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<i>Streptomyces</i> species are effective biocontrol agents toward many plant pathogens. These microorganisms are well known for producing secondary metabolites, promoting plant growth and inducing plant defense mechanisms. In this study, the ability of tomato root-colonizing <i>Streptomyces</i> strains to trigger the resistance against <i>Rhizoctonia solani</i> (J.G. Kühn) AG4 was investigated. For this goal, we evaluated the pattern of <i>LOXB</i> and <i>PAL1</i> genes expression changes upon pathogen inoculation in primed tomato plants. The results revealed that <i>Streptomyces globisporous</i> (Krasil’nikov) strain F8 and <i>S. praecox</i> (Millard and Burr) strain R7 were able to enhance the expression of lipoxygenase and phenylalanine ammonia lyase in tomato plants. This finding suggests that <i>Streptomyces</i> strains F8 and R7 may trigger jasmonic acid and phenyl propanoid signaling pathways in plants, therefore, resulting an induced defense status in tomatoes against <i>R. solani</i>. Biochemical characterization of these <i>Streptomyces</i> strains showed that they were strong producers of siderophores. <i>S. praecox</i> strain R7 produced siderophores of hyderoxamate and catechol types and <i>S. globisporous</i> strain F8 produced a phenolic siderophore. Moreover, they also produced protease while only the <i>S. praecox</i> strain R7 was able to produce amylase. Taken together, these results indicate that <i>S. globisporous</i> strain F8 and <i>S. praecox</i> strain R7 promote plant growth and reduces disease and hence are suitable for future in depth and field studies with the aim to attain appropriate biocontrol agents to protect tomatoes against <i>R. solani</i>.