Be sure to use seed that does not have the pathogen in it. Planting late is more conducive to soybean aphid infestation, as infection in early growth stages can be the most detrimental.
Insecticides may be used to control aphid populations, but studies have shown that it has virtually no net positive effect on the spread of the virus. This is because immediately following the eradication of aphids in the field, new swarms will enter the area, possibly carrying in other viruses. Please contact your local plant pathologist to learn what is most effective in your area and how to use it best. Always read and follow all label instructions.
Some varieties of soybean have resistance to SMV.