Seedling or seed rot

The causative agent of this disease is the fungus Aspergillus flavus, a common soil-borne saprophyte that acts as an opportunistic pathogen. It belongs to the group of diseases that cause seed decay and seedling blight, significantly reducing stand establishment in agricultural fields.

This pathogen affects a wide range of crops, with particular concern for legumes such as chickpeas, as well as corn and various oilseeds. Susceptibility is highest when seeds have damaged seed coats, are of low vigor, or are exposed to adverse environmental conditions during the initial germination phase.

Symptoms are characterized by the development of a distinct yellow-green or olive-colored powdery mold on the surface of the seeds. Infected seeds fail to germinate or produce weak, discolored seedlings that quickly collapse due to decay of the hypocotyl, leading to visible gaps in the crop rows.

The development and spread of Aspergillus flavus are favored by high temperatures (typically between 25°C and 35°C) combined with high soil moisture. In storage conditions, high relative humidity and poor ventilation are the primary drivers for the rapid proliferation of the fungal colonies.

The economic impact of this disease is significant, resulting in poor crop stands and reduced yields. Furthermore, the fungus is known to produce aflatoxins, which are highly toxic metabolites, rendering the harvested grain potentially dangerous for both human consumption and livestock feed.

• Treat seeds with high-quality fungicides before planting.
• Maintain seed moisture levels below 12-14% during storage.
• Avoid mechanical damage to seeds during harvest and cleaning.
• Practice crop rotation to minimize the build-up of inoculum in the soil.