Rule of Rhizobia and Bacillus in phytoremediation of contaminated soil with diesel oil

Oil pollution is one of the most dangerous pollutant due to the huge quantities that are spillage from crude oil that contains toxic compounds. To treat contaminated soil with oil, bioremediation is an important methods which involve use microorganisms and plants to degraded pollutants and clean up the soils. A biological pot factorial experiment was carried out in a (CRD) design to study the ability of Rhizobia species, a mixture of Bacillus and Grasspea leguminous plant for removal diesel oil from contaminated soil. The results showed that the different species of bacteria led to a significant increase in the amount of diesel oil absorbed by roots and shoots of plant for all treatments compared to the control treatment. And the Vigna radiata (R4) species gave a highest value (13.70 mLpot⁻¹) absorbed by shoots compared to lowest value of control treatment (4.15 mLpot⁻¹), with a significant increase about (230.12%). The diesel oil amounts remaining in soil were decreased significantly with the addition of different isolates of Rhizobium bacteria or Bacillus compared to the control treatment. Moreover, there were significant differences in the amount of diesel oil degraded in soil treated with different isolates of microbial treatments planted compared to control treatment. The adding Rhizobia isolated from Vicia faba (R2) recorded the highest amount decomposed (504.33) mLpot⁻¹ compared to the control treatment (318.52) mLpot⁻¹ with a significant increase (58.33%). Therefore, we concluded that the Grasspea plant with Rhizobia species or Bacillus can be used for phytoremediation contaminated soil with diesel oil.