Aspergillus japonicus

Aspergillus japonicus is a filamentous fungus belonging to the genus Aspergillus, recognized as a significant post-harvest pathogen that causes rot in various fruits and vegetables. As a facultative parasite, it thrives on decaying plant material but readily infects healthy produce upon encountering minor physical injuries or environmental stress.

The host range of this fungus is extensive, commonly affecting onion bulbs, garlic, citrus fruits, and pome fruits. Its ability to colonize host tissues rapidly makes it a major concern for growers and storage facility managers, as it can cause substantial economic losses within a very short period of time.

The primary symptom of infection is the development of dense, dark-brown or black powdery spore masses on the surface of the affected plant tissue. This surface growth is accompanied by tissue softening and tissue degradation, resulting in a watery rot and a distinct, musty odor that renders the crop unmarketable.

Development and spread are primarily driven by high relative humidity and warm temperatures. While the optimal range for the pathogen's growth is often between 25 and 30 degrees Celsius, it is highly resilient and can remain latent in storage environments for extended periods, waiting for favorable conditions to proliferate.

Integrated management is essential for control, starting with careful handling during harvest to minimize wounds. Post-harvest strategies include thorough drying of produce before storage, maintenance of low relative humidity, and proper aeration within storage facilities. Regular inspection and prompt removal of infected units prevent the rapid spread of spores within the stored lot.

• Minimize mechanical damage during harvest
• Proper post-harvest drying
• Maintaining optimal airflow in storage
• Regular sanitation of storage containers