Integrated Crop Management is published by the Department of Entomology , Iowa State University , Ames, Iowa. When growers start to combine, pathologists start to receive questions about discolored soybean seeds. For the last two years, we have received numerous reports of discolored seeds from producers, especially in southwestern and western Iowa. Areas where this problem was prevalent last year appear to have the problem again this year.
Growers are concerned about the effect of discoloration on seed quality.
A few common diseases that are causing seed discoloration this season are discussed in the following paragraphs. SMV is spread by aphids and BPMV may be spread by bean leaf beetles. The populations of these insects are large this year because of the mild winter. Seed discoloration from soybean mosaic virus. Seed infected with SMV may have a black discoloration from the hilum.