Randy S. Sanderlin, Melanson, Rebecca | 7/15/2008 2:23:21 AM
None of the pecan cultivars is totally resistant to scab disease. Some cultivars have a greater degree of resistance to the scab pathogen than others, but even those cultivars are not completely resistant. Each pecan cultivar is infected by a different race of the scab pathogen. While there may not be a race that is able to easily infect a new cultivar when it is released, over time, as those cultivars are propagated, new races of the pathogen will evolve and the degree of resistance of those cultivars to the pathogen will decrease.
Question answered by plant pathology researchers at the Pecan Research-Extension Station.
The LSU AgCenter and the LSU College of Agriculture