Nineteen isolates of Rhizoctonia solani were found to be associated with root rot symptoms of guar plants collected from different fields located at New Valley Governorate, Egypt. All the obtained isolates were able to attack guar plants (cv. Local) causing damping-off and root rot diseases. Rhizoctonia solani isolate No. 8 (RG8) was the most virulent one in the pathogenicity tests. Salicylic acid (SA) and Pseudomonas fluorescens (PF) were examined individually or in combination in vitro and in vivo for controlling damping-off and root rot as well as growth promotion of guar plants. Activity of defence-related enzymes, including peroxidase (PO), polyphenol oxidase (PPO), phenylalanine ammonia lyase (PAL), pathogenesis related (PR) protein (chitinase and β 1,3 gluconase), were also studied in inoculated and non-inoculated guar plants treated with SA and P. fluorescens either individually or in combination, during the experimental period.