Streptomyces lydicus is a naturally occurring bacterium that is commonly found in soil. When applied to soil mixes or turf grass, the bacterium protects the plant against a range of root decay fungi.
Streptomyces lydicus can also be applied to plant foliage to control powdery mildew.
The bacterium works by colonizing the growing root tips of plants and parasitizing root decay fungi (such as Fusarium, Pythium, and other species). The bacterium may also produce antibiotics that act against these fungi.