DISEASES OF SOYBEAN – VIRUS DISEASES/GREEN STEM SYNDROME

Virus diseases including “green stem syndrome” are diseases of soybean that have become of particular interest to soybean researchers during the past 10 to 15 years. An increase in viral diseases of soybean has probably occurred during this period due to an increase in the insects that can carry viral pathogens, in particular the soybean aphid and bean leaf beetle. Viruses of particular interest include soybean mosaic virus(SMV), alfalfa mosaic virus (AMV), tobacco streak virus (TSV) and bean pod mottle virus (BPMV). Watch for virus problems in fields or areas in a field) with thin stands or where plants are under stress (e.g., water or nutrient stress). Stressed plants may be more prone to viral diseases due to their attractiveness to insects that carry these viruses.

Symptoms of viral diseases can be quite varied depending upon the virus involved. However, one symptom typical of many types of viral infections is mosaic, a botchy, irregular light and dark coloration of leaf tissue.