Colletotrichum truncatum and Glomerella glycines
Anthracnose occurs sporadically throughout soybean fields in NY, though rarely reaches epidemic proportions. The disease is more prevalent during warm, humid conditions. Infection may occur at any growth stage, but symptoms usually develop during the reproductive stages.
Symptoms may include small lesions on leaves, petioles and stems. Lesions may expand into cankers which may girdle stems and petioles, resulting in a distinctive ‘shepherd’s crook’, and premature defoliation may occur. The pathogen survives on soybean residue, or in infected seeds. Planting infected seeds may result in damping-off of seedlings.
Seed treatments, tillage and crop rotation are good management practices for fields with a history of anthracnose.