Anthracnose of pepper

The disease known as anthracnose is caused by the pathogenic fungus Colletotrichum piperis. This organism belongs to the group of Ascomycetes and is a significant threat to global pepper production, often causing severe fruit rot and post-harvest losses that render the produce unsalable in both local and international markets.

This fungus predominantly infects plants in the Solanaceae family, specifically focusing on sweet and hot peppers. It is known to affect all parts of the plant, including stems, leaves, and particularly the fruit. The pathogen acts as both a seed-borne and soil-borne threat, persisting in crop debris and infected seeds, which allows it to cycle through successive growing seasons.

The visual symptoms of Colletotrichum piperis infection typically manifest as sunken, water-soaked lesions on the surface of the pepper fruit. As these lesions mature, they darken in color and often form distinct concentric circles. Small black structures, known as acervuli, develop within these lesions, and under humid conditions, they produce salmon-colored or pink spore masses.

Environmental conditions play a critical role in the epidemiology of the disease. The pathogen thrives in warm temperatures (ideally between 20°C and 28°C) combined with high relative humidity or prolonged periods of rainfall. Spores are primarily disseminated by water splashes, wind, and movement of contaminated tools or workers through the field, leading to rapid disease spread in high-density plantings.

Managing this disease requires an integrated approach to minimize crop loss:

• Selection of disease-free, high-quality seeds for planting.
• Rigorous implementation of crop rotation cycles of at least three years.
• Field sanitation to remove and destroy all infected plant residues after harvest.
• Maintenance of proper plant spacing to facilitate airflow and reduce canopy humidity.
• Application of protective and systemic fungicides during the growing season based on monitoring and weather forecasting.