Mixed Metal Phytoremediation Potentials with Industrial Hemp Cannabis Sativa L

Lynda Peter, Tennessee State University


Phytoremediation emerged decades ago as an eco-friendly method for remediating soils contaminated with metals and their mixtures. Industrial hemp (IH) is increasingly recognized as an effective agent of phytoremediation of metal contaminants. A series of greenhouse experiments were conducted to determine the biomass and biochemical responses of IH grown in a soil (Armor silt loam, ASL) that was fortified with heavy metal mixtures of As, Cr and Cu. Preliminary experiments with IH varieties namely, Tygra (TY), Futura 75 (FT) and Eletta Compana (EC) identified TY as candidate with potentials for phytoremediating mixed heavy metal (MHM) contaminants. TY was grown in MHM-fortified ASL soil without amendment or amended with inorganic N (urea) or a combination of Biosolids (BS) and propriety microbial preparation namely BioVam® (BV). BS was applied at 30 or 45 g kg-1 soil and BV was kept constant at 10% (w/w). Results the experiment showed that the presence of MHM depressed total biomass productivity by 96% compared to controls. A combination of 30 g kg-1 BS with BV resulted in significant total biomass enhancement of 11.4 g TY pot-1, compared to other treatments. Analysis of plant tissues showed that As and to a lesser extent Cu accumulated preferentially in TY roots; Cr generally showed lower tendency to accumulate in TY tissue. Another pot experiment was conducted to ascertain, among other things, the independent role of BS or BV on responses of TY. Results from that experiment showed that amending with BV alone enhanced biomass production of 5.78 g pot-1 of TY compared to 1.84 g pot-1 for unamended MHM-fortified soils. Also, analysis of plant tissues in this experiment aligned with the first experiment as MHMs were generally restricted to below-ground biomass. Biochemical assays of oxidative stress biomarkers showed that levels of malondialdehyde (MDA), an indicator of lipid peroxidation was significantly lower in MHM-grown, BV-enhanced plant systems compared to plants grown in MHM-fortified soil only. The results strongly suggested that under appropriate soil inoculation strategies with BioVam (or similar microbial preparation), TY can be developed into an effective agent of phytoremediation agent for mitigating mixed heavy metal contamination in soil.

Subject Area

Sustainability|Biochemistry|Plant sciences|Soil sciences

Recommended Citation

Lynda Peter, "Mixed Metal Phytoremediation Potentials with Industrial Hemp Cannabis Sativa L" (2020). ETD Collection for Tennessee State University. Paper AAI28027368.