EFFICIENCY OF TWO BACTERIAL STRAINS, Bacillus subtilis BS2 AND B. mycoides BM7, ISOLATED FROM PETROLEUM - POLLUTED LANDS FOR BIOREMEDIATION OF HYDROCARBONS-POLLUTED SOIL IN SAUDI ARABIA

Abstract

The efficiency of two bacterial strains, namely: Bacillus subtilis Bs2 and B. mycoides Bm7 that have been previously isolated from petroleum-polluted soil in Saudi Arabia, for bioremediation of hydrocarbons-polluted soil were studied. The results indicated that both bacterial strains played an influential role in elimination of the phytotoxicity of benzene and toluene as evidenced by the pronounced increments in percentages of grain germination and viability of emerged seedlings, chlorophylls and carotenoids pigments contents of leaves as well as the significant improvement in plant growth vigor (root length, plant height and biomass gain) of barley (Hordeum vulgare L.) "Madini" cultivar as compared to that cultivated in untreated hydrocarbonpolluted soil under the same environmental conditions. However, B. subtilis Bs2 proved by far to surpass B. mycoides Bm7 in its bioremediation potential.