Mortierella mutabilis

Mortierella mutabilis is a soil-inhabiting fungus belonging to the Mortierellaceae family. While many fungi in this genus are common decomposers, Mortierella mutabilis is recognized in agricultural science as a pathogen that can contribute to root rot complexes, significantly affecting plant health in damp soil environments.

The disease is primarily characterized as a soil-borne root infection. It acts by colonizing the rhizosphere and invading the root cortex, which disrupts the plant's ability to uptake water and essential minerals. This leads to a decline in physiological performance, especially during the early growth stages of the plant cycle.

This fungus predominantly affects young seedlings in greenhouses, vegetable crops, and ornamental plants. It is particularly dangerous in high-humidity cultivation systems where soil aeration is limited, providing an ideal microclimate for the fungus to proliferate and attack vulnerable root systems.

Key symptoms of an infestation include:

• darkening and softening of the roots;
• stunted growth and loss of vigor;
• wilting of seedlings despite moist soil conditions;
• development of a grayish mycelial mat on the soil surface near the stem base.

Effective prevention and control require a multi-faceted approach. Key practices include improving soil drainage, ensuring proper crop rotation, and using sterilized growing media in greenhouses. Chemical control involves the application of appropriate soil fungicides, while biological control methods using beneficial bacteria can help suppress the population of the pathogen.