Acrasiales

Acrasiales represent a group of organisms belonging to the class of slime molds (myxomycetes). In an agronomic context, they are recognized as specific soil-borne pathogens that, under certain environmental conditions, can infect the root systems or aerial parts of plants that come into contact with moist soil.

The pathogens of the disease are unicellular amoeboid organisms. During their life cycle, they are capable of aggregation to form a pseudoplasmodium, which subsequently produces spore-bearing structures. This type of disease is often classified as a myxomycosis, primarily affecting tissues in a state of dormancy or weakened vegetative organs.

These organisms most frequently affect the seedlings of vegetable crops, ornamental plants, and various cereal species grown in waterlogged soils. The pathogen enters plant tissues through micro-cracks or mechanical injuries caused by cultivation practices or pests.

The primary symptoms of infection include the appearance of characteristic slimy coatings, darkening, and subsequent softening of plant tissues. In the infected zone, necrosis occurs, which spreads rapidly under high humidity conditions, leading to the decay of the root collar or the stem of the plant.

High soil moisture and moderate temperatures are critical for the development of Acrasiales. Spore dissemination occurs through irrigation water, contaminated farming equipment, or infected substrate particles. Protection and prevention measures include:

• Ensuring optimal drainage and soil aeration.
• Adherence to crop rotation and spatial isolation in nurseries.
• Conducting disinfection of soil and seeds.
• Application of broad-spectrum fungicides upon the first signs of disease.