Desmosorus

The main symptom of Desmosorus infection is the deformation of the inflorescences (spikelets) of the host plant, which turn into spore masses.

Externally, the affected parts of the plant often take on a dark color due to the formation of hundreds of thousands of small fungal spores beneath the epidermis.

During maturation, the spikelet membrane ruptures, releasing a large quantity of spores that are wind-dispersed to neighboring healthy plants.

Infected individuals often appear stunted, their growth slows down, and the plant itself becomes incapable of producing normal fruit.

Visually, the disease becomes clearly noticeable during the heading phase, when healthy ears contrast with the organs affected by the pathogen.

The disease is caused by the fungus Desmosorus (primarily Desmosorus anthoxanthi), which belongs to the smut fungi group that affects cereal crops.

This microscopic pathogen specializes in infecting the reproductive organs of plants, leading to significant yield losses in terms of seed production.

The biological cycle of the fungus is closely linked to the development of the host, with the mycelium spreading inside tissues and replacing healthy structures.

The pathogen reproduces via teliospores, which can remain viable in the soil or on plant debris for an extended period.

The fungus shows a high degree of host specificity, limiting itself to a narrow range of grass species in the wild and in cultivated fields.

The development of Desmosorus is favored by high humidity and moderate temperatures during the formation of reproductive organs in cereals.

Frequent rainfall during the flowering phase facilitates mass infection, as spores penetrate the plant ovary more easily under these conditions.

The infection background increases significantly when crops are grown in monoculture, where the pathogen has the opportunity to accumulate in the soil.

Dense crop stands, which contribute to moisture stagnation and poor air circulation, create an ideal environment for the rapid spread of the fungus.

Minimum tillage can also contribute to the preservation of spores on the surface, which increases the risk of infecting subsequent generations of plants.

The primary damage caused by Desmosorus is the direct loss of seed productivity, as the affected organs fail to produce viable grains.

Large-scale infection of fields can reduce the yield of seed plots by a significant percentage, making such produce unusable.

The presence of infection in seed material poses a threat of rapid disease spread over large areas in subsequent seasons.

Damaged plants may be more susceptible to other secondary infections due to weakened immunity and metabolic disturbances.

Economic losses also increase due to the costs of implementing additional phytosanitary measures and the culling of contaminated raw materials.

The basis of controlling Desmosorus is the use of high-quality, healthy seed material that is free from fungal spores.

An effective preventive method is following proper crop rotation, which excludes the continuous cultivation of susceptible cereal crops.

Seed dressing with modern systemic fungicides allows for the destruction of both surface and latent infections before sowing.

Deep plowing and proper incorporation of plant debris help accelerate the death of spores located in the soil.

• Removal of infected plants from fields at early stages.
• Use of varieties resistant to smut diseases.
• Timely plant fertilization to strengthen their natural defense mechanisms.