By Clint Thompson
Weather conditions have been conducive for disease buildup in Georgia peanuts, one disease in particular; white mold.
Bob Kemerait, University of Georgia Extension plant pathologist, discussed his concerns with white mold at last week’s Southern Peanut Growers Conference in Savannah, Georgia.
“What concerns me most as an Extension specialist in Georgia and working with diseases on peanuts is the kind of weather we’re having this summer, especially with what we’re having right now. In Georgia, we have been very dry, but we also now have very high humidity. We have high daytime temperatures, and we have high nighttime temperatures. We have sporadic rainfall. In my world, if you add all of that up, it spells white mold,” Kemerait said.
“We can’t do anything about tomato spotted wilt virus, and leaf spot has been quiet so far and we can’t forget about it, but the conditions right now for white mold is if the match has been struck. If I can get one word to all growers, now is the time to be aggressive. Now is the time to take charge, and don’t let white mold get a hold in your field.”
Disease Background
White mold is often the No. 1 cause of the loss of peanuts due to disease in a given season. Sclerotium rolfsii, the causal agent of white mold, is a fungus that remains in the soil between cropping systems and waits for the next susceptible crop to be planted.
Kemerait emphasizes the severity of white mold damage on peanuts and the importance of funneling the fungicide sprays into the crown of the plant.
“What concerns me most about white mold is how damaging it can be, if it’s not managed; the necessity to manage it before it gets started and just the general difficulty in getting the fungicide to where we need it to be,” Kemerait said. “On white mold we can’t just spray, we have to get it down into the canopy down in the crown of the plant where that white mold fungus is eating, living and surviving.
“If we don’t get a hold of it early, then it gets more difficult.”