There have also been reductions in grade and quality. Biology Fusarium head blight overwinters in soil, grass and crop residue as well as in the seed. Seedlings may become infected at emergence. Spores are produced first on stem infections at the base of the plant. As warm, moist weather develops, spores are spread by rain or wind to infect flower parts, glumes or other portions of the head.
Infections are most frequent and severe at anthesis.
Symptoms of Damage Head blight is recognized by premature bleaching of one or all of the spikelets in the head. The infected spikelets are often sterile. The seed in the spikelet stalk, above the point of infection, may not develop. Diseased heads have small dark spots and exhibit fungal growth with an orange to pinkish tinge. Infected grain is shrivelled and lighter in weight.