New alfalfa seedings are reported to be in good shape throughout the state, but the recent wet weather may result in some seedling disease problems. The most important fungi attacking alfalfa seedlings areAphanomyces euteiches, Phytophthora medicaginis, and several species of Pythium. Other seedling pathogens include Fusarium and Rhizoctonia. According to a survey we did in 1994, Aphanomyces is more common than Phytophthora in Iowa soils, and these two fungi should be considered equal threats to seedlings. Seedling diseases should be suspected when emergence is poor or when there are obviously stunted, discolored, or dead seedlings.
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