Cochliobolus carbonum

Cochliobolus carbonum (anamorph: Helminthosporium carbonum) is one of more than 40 species of filamentous ascomycetes belonging to the genus Cochliobolus (anamorph: Bipolaris/Curvularia). This pathogen has a worldwide distribution, with reports from Australia, Brazil, Cambodia, Canada, China, Congo, Denmark, Egypt, India, Kenya, New Zealand, Nigeria, Solomon Islands, and the United States. Cochliobolus carbonum is one of the most aggressive members of this genus infecting sorghum (Sorghum spp. [Poaceae]), corn (Zea mays [Poaceae]) and apple (Malus domestica [Rosaceae]). As one of the most devastating pathogens of sweet corn, C. carbonum causes Northern leaf spot and ear rot disease while the ****ual stage causes Helminthosporium corn leaf spot. Cochliobolus carbonum is pathogenic to all organs of the corn plant including root, stalk, ear, kernel, and sheath. However, symptoms of infection show distinct manifestations in different plant parts: whole plant - seedling blight affects the whole plant, leaf discoloration and mycelial growth, black fungal spores and lesions appear on inflorescences and glumes, and grain covered with very dark brown to black mycelium which gives a characteristic charcoal appearance due to the production of conidia.