The U.S. Environmental Protection Agency has approved the use of Fortix Fungicide for suppression of Sudden Death Syndrome in soybeans.
Fortix is jointly marketed and sold by Arysta LifeScience and Cheminova, Inc.
Fortix is currently registered for use on corn, soybeans and wheat to control the major foliar diseases. The fungicide combines fluoxastrobin strobilurin from Arysta LifeScience and flutriafol triazole from Cheminova.
"SDS is prevalent throughout soybean-producing states," says Dr. Dunk Porterfield, Arysta LifeScience fungicide development manager. "It infects soybean seedlings shortly after planting, but symptoms are usually not apparent until mid-summer flowering."
Research indicates yield losses range from 20-30%, and in extreme cases can be as high as 70%.
"SDS is caused by a soil-borne fungus, Fusarium virguliforme, that infects the root and moves up the plant killing the leaves," explains Dr. Jim Barrentine, Cheminova technical director. "Optimum conditions for the disease are soil temperatures below 60 degrees at planting, moderate temperatures during the growing season, wet weather during the growing season and soil compaction. Unfortunately, highly resistant seed varieties do not exist."
Field trials conducted in 2014 show that Fortix Fungicide reduces the growth rate of Fusarium virguliforme, allowing the plant more time to photosynthesize and produce yield prior to premature defoliation caused by SDS. Fortix does not eliminate or prevent the spread of the disease.
"We saw an average yield increase of 8.9 bu/A when Fortix was applied before or at R1 with SDS present," Porterfield explains.
Porterfield says for best results growers should apply early – at first flower (R1). If applied after R1, growers should not expect to see significant impact on SDS, but it will control other foliar diseases. Lastly, growers should use at least the 5 fl oz/A rate.
Barrentine points out by applying Fortix, growers should see an added benefit of broad-spectrum foliar disease control including frogeye leaf spot.
For more information on Fortix, visit fortixfungicide.com.