The frequent rains this spring are having an impact on corn seedlings, as many fields contain standing water for days at a time. The ability of corn seeds and seedlings to withstand periods under water is influenced by the activity of pathogenic fungi. The standing water aids dispersal of fungi, especially Pythium, which produces swimming spores. Damage due to Pythium typically is worse when soils are cooler, but it can still function in warmer soils. Also, other fungi are capable of attacking seedlings under current soil condition.
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