Seed coating is the most frequently used method in application of bio-fertilizers in different crops. The treatment of seeds with fungicides for storage purposes or protection during germination represents a challenge for application of bio-fertilizers by seed coating. In the current work, the antibacterial properties of five commercial fungicides known to be used in seed protection were screened against ten bacterial strains used as bio-fertilizers (Azotobacter salinestris, Azospirillum brasilense, Azospirillum lipoferum, Enterobacter cloacae, Rhizobium leguminosarum , Rhizobium phaseoli, Bacillus subtilis, Bacillus amyloliquefaciens, Paenibacillus polymyxa, Bacillus aryabhattai ) in addition, commercial sugar beet seeds dressed with unknown fungicids were also tested and the fungicide with antibacterial activity was selected and identified using gas chromatography (GC) to be used in further work. Sugar beet Seeds treated with selected fungicide were coated with different materials (Talc powder, Biochar, Charcoal, Polyvinylpyrrolidone (PVP), Beet moss) with expected adsorption properties and the effect of this materials in protection of bio-fertilizes was studied in agar plates. The most promising treatments were applied in a pot experiment using sugar beet (Beta vulgaris) seeds. The growth of most bacterial strains was not inhibited by already known fungicides except Rhizobium phaseoli which was inhibited by Tebuconasole 2.5% while one unknown fungicide showed a remarkable antibacterial activity against most bacterial strains under study. The GC-MS identification revealed that this fungicide is thiram. The most effective material in protection of microbial strain was charcoal.