Aphanomyces
(click image to enlarge) Symptoms:
• Brown, water-soaked lesions near soil surfact extending up to cotyledons
• Infected stems & roots will turn black and shrivel up to a slender thread
• Cotyledons only wilt at advance stages, "damping-off"
Epidemiology:
• Favored by warm temperatures (68-86° F)
• Inactive below 59° F
• Favored by wet soils & low soil pH
• Can be found in over-irrigated light textured soils
• Severe in heavy, poorly drained soils or wet areas
Control:
• Seed treatments with hymexazol
• Plant in cool, well drained soils
• Avoid excessive soil moisture