss was proportional to the area of the flag leaf and second last leaf infected by disease, according to the following equation . Yield loss (%) = (2/3 of the area of the flag leaf infected (%) + of the area of the second last leaf infected) /2 For example, the yield loss with 30% of flag leaf infected and 50% of second last leaf infected would be (30*2/3 +50*1/2)/2 = 22.5% Although this equation was developed specifically for scald in barley, it can probably also be used to roughly estimate the yield losses due to other leaf diseases in wheat or barley.
