Milo disease

Milo disease is a severe fungal disorder of sorghum caused by the soil-borne pathogen Periconia circinata. This fungus primarily attacks the root system and the lower vascular tissues, significantly compromising the physiological health of the sorghum crop.

Sorghum is the primary host for this pathogen. The disease is characterized by the production of a host-specific toxin known as pericoccin, which destroys the cell membranes of susceptible plant tissues. This results in systemic wilting and root dysfunction, making the plant unable to sustain itself even with optimal irrigation.

Key symptoms include stunting, chlorosis of lower leaves, and necrosis of the root system. As the disease progresses, the plant exhibits signs of severe water stress, followed by a gradual yellowing that moves upward. In many cases, infected stalks become brittle at the base, leading to significant lodging problems in the field.

The development of Milo disease is favored by warm soil temperatures and the presence of the pathogen in the crop debris. Periconia circinata can persist in the soil for extended periods as chlamydospores, waiting for a suitable host to germinate and initiate a new cycle of infection in subsequent seasons.

Management and prevention focus primarily on the use of resistant sorghum hybrids, which is the most reliable strategy to prevent economic losses. Cultural practices such as crop rotation and managing crop residue are also essential to reduce the inoculum density in the soil and mitigate the impact of the disease on susceptible fields.

• Stunting and stunted root growth.
• Yellowing and wilting of the leaf foliage.
• Darkening and decay of the root system.
• Premature death of the sorghum plants.
• Increased risk of lodging before harvest.