Also known as Pink snow mold, Fusarium patch
Monographella nivalis (Schaffnit) E. Müller [teleomorph]
Microdochium nivale (Fr.) Samuels & I.C. Hallett [anamorph]
- Symptoms: The blotching caused by this organism becomes evident on leaves at about late-joint to early-boot growth stage. Young lesions occur as oval to elliptical, greyish green mottled areas, usually located where the leaf bends (picture at left).The lesions enlarge rapidly, developing into large, "eyespot" blotches with bleached or light grey centers; the leaves tend to split or shred, beginning at the centers of the lesions (picture on right) . The fungus also can cause seedling blight, foot rot, head scab (picture below at left) and, in winter cereals, pink snow mold.
- Development: Spores are produced on crop debris left on or near the soil surface. These spores are transmitted to leaves by the wind or by splashing rain. Disease development is favored by cool, moist weather.
- Hosts/Distribution: Generally, the disease affects durum wheat and triticale more than bread wheat or rye; oats and barley appear to be immune. Reports indicate that the disease is restricted to East Africa, the highland areas of Mexico, the Andean region of South America, and parts of southern China.
- Importance: Severe disease development can cause complete defoliation, resulting in poor grain development, shriveling, and low test weights (grain picture).