Eyespot fungus

Ramulispora herpotrichoides (formerly Pseudocercosporella herpotrichoides) is a specialized fungal pathogen belonging to the kingdom Fungi, known as the primary causal agent of eyespot disease in cereals. This disease significantly impacts the base of the stems in various grain crops, leading to lodging and reduced grain quality.

Major host plants for this pathogen include winter wheat, barley, and rye. The fungus colonizes the stem base, creating diagnostic lesions often referred to as "eyespot" symptoms. As the infection progresses, the structural integrity of the stem is compromised, which often results in premature lodging of the crop before harvest.

The biological cycle of the fungus is characterized by survival on crop debris (straw and stubble) left in the field. During cool and wet conditions in autumn and spring, the pathogen produces conidia. These spores are splash-dispersed by rain onto the stems of emerging seedlings, initiating the infection process.

Environmental conditions play a crucial role in the development of the disease. Ramulispora herpotrichoides thrives in temperate climates with high humidity and temperatures between +5°C and +15°C. Dense stands and continuous cropping of susceptible varieties significantly increase the risk of an epidemic.

Control and management strategies are essential for minimizing yield loss:

• Implementing crop rotation with non-host species to break the pathogen's life cycle.
• Selecting resistant or tolerant cultivars suitable for specific growing regions.
• Managing crop residues through deep tillage or accelerated decomposition.
• Applying targeted fungicides during the early growth stages if the disease threshold is exceeded.