Plant Health Initiative

Soybean Viruses - Agronomic Impact

Seed mottling reduces seed quality. Photo credit: X.B. Yang, Iowa State University

Infection by viruses reduces pod formation and seed size, weight, and number.

Bean pod mottle virus and soybean mosaic virus are associated with green stem syndrome, a delayed maturity of the stems and petioles, which makes harvesting more difficult. The effects of double infection by BPMV and SMV are much greater than of either virus alone.

Infection by viruses and damage to the seed pod can cause discoloration of soybean seed, also called seed mottling. Seed mottling is a brown or black bleeding from the the hilum, the scar where the seed was attached to the ovule. Mottled seed can be a sign of poor seed quality and results in financial penalties to producers.