Penicillium rot

The disease is caused by the microscopic filamentous fungus Penicillium velutinum. As a common mold, it resides in soil and organic matter, acting as both a saprophyte and a significant pathogen that attacks a wide range of agricultural crops, particularly during the post-harvest period.

This pathogen affects a diverse variety of crops, including cereals, legumes, and perishable produce like fruits and vegetables. Plants that have been weakened by environmental stress or physical damage are particularly susceptible, as the fungus easily penetrates tissues through even minor micro-cracks in the surface.

The primary clinical sign of the infection is the development of a dense, velvety fungal colony, which transitions from white to a characteristic blue-green or greyish hue. As the infection progresses, the plant tissue softens, becomes watery, and emits a distinct musty odor, resulting in total spoilage of the affected product.

The development of Penicillium velutinum is heavily dictated by high ambient humidity and moderate temperatures. When humidity exceeds 75% in storage facilities, the fungal spores germinate rapidly, leading to the formation of mold patches that can spread through the entire storage batch if not addressed promptly.

The economic damage caused by this fungus is severe, manifesting as significant losses in seed viability and the total destruction of stored harvested goods. Effective protection strategies include:

• Ensuring proper post-harvest drying to reduce moisture levels in seeds and grains.
• Maintaining optimal airflow and climate control in storage units to prevent condensation.
• Cleaning and disinfecting all storage containers and warehouse walls regularly.
• Treating seeds with appropriate fungicides to prevent early-stage infection during germination.