Glomerella tucumanensis

Glomerella tucumanensis is an ascomycete fungus and the teleomorph stage of Colletotrichum falcatum. It is recognized globally as a serious plant pathogen specifically adapted to infecting sugarcane crops, leading to significant economic losses in the sugar industry.

The fungus is the causative agent of red rot, a devastating disease that primarily affects the stalks of sugarcane. As the mycelium colonizes the vascular tissues, it causes internal necrosis, characterized by a reddening of the tissues and the development of white patches, often accompanied by an alcoholic or sour odor due to fermentation.

The life cycle involves both sexual (ascospores) and asexual (conidia) stages. The pathogen survives in soil, crop debris, and systemically infected seed canes. Spores are primarily dispersed through rainwater, irrigation water, and wind. Insects feeding on the stems often act as vectors and create entry points for the fungus to penetrate the tough rind of the cane.

Development is most aggressive under warm and humid conditions, which favor sporulation and hyphal growth. The virulence of the pathogen results in a drastic reduction in sucrose content, poor germination of planting material, and stunted growth of the cane, which eventually leads to the death of the stool in susceptible cultivars.

Integrated management strategies are essential to mitigate the impact of the disease:

• using pathogen-free and certified disease-resistant sugarcane varieties;
• hot water treatment of seed setts before planting;
• implementing crop rotation with non-host crops to reduce inoculum levels in the soil;
• sanitation measures to remove and destroy infected stalks from the field;
• controlling borer insects to prevent mechanical entry points for the pathogen.