Streptomyces murinus

Streptomyces murinus is a species of actinobacteria identified in agricultural research as a potential phytopathogen capable of causing necrotic lesions and rot in various root and tuber crops. While many streptomycetes are beneficial, specific strains of this species can compromise plant health and yield quality.

The causative agent belongs to the genus Streptomyces, characterized by a complex mycelial structure. The disease type is primarily associated with bacterial rot or common scab-like symptoms. Through the secretion of potent hydrolytic enzymes, the bacteria break down plant tissue cells, facilitating their colonization and nutrient uptake.

The disease primarily affects crops such as potatoes, sugar beets, and carrots. Infection usually occurs through the rhizosphere, entering the plant via cracks, lenticels, or injuries caused by mechanical tillage and soil pests. Once established, the pathogen weakens the root system, inhibiting the plant's ability to absorb water and nutrients.

Symptoms include visible lesions, dark spots, or deep cracks on the surface of roots and tubers. In severe cases, the infected tissue becomes soft and necrotic, significantly reducing the marketability and shelf life of the produce. Foliar symptoms may include stunted growth and premature yellowing of the leaves due to impaired root function.

The development of Streptomyces murinus is favored by warm, well-aerated soils with moderate moisture levels. Because the bacteria can survive in soil debris for several seasons, prevention is critical. Effective management requires an integrated approach focusing on cultural practices and maintaining optimal soil conditions to suppress the pathogen's activity.

• Implementation of long-term crop rotation schemes.
• Application of lime to adjust soil pH to unfavorable levels for the pathogen.
• Ensuring proper soil drainage and moisture control.
• Use of antagonistic biological agents to suppress bacterial populations.