Producers may be anxious to get in new seedings of alfalfa, but the wet soils may result in seedling disease problems this spring. The most important fungi attacking alfalfa seedlings are Aphanomyces euteiches, Phytophthora medicaginis, and several species of Pythium. Seedling diseases should be suspected when emergence is poor or there are stunted, discolored, or dead seedlings. Like seedling diseases of other crops, alfalfa seedling diseases are more severe in wet conditions. Although cold soils also promote seedling diseases in general, alfalfa seedlings are more cold-tolerant than other crop seedlings, so soil temperature is not a major concern for alfalfa seedling diseases.
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