Ascotricha chartarum

The fungus Ascotricha chartarum is an ascomycete pathogen known to cause degradation of plant tissues and seed decay. While often classified as a saprophyte that lives on dead organic matter, it can act as a secondary pathogen, exploiting physiological stress or environmental weakness in various host plants to establish infection.

A diverse range of crops can be affected by this fungus, including cereals, legumes, and various vegetable species. It is particularly notorious in storage facilities where it compromises seed quality and viability. In field conditions, it can infect weakened plants, affecting both foliage and reproductive structures during periods of high humidity.

Symptoms are typically characterized by the appearance of dark olive or black, velvety fungal colonies on the host tissue. On seeds, this presents as a dusting of mold that inhibits germination. When affecting leaves or stems, it causes chlorosis or necrosis, eventually leading to the formation of visible fruiting bodies of the fungus.

The development and spread of Ascotricha chartarum are driven by high environmental humidity and moderate temperatures. The fungus produces abundant conidia that are dispersed via wind, water splash, and human activity. Once established, the pathogen can survive for long periods in crop residues or contaminated soil, serving as a primary inoculum source.

Effective management requires a multi-faceted approach. Key practices include:

• Maintaining proper storage hygiene and keeping seed moisture below critical levels.
• Ensuring optimal air circulation in greenhouses and fields to reduce humidity.
• Using high-quality, fungicide-treated seeds.
• Removing and destroying infected plant debris after harvest to prevent survival.
• Rotating crops to break the pathogen's life cycle.