Aspergillus ochraceous

Systematic position and pathogen type. Aspergillus ochraceous belongs to the kingdom Fungi, phylum Ascomycota, and the genus Aspergillus. It is a filamentous mold fungus that exists primarily as a saprophyte, but acts as a significant pathogen during the post-harvest storage period of various crops.

Diseases and susceptible crops. This species is a primary cause of grain and seed molding. It affects a wide range of agricultural products, including cereal grains (wheat, corn, barley), legumes, oilseeds, nuts, and dried fruits. The infection process frequently occurs in storage environments where conditions favor fungal growth.

Biology and life cycle. The fungus reproduces through the production of numerous conidia (asexual spores), which are typically yellow or ochre-colored. These conidia are dispersed by wind, insects, and contaminated machinery. Upon landing on a suitable organic surface, the spores germinate and form mycelium, which penetrates the plant tissue to extract nutrients.

Conditions for development and harmfulness. Aspergillus ochraceous thrives in warm and humid conditions, typically requiring temperatures between +20°C and +30°C and substrate moisture levels above 15%. The primary risk factor is the production of mycotoxins, especially ochratoxin A, which is toxic to both humans and animals, posing a severe threat to food and feed safety.

Protection and control measures. Management of this pathogen requires a multi-faceted approach to storage:

• Drying crops to a safe moisture content immediately after harvest.
• Maintaining proper ventilation and temperature control in storage facilities.
• Cleaning grain to remove debris and damaged kernels that facilitate infection.
• Implementing regular monitoring for signs of heating or fungal growth in bulk.
• Applying recommended seed treatment fungicides to prevent early-stage infection.