Eremotheciosis

The main sign of Eremotheciosis is so-called "internal decay" or specific seed discoloration. Externally, infected pods may look healthy, but when opened, deep defects are revealed.

Inside the seed, a change in tissue color is often observed, with the appearance of necrotic spots that can vary from yellowish to brown and dark gray, depending on the stage of fungal growth.

Infected seeds often lose their natural shape and become shriveled or deformed. A significant reduction in seed density is frequently noted, which is easily detected during seed calibration.

In humid weather, a faint fungal coating consisting of conidia may develop on the surface of pods or seeds. However, the disease is most often diagnosed only at the stage of post-harvest seed inspection.

An important symptom is also the reduction in seed germination energy and viability. Infected seeds either fail to sprout or produce weakened seedlings that quickly perish due to suppression by the pathogen.

The causative agent of the disease is the fungus Eremothecium coryli, which belongs to the Ascomycota division. This is a pathogenic microorganism capable of infecting the reproductive organs of plants, causing specific changes in the development of seeds and fruits.

The fungus leads a primarily parasitic lifestyle. Its life cycle is closely linked to insect pests, which act as the main vectors of the infection, transferring fungal spores from diseased plants to healthy tissues.

The pathogen's mycelium is capable of penetrating deep into the seed tissues, absorbing nutrients and destroying the embryo's structure. During its life cycle, the fungus secretes toxins that disrupt the normal metabolism of the host plant.

The fungus can develop both inside the seeds and on the surface of vegetative organs, but the most critical stage is the infection of pods and capsules during their formation and maturation.

The biology of Eremothecium coryli is studied as a dangerous factor in reducing seed quality, as the pathogen remains viable in dry seeds for a long period, maintaining its infectious potential.

The primary condition for the spread of Eremotheciosis is the presence of insect pests, such as mirid bugs, which pierce pods and introduce the infection. Without the activity of these pests, the spread of the disease is severely limited.

High humidity during the flowering and pod formation stages promotes more active development of the fungus, as spores require moisture for successful germination after being introduced by insects.

Optimal temperatures for the life activity of Eremothecium coryli lie within a moderately warm range, which coincides with the active vegetation phases of many agricultural crops, including soybeans and beans.

Poor agricultural practices that increase the population of phytophagous insects directly correlate with increased Eremotheciosis incidence in fields, turning the disease into an epiphytotic.

Continuous cropping of susceptible plants in a monoculture creates a stable infectious background, providing the pathogen with a constant food source and a place for spores to overwinter in plant debris.

The main danger of Eremotheciosis lies in the hidden nature of the disease, which means farmers may not be aware of the infection until harvest time. This leads to a significant loss of marketable produce.

The disease causes serious damage to seed quality. Infected soybean and other legume seeds become unsuitable for the food industry because their biochemical properties and organoleptic indicators are compromised.

A sharp drop in seed germination leads to sparse crop stands, forcing farmers to increase seeding rates or re-seed, which results in substantial economic losses.

Eremotheciosis complicates the export of agricultural products, as the presence of the pathogen in seed batches is a strict phytosanitary restriction in many countries around the world.

The consequences of the infection manifest not only in reduced yield mass but also in the accumulation of mycotoxins, which make the produce hazardous for feed purposes or food processing.

The primary protective measure is the control of insect vectors, particularly bugs. Timely insecticide applications during critical growth stages of the crop significantly reduce the risk of infection.

It is important to conduct careful selection of seed material. Using only healthy seeds that show no signs of infection is the foundation for reducing the primary infectious load in fields.

Adhering to crop rotation helps break the pathogen's life cycle and limit the population of insect pests. Rotating with crops not susceptible to this fungus species is recommended.

Destroying plant residues and deep plowing help reduce the infection reservoir, as the fungus can persist in post-harvest debris on the soil surface or in the upper soil layer.

Using fungicides for seed treatment can be effective if the pathogen is on the surface, but deep-seated seed infection requires a complex management approach and strict adherence to preventive measures.