Streptomyces lydicus strain WYEC 108

Streptomyces lydicus strain WYEC 108 is a specialized strain of actinomycetes that acts as a natural antagonist to various plant pathogens. These beneficial bacteria colonize the rhizosphere, effectively forming a biological shield around the plant's root system.

During their metabolic activity, this strain produces unique enzymes and bioactive compounds capable of degrading the cell walls of fungal pathogens. This action prevents the infection from penetrating plant tissues and suppresses the development of fungal mycelium.

Beyond direct suppression, the strain triggers systemic acquired resistance (SAR) in plants, preparing them to defend against stress and biotic attacks. The plant increases its production of natural defensive compounds when exposed to this strain.

The bacteria engage in fierce competition for nutrients and physical space within the soil environment, successfully displacing harmful microorganisms. This competitive exclusion is a cornerstone of the biological control provided by this strain.

Additionally, the bacteria promote the mineralization of organic matter, improving the availability of essential nutrients. This dual action makes WYEC 108 both an effective biofungicide and a valuable plant growth promoter.

The primary purpose of this agent is to control a broad spectrum of soil-borne infections that cause root and crown rot. Its effectiveness has been demonstrated against Fusarium and Pythium wilts at various developmental stages.

The preparation is highly effective in suppressing Phytophthora and other fungal diseases that affect the lower parts of crops. It is particularly valuable in greenhouse settings where soil pathogen pressure is typically very high.

The agent is also effective against powdery mildew and various leaf spots that develop on aerial plant parts under humid conditions conducive to fungal growth.

It is commonly used to protect vegetables, berries, and ornamental crops, which are highly susceptible to soil pathogens during seed germination and early transplanting stages.

• Fusarium wilt
• Pythium root rot
• Rhizoctonia
• Powdery mildew

Application rates depend on the crop type and the chosen method of treatment. Preventive applications during seeding or transplanting are recommended for optimal control and establishment.

For seed treatment, a suspension of the preparation is used to coat the seed surface with beneficial spores. This creates an immediate protective layer for the developing embryo and radicle.

When applying as a soil drench, ensure uniform distribution within the root zone. Repeated treatments every 14 to 21 days are generally recommended, depending on the site's disease pressure.

Biological agents require adequate moisture and favorable temperatures for successful colonization. The most significant effects are observed when the soil is kept consistently moist without extreme temperature fluctuations.

Consistent preventive usage is far more effective than curative measures. Treating plants before disease symptoms become visible ensures that the beneficial bacteria have established a stable population.

A major limitation is potential incompatibility with certain chemical fungicides, especially those with strong bactericidal action, which may inhibit the growth of the beneficial strain.

Mixing the bioagent with aggressive pesticides is not recommended without a compatibility test. A safety interval of at least 7–10 days between chemical and biological applications is strictly advised.

The preparation is sensitive to UV radiation, so foliar sprays should be applied during the early morning or evening hours to avoid direct sunlight exposure.

Working solutions should not be stored for long periods, as the viability of the bacteria decreases rapidly outside of its stabilized environment. The mixture should be used immediately after preparation.

Standard safety measures should be followed when handling biological products, including the use of gloves and protective clothing to avoid skin and eye contact with the concentrate.