SCREENING TECHNIQUES AND SOURCES OF RESISTANCE TO ROOT ROTS AND WILTSIN COOL-SEASON FOOD LEGUMES

Soilborne, fungal pathogens of cool season food legumes, including see d and seedling blights, rot rots, and wilts are described. Seed and se edling diseases are caused primarily by Pythium and Rhizoctonia spp. T he most important fungi causing root rots include Aphanomyces euteiche s, Fusarium solani, Pythium spp., Sclerotium rolfsii, and Macrophomina phaseolina. Wilt is caused primarily by various host-specific forms o f Fusarium oxysporum. This paper discusses these diseases and screenin g procedures that emphasize standardization of inoculum levels, mainte nance of virulent pathogen cultures, inoculum growth media, environmen tal conditions, and host plant age. Sources of resistance to these dis eases are discussed.