Released March 4, 2008
AMES, Iowa -- Iowa farmers may want to consider their own side-by-side trials if they plan to implement a preventive fungicide program to increase corn yield in 2008, says Roger Elmore, a corn agronomist with Iowa State University Extension.
“There is only a 1 in 4 chance that applying fungicide will be economically sound,” Elmore said. “The only way to really know if you’re getting that benefit is to put out some check strips in your own field and do some side-by-side testing with replication.”
It is not fair or accurate to compare year to year because too many other variables play into yields from one year to the next, Elmore said. Instead, split the field into equally sized portions and randomly apply different treatments to each. The harvest area of each treatment needs to be identical. For example, this could be accomplished by treating a 16-row section with fungicide, leaving the next 16-row section untreated and then harvesting the middle four rows for comparison. If the fungicide is applied by air, wider strips are necessary to accommodate the spray pattern and alleviate possible drift concerns.
The best way to compare is by replicating the process within a field or across multiple fields, he continued. For example to replicate across fields, if 10 farmers in the area are interested in using preventive fungicide to increase yield, they should all conduct the tests in about the same way. This will provide the most accurate results.
“Whatever you do, you have to do it in a fair and nonbiased way,” Elmore noted.
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http://www.extension.iastate.edu/news/2008/mar/120402.htm
Contacts: Roger Elmore, (515) 294-6655, relmore@iastate.edu
Laura Sternweis, (515) 294-0775, lsternwe@iastate.edu
