It has been shown that fertilizers and biological controllers based on beneficial microorganism producing metabolites induce plant growth and act against pathogens and pests that affect agro ecosystems. Therefore, its use constitutes an efficient practice of clean production that allows to reduce the environmental impact caused by the use of agrochemicals. In this work, we investigated the antagonistic and chitinolytic activity of 15 strains of bacteria and one yeast, isolated from lignocellulosic residues of castor ( Ricinus communis ).The antagonistic activity of each strain was evaluated on the basis of the ability to inhibit the growth of the plant pathogen fungus Fusarium equiseti , in PDA culture. Only the Bacillus subtilis showed a significant inhibition of the fungus growth, and it was 76,08%. Therefore, the Bacillus subtilis strain can be used in the development of microbial inoculants. The chitinolytic capacity of the strains was defined on the basis on the fungus growth and the development of hydrolysis halos around the colonies, in a colloidal chitin based culture. None of the strains showed ability to degrade chitin.