Cerebella andropogonis blight

Cerebella andropogonis is a fungal pathogen that manifests as a characteristic blight on various grass species. It is widely recognized by researchers as a saprophytic or weakly parasitic fungus that thrives on the honeydew produced by other pathogens, primarily ergot (Claviceps species), colonizing the inflorescences of infected grasses.

The host range of this fungus primarily includes various cereal crops and wild grasses, with sorghum and sudangrass being the most frequently reported targets. Because the fungus depends on the sugary exudates produced during earlier stages of infection by other fungi, the occurrence of Cerebella is a strong indicator of prior pest pressure in the field.

The primary symptom of this condition is the development of black, convoluted, and firm stromatic tissues on the spikelets of the grass. These formations, which can appear lobed or brain-like, effectively cover the infected parts of the inflorescence. This unique physical appearance makes identification relatively straightforward during the late stages of crop development.

Environmental conditions that favor the spread of Cerebella andropogonis are characterized by warm, humid weather, especially during the flowering stage of the host plant. High moisture levels facilitate the growth of the fungus and the persistence of the sugary exudates required for its colonization, leading to potential outbreaks in areas with poor airflow and high rainfall.

Management and prevention of this condition focus on reducing the primary inoculum source and creating an unfavorable environment for fungal growth:

• Implementing crop rotation to break the cycle of infection.
• Ensuring seed purity to prevent the introduction of ergot sclerotia.
• Managing wild grass populations in and around fields to remove alternative hosts.
• Applying fungicides to control the primary fungal pathogens that secrete honeydew.
• Deep tillage practices to bury crop residues post-harvest.