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Control Recommendations Management Practices
Pesticides
Scab is early identified in the field when healthy heads are green.
Scab-infested spikelets appear prematurely bleached. Often spikelets in one-third to
one-half of the head are affected. In several cases the entire head may be colonized. The
bleached spikelets are either sterile or contain shriveled and discolored seed. Close
examination of affected spikelets may show superficial pink mycelia at the base of the
colonized spikelet. The fungi that cause scab overwinter on infested crop residues such as
cornstalks, wheat stubble, and stubble from other grasses. During flowering of the wheat,
spores are produced on these scab-infested residues. During moist, warm weather the
wind-borne scab spores infect and colonize the spent anther cases (pollen producing sacks)
of the flowering wheat and go on to invade the spikelet and developing seed.
The grain harvested from wheat fields heavily infested with scab is of poor quality, low
test weight, and often contains mycotoxin (toxins produced by fungi) that make the grain
less palatable to livestock and humans. Some of these mycotoxins induce vomiting and
muscle spasms in man and non-ruminant animals. Other mycotoxins can cause sexual
reproductive dysfunction. Some of these toxins can be intoxicating when bread is made from
"scabby" wheat.
| Disease Management Practices | Foliar Diseases | Seed and Seedling Diseases | Root and Crown Diseases | Head Diseases | Virus Diseases |
