Penicillium rot

Penicillium pinophilum is a filamentous fungal pathogen responsible for Penicillium rot and seed decay in a wide range of agricultural crops. As a pervasive environmental fungus, it primarily acts as a facultative parasite, attacking plants that are experiencing physiological stress or have suffered mechanical damage during harvest and storage.

This pathogen demonstrates a broad host range, infecting seeds of cereals, legumes, and various fruits and vegetables. When infecting seeds, the fungus penetrates the protective outer layers, colonizing the embryo and endosperm. This results in pre-emergence damping-off or the development of weak seedlings, which significantly impacts overall crop establishment and yield potential.

The diagnostic symptoms of the disease include the appearance of a dusty, blue-green, grey-green, or olive-colored mycelial growth on the surface of seeds or fruits. Infected tissues usually become soft, discolored, and watery. In storage environments, this fungus can rapidly spread from infected units to healthy ones, leading to massive post-harvest losses and reduced marketability.

Environmental conditions play a crucial role in disease epidemiology. The fungus thrives in conditions of high relative humidity (above 75%) and moderate temperatures ranging from 15°C to 25°C. The accumulation of moisture on crop surfaces, often caused by poor ventilation or temperature fluctuations during storage, provides an ideal environment for spore germination and colonization.

Integrated management is essential for controlling Penicillium rot. Key strategies include:

• treating seeds with effective systemic fungicides before planting;
• ensuring crops are harvested at optimal moisture content;
• providing adequate ventilation in storage facilities to prevent moisture buildup;
• minimizing mechanical damage during harvest to prevent entry points for the pathogen.