Eyespot of cereals

The fungus Oculimacula acuformis is a significant plant pathogen responsible for causing eyespot disease in various cereal crops. This pathogen, classified within the Oculimacula genus, specifically targets the stem bases of cereals, leading to the development of necrotic lesions that disrupt the plant's vascular integrity.

The disease primarily affects winter wheat, winter barley, rye, and triticale. It is particularly prevalent in regions with temperate climates where winter cereal production is intensive, as the fungus thrives during the extended, cool, and humid growing seasons that allow for prolonged interaction between the pathogen and the host plant.

Typical symptoms are identified by the presence of elliptical spots on the stem bases, characterized by a light-colored center surrounded by a dark margin, resembling an eye. As the infection progresses, the structural integrity of the stem weakens, causing the crop to lodge prematurely, which hinders nutrient transport and results in thin, poorly developed grain heads.

The development and spread of Oculimacula acuformis are favored by cool, wet conditions, especially during the autumn emergence and early spring regrowth phases. The fungus overwinters on infected crop residues in the soil, which serve as the primary source of inoculum for subsequent seasons, facilitating the spread of spores through rain splash to nearby healthy plants.

Economic damage caused by eyespot is significant, often manifesting as reduced grain yield and quality due to severe lodging. Effective management strategies involve a combination of cultural practices, such as crop rotation to break the cycle of infection, and the judicious use of systemic fungicides applied at the stem elongation stage to mitigate the impact of the disease.

• Implementing diverse crop rotation cycles.
• Managing crop residues to reduce primary inoculum.
• Applying fungicides during the early stem elongation phase.
• Selecting cultivars with improved genetic resistance to eyespot.