By Ryan McGeeney
A bedrock principle of efficient farming is scouting your fields before applying pesticides — whether herbicides, insecticides or fungicides. This not only helps farmers save money but reduces the likelihood of pesticide resistance developing as well.
Terry Spurlock, professor and extension plant pathologist for the University of Arkansas Division of Agriculture, recently published an update on an ongoing study of the use of fungicide applications in soybeans. The study, funded by the Arkansas Soybean Promotion Board, began in 2020.
Spurlock said that while fungicides are an important tool to manage foliar diseases in any farmer’s toolbox, growers should use them only when scouting reveals the presence of a fungal pathogen that exceeds an economic threshold.
“When you average across all treatments, all trials, all years, without consideration of disease or product, it’s about 3.3 bushels of an advantage to applying a fungicide,” he said. “But when soybeans are, say, $10 a bushel, that will get you an extra $33 an acre. Well, if a fungicide application is also $30, then you break even.
Data from the study was collected across 53 on-farm trials over five years, according to the research update.
Preventing fungicide resistance
“There are times when an automatic application works out well, when yield-limiting disease develops shortly after application, and there are times when you actually lose money, when little or no disease develops,” Spurlock said.
Source : uada.edu