Characterization of biomass sorghum for copper phytoremediation: photosynthetic response and possibility as a bioenergy feedstock from contaminated land
In order to decrease the concentration of toxic metals in contaminated lands, phytoextraction can be suitable considering the use of plant species with high potential for biomass production, such as biomass sorghum (Sorghum bicolor L.). We assessed a biomass sorghum (BRS716) potential as a copper phytoextractor as well as the physiological stability under this stressful condition. A completely randomized experimental design was used for a greenhouse experiment in which sorghum plants were submitted to a range of Cu2+ concentrations: 2.3, 10.9, 19.6, 30.5, 37.6 and 55.6 mg dm−3. The plant growth was not affected by increasing Cu2+ concentrations, suggesting that this species is tolerant to copper. There was a decrease in photosynthetic rate according to the increase in Cu2+ concentration, but not at a level that could disturb plant metabolism and eventual death. The values obtained for transfer index ranged from 0.62 to 0.11 which evidenced the restriction of Cu2+ transport to the aerial parts. The more Cu2+ available in soil, the smaller the amount of Cu2+ transported to aerial parts of sorghum. So, our results show that biomass sorghum has potential to be used for Cu2+ phytoextraction in concentration of up to 20 mg dm−3. Also, in heavily Cu2+ polluted sites, it can be used to produce biomass for bioenergy purpose, promoting a low rate of Cu2+ extraction.
KeywordsBioenergy Environmental protection Toxic metals Plant production Clean technology Photosynthesis
The authors acknowledge: Dr. Rafael Augusto Costa Parrella to kindly give biomass sorghum BRS-716 seeds; FAPESP for the following Grant (2015/09567-9); IF Goiano, FEIS-UNESP, FAPEG, CNPq and CAPES for general fundings to institutions.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- Broadley M, Brown P, Cakmak I, Rengel Z, Zhao F (2012) Function of nutrients: micronutrients. In: Maschner P (ed) Marschner’s mineral nutrition of higher plants, 4th ed. Academic PressGoogle Scholar
- Evangelou MWH, Papazoglou EG, Robinson BH, Schulin R (2015) Phytomanagement: phytoremediation and the production of biomass for economic revenue on contaminated land. In: Ansari AA, Gill SS, Gill R, Lanza GR, Newman L (eds) Phytoremediation: management of environmental contaminants. Springer, Switzerland, pp 115–132Google Scholar
- Panda P, Sahoo L, Panda SK (2015) Heavy metal and metalloid stress in plants: the genomics perspective. In: Chakraborty U, Chakraborty B (eds) Abiotic stresses in crop plants. CABIGoogle Scholar
- Rabêlo FHS, Borgo L, Lavres J (2018) The use of forage grasses for the phytoremediation of heavy metals: plant tolerance mechanisms, classifications, and new prospects. In: Matichenkov V (ed) Phytoremediation: methods, management and assessment. Nova Science Publishers, New York, pp 59–102Google Scholar
- Souza LA, Camargos LS, Carvalho MEA (2018) Toxic metal phytoremediation using high biomass non-hyperaccumulator crops: new possibilities for bioenergy resources. In: Matichenkov V (ed) Phytoremediation: methods, management and assessment. Nova Science Publishers, New York, pp 1–26Google Scholar
- Subramani T, Florence HR, Kavitha M (2014) Climate change energy and decentralized solid waste management. Int J Eng Res Appl 4:205–216Google Scholar