Tricholomosis of bulbous plants

The primary sign of infection is the emergence of a distinctive white or gray felt-like mycelium on the basal plate of the bulb, which gradually spreads to the outer scales.

Above-ground parts of the plant begin to show signs of stunted growth, with foliage losing turgor and yellowing, starting from the tips downward.

The root system of infected plants becomes brittle, darkens in color, and eventually decays, which makes the bulb easy to pull out of the soil.

When cutting into the bulb, one can observe softened tissues with watery patches, often accompanied by an unpleasant putrid odor.

In the final stages of the disease, the scales of the bulb are completely degraded, turning into a mushy mass covered with fungal threads.

The disease is caused by a pathogenic fungus of the genus Tricholoma, which acts as a semi-parasite on the subterranean organs of bulbous crops.

The fungus is capable of surviving in the soil for extended periods in the form of dormant spores or sclerotia, waiting for a suitable host.

Mycelium actively spreads upon contact with damaged plant tissues, entering through micro-cracks or wounds caused by pests or mechanical handling.

The disease is classified as a Fusarium-like rot that targets both the basal plate and the inner succulent scales of the bulb.

The pathogen is highly transmissible via infected planting material or through contaminated soil remnants left after the harvest season.

The most favorable conditions for the development of the pathogen are excessive soil moisture combined with moderately warm temperatures.

Waterlogging in the planting area, caused by poor drainage or heavy rainfall, significantly increases the risk of infection spreading to healthy bulbs.

A temperature range between 18 and 25 degrees Celsius is optimal for spore germination and rapid colonization of plant tissues by the mycelium.

Densely planted crops that restrict air circulation create a microclimate that facilitates the rapid progression of the fungal infection.

Heavy clay soils that retain moisture promote the development of rot much faster than lighter, well-drained sandy substrates.

The primary danger lies in the rapid progression of the disease during storage, which can lead to a loss of up to 70-80% of the total harvest.

The disease results in a significant reduction in quality, rendering the bulbs unsuitable for long-term storage or commercial sale.

In field conditions, severe infection leads to sparse plant stands, drastically reducing the total yield per unit area.

Infected planting material often fails to produce strong shoots or develops weak plants that cannot form large, healthy bulbs.

Soil contamination by the pathogen restricts the possibility of cultivating sensitive bulbous species on the same plot for several years.

The most critical measure is the strict inspection of planting material and the removal of any suspicious bulbs before they are put into the ground.

Strict adherence to crop rotation, avoiding the return of bulbous crops to the same area for at least 4-5 years, helps lower infection levels.

Deep plowing and thorough clearing of plant debris from the field after harvest are essential to minimize the pathogen load in the soil.

• Treatment of bulbs with systemic fungicides before planting.
• Control of soil-borne pests that cause damage to the basal plates.
• Maintenance of a dry, well-ventilated storage environment for the harvested crop.

Upon detection of infection, affected plants must be removed immediately along with the surrounding soil to prevent the spread of spores.