Diseases

Sclerotinia sclerotiorum (Lib.) de Bary - Sclerotinia Rot of Maize.

Systematic position.

Class Ascomycota, subclass Leotiomycetidae, order Helotiales, family Sclerotiniaceae, genus Sclerotinia.

Synonym.

Sclerotinia libertiana Fuckel.

Biological group.

Hemibiotroph.

Morphology and biology.

Spots covered by white film of pathogen mycelium occur on lower part of maize stem. Plant tissue rots gradually, and sclerotia of the fungus form in places of damage. They are dark-brown, irregular-shaped, reaching 5 mm in diameter. Sclerotia keep in soil and plant debris. Under humid conditions the sclerotia produce apothecia forming asci with ascospores. Ascospores are the source of plant infection.

Distribution.

The disease is spread in foothill and other regions of the Caucasus, and in Kuban River region, which are characterized by humid climate.

Ecology.

Rainy weather and high air humidity are favorable for the disease development.

Economic significance.

Protective measures must be used, e.g., removal of infected plants and plant debris, crop rotation with sowing the agricultural plants being unaffected by this disease (cereals, forage crops, and others) as precursors.

Related references:

Kalashnikov K.Ya., Shapiro I.D. 1962. Pests and diseases of maize. Leningrad: Sel.khozgiz, 189 p. (in Russian).
Nemlienko F.E. 1957. Diseases of corn. Moscow: Sel.khozgiz. 230 p. (in Russian).

© Levitin M.M.