Myco-phytoremediation of arsenic- and lead-contaminated soils by Helianthus annuus and wood rot fungi, Trichoderma sp. isolated from decayed wood

• Published in: Ecotoxicology and environmental safety 2018-04, Vol.151, p.279-284
• Main Authors: Govarthanan, M., Mythili, R., Selvankumar, T., Kamala-Kannan, S., Kim, H.
• Format: Article
• Language: English
• Subjects: Arsenic; Helianthus annuus; Phytoremediation; Soil enzymes; Trichoderma
• ISSN: 0147-6513; 1090-2414
• DOI: 10.1016/j.ecoenv.2018.01.020

In the present study, Helianthus annuus grown in arsenic- (As) and lead- (Pb) contaminated soil were treated with plant-growth promoting fungi Trichoderma sp. MG isolated from decayed wood and assessed for their phytoremediation efficiency. The isolate MG exhibited a high tolerance to As (650mg/L) and Pb (500mg/L), and could remove > 70% of metals in aqueous solution with an initial concentration of 100mg/L each. In addition, the isolate MG was screened for plant-growth-promoting factors such as siderophores, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, indole acetic acid (IAA) synthesis, and phosphate solubilisation. Phytoremediation studies indicated that treatment of H. annuus with the isolate MG had the maximum metal-accumulation in shoots (As; 67%, Pb; 59%). Furthermore, a significant increase in the soil extracellular enzyme-activities was observed in myco-phytoremediated soils. The activities of phosphatase (35 U/g dry soil), dehydrogenase (41mg TPF/g soil), cellulase (37.2mg glucose/g/2h), urease (55.4mgN/g soil/2h), amylase (49.3mg glucose/g/2h) and invertase (45.3mg glucose/g/2h) significantly increased by 12%, 14%, 12%, 22%, 19% and 14% in As contaminated soil, respectively. Similarly, the activities of phosphatase (31.4U/g dry soil), dehydrogenase (39.3mg TPF/g soil), cellulase (37.1mg glucose/g/2h), urease (49.8mgN/g soil/2h), amylase (46.3mg glucose/g/2h), and invertase (42.1mg glucose/g/2h) significantly increased by 11%, 15%, 11%, 18%, 20% and 14% in Pb contaminated soil, respectively. Obtained results indicate that the isolate MG could be a potential strain for myco-phytoremediation of As and Pb contaminated soil. •Wood rot arsenic and lead resistant Trichoderma sp. MG was isolated from decayed wood.•Inoculation of Trichoderma sp. MG improved Helianthus annuus growth by producing plant growth promoting factors.•Increased soil enzyme activities were observed in myco-phytoremediated soil.•The isolate Trichoderma sp. MG could be applied into the future remediation of As and Pb contaminated soil.