Chrysosporium rot

Chrysosporium rot is a fungal infection caused by species within the Chrysosporium genus. These fungi are ubiquitous in soil environments and typically function as saprotrophs, but they can become opportunistic pathogens when plants are weakened, stressed, or stored under improper conditions.

The host range is broad, but the disease is particularly notorious for damaging bulbs, corms, and seeds in storage. Furthermore, Chrysosporium can infect a variety of crops in the field if they are already compromised by other pests, mechanical injuries, or adverse environmental factors such as excessive moisture.

Symptoms appear as a distinct moldy growth on the plant surface, often described as a white, yellow, or tan powdery substance. Beneath this growth, the host tissue typically exhibits signs of soft decay, necrosis, and a foul, musty odor, leading to significant post-harvest losses and reduced germination rates in seeds.

The development of the pathogen is highly dependent on humidity levels and airflow. It thrives in stagnant, humid environments where the temperature allows for rapid mycelial expansion. Since the fungus produces numerous conidia, it can easily spread throughout a storage facility, contaminating crates, tools, and healthy plant material.

To control and prevent Chrysosporium, it is essential to prioritize hygiene and environmental control. This includes maintaining low humidity in storage areas, removing decaying debris from fields, and treating seeds with appropriate chemical fungicides. Regular monitoring and the immediate removal of infected specimens are vital to prevent the secondary spread of the disease.