This study is concerning with searching use of the phenomenon of systemic acquired resistance (SAR) to control plant viruses and increased growth in vitro. Through this study, it was and proved to induced SAR in potato plants using bacterial and fungal contaminants in tissue culture against Potato virus Y. These biotic inducers were Pseudomonas sp., Bacillus sp., Xanthomonas sp. as well as Trichoderma, Aspergillus and Fusarium as contaminants microbial of potato micropropagative in vitro. The occurrence of induced resistance and increased potato plantlets were found by MS medium treated with culture filtrates based on reduction of PVY infection, disease severity, biochemical changes accompanied to induced resistance (the high level of endogenous salicylic acid, protein content, chlorophyll contents and peroxidase and polyphenol oxidase activities as well as increasing in growth parameters).