Phytoextraction of heavy metals by two Salicaceae clones in symbiosis with arbuscular mycorrhizal fungi during the second year of a field trial

Abstract

We evaluated the potential of Salix viminalis (5027) and Populus × generosa for the phytoextraction of heavy metals (HM) inoculated or not with an arbuscular mycorrhizal (AM) fungus Glomus intraradices during a second year of growth in a randomized complete block field trial on a slightly contaminated site. Both plant clones produced high aboveground biomass yields, however P. × generosa produced significantly more biomass than S. viminalis. The two plant clones accumulated high concentrations of Cd and Zn in their shoots, while Cu and Pb were stored in their roots. In general, S. viminalis accumulated higher concentrations of HM. The inoculation of G. intraradices in the previous year did not influence plant clones' biomass yields during the second growing season. However, Cu and Cd translocation to shoots was limited, and Cu was preferentially concentrated in roots of inoculated plants, compared to non-inoculated plants, which were also colonized by native AM fungi taxa. Efficiency of S. viminalis and P. × generosa for Cd and Zn rehabilitation in slightly contaminated soil has been demonstrated, but mycorrhizal inoculation did not significantly increase HM extraction.

Effect of mycorrhizal inoculation on metal accumulation by poplar leaves at phytomanaged sites

“…In fact, specific root exudates released by trees trigger the expression of mycorrhization genes, resulting in symbiotic relationships between plants and mycorrhizal fungi (Churchland and Grayston, 2014 (Baum et al, 2002;Cicatelli et al, 2014;Mrnka et al, 2012) but rarely in field conditions. On a slightly contaminated site, Bissonnette et al (2010) reported that arbuscular mycorrhizal fungi inoculation had no significant effect on Cd accumulation in poplars shoots used for phytoextraction,. In most of the less contaminated areas of our study, PTE concentrations of poplar leaves did not vary under inoculation.…”

Influence of Soil Chemistry and Plant Physiology in the Phytoremediation of Cu, Mn, and Zn

“…AMF are ubiquitous terrestrial symbionts involving functioning parts of plants living in mutualistic association with the fungi (Meier et al, 2012). Symbiotic mycorrhizal associations can increase the efficiency of phytoremediation due to improvements in the uptake and delivery of nutrients to the plant and in tolerance to metal toxicity (Bissonnette et al, 2010;Cornejo et al, 2013;Hernandez-Ortega et al, 2012). For example, the nonpathogenic Fusarium fungus was able to increase S. alfredii root system function, metal availability and accumulation, plant biomass, and thus Zn phytoextraction efficiency (Zhang et al, 2012a).…”

Influence of mycorrhizal inoculation on growth of micropropagated Populus × canescens lines in metal-contaminated soils

“…Both, ectomycorrhizal (ECM) and arbuscular mycorrhizal (AM) associations may play an important role in establishment of vegetation in highly polluted soils (Turnau et al 2006). The ability to accumulate and detoxify heavy metals show ECM fungi (Turnau et al 1996;Rudawska and Leski 2005;Ott et al 2002;Luo et al 2014;Ma et al 2014) and AM fungi (Joner et al 2000;Hildebrandt et al 2007;Bissonnette et al 2010;Bothe et al 2010;Cicatelli et al 2014). Mycorrhizal fungi can also enhance the host plant tolerance by influence on its defence genes ).…”