Petroleum hydrocarbon rhizoremediation and soil microbial activity improvement via cluster root formation by wild proteaceae plant species

Rhizoremediation potential of different wild plant species for total (aliphatic) petroleum hydrocarbon (TPH)-contaminated soils was investigated. Three-week-old seedlings Acacia inaequilatera, pyrifolia, stellaticeps, Banksia seminuda, Chloris truncata, Hakea prostrata, Hardenbergia violacea, and Triodia wiseana were transplanted in a soil contaminated with diesel engine oil as TPH at pollution levels 4,370 (TPH1) 7,500 (TPH2) mg kg−1, an uncontaminated control (TPH0). After 150 days, the presence negatively affected growth, but growth inhibition effect varied between species. Plant associated root biomass influenced activity rhizo-microbiome. The B. C. H. prostrata significantly increased removal rate (up to 30% compared unplanted treatment) due stimulation rhizosphere microorganisms. No significant difference observed TPH1 TPH2 regarding tolerance rhizoremediation potentials three stimulated cluster formation seminuda which enhanced remediation these two members Proteaceae family. These results indicated that could be suitable candidates TPH-contaminated soil.