Colletotrichum lindemuthianum 1. Attacks all above-ground plant parts. Small angular lesions on leaves and lower veins turn black. Tiny brown spots on pods that later enlarge, turn black with light brown to purplish borders.
Mature spots are circular to oval and sunken.
Use western grown certified seed to minimize disease. Do not work in garden when plants are wet. Use a three-year rotation. Remove residue after harvest. Leaves have irregular watery light green patches.