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through the process of phytodegradation or phytotransformation. Hyperaccumulators plants have
the highest metal accumulation ability but little biomass efficiency, whereas non-hyperaccumulators
plants have high biomass efficacy and lesser accumulation potential (Ojuederie and Babalola 2017).
Rhizofiltration is one of the techniques used to clean up different metal-contaminated water
resources through the precipitation of metals in the plant roots (Zulfiqar et al. 2019). Numerous
plant cultivars like Nicotiana tabaccum, Zea mays, Brassica juncea, Helianthus annus, and
Spinacia oleracea have been studied to clean Pb from the terrestrial and aquatic systems (Camargo
et al. 2003). Phytostabilization is another in-situ plant-mediated remediation of metals via inhibiting
their mobility and bioavailability (Kunito et al. 2001, Ali et al. 2013). Miscanthus floridulus showed
greater phytoremediation potential for Pb metal (Cheng et al. 2016). Co-plantation of Pteris vittata
and the Ricinus communis exhibited significant phytoextraction potential for the remediation of Pb
from the soil through an elevation in the yield of P. vittata after Pb uptake (Yang et al. 2017).
Pb content was observed to decline from 218 to 32 mg kg–1 in stem and 7232 to 1196 mg kg–1
in Lolium italicum and Festuca arundinaceae roots system, respectively due to the presence of
compost (Kushwaha et al. 2018). Ludwigia stolonifera exhibited significant efficiency of 99% for
the removal of Pb (Saleh et al. 2019). Cyamopsis tetragonoloba and Sesamum indicum showed
significant Pb phytoremediation potential with higher Pb accumulation in the root. It was further
reported that these plant cultivars can be grown on marginally contaminated soils and could be
practised for phytostabilization (Amin et al. 2018). Glycine max exhibited good potential for Pb
removal from the soil, and the content of organic carbon of soil was also reduced in the remediated
soil (Aransiola et al. 2013). Biochar prepared from rice husk and pinewood showed remarkable
ability to remove the Pb through the process of adsorption (Liu and Zhang 2009, Raj and Maiti
2020). Alyssum maritimum showed good phytoremediation potential by accumulating Pb in various
plant organs, with the highest in the leaf followed by the root and stem. It has also been suggested
that this plant can be involved in the family of hyperaccumulator plants, with a high potential for
remediating Pb from soil (Solgi et al. 2020). Athyrium wardii was reported to show significant Pb
phytostabilization ability via accumulating most of the Pb in roots (Zhao et al. 2016). Salix purpurea
exhibited higher phytostabilization as compared to Salix viminalis; however, both the species were
shown to develop lengthy roots under Pb stress (Sylvain et al. 2016). Overall, Pb content in different
essential food crops should be evaluated cautiously to mitigate the Pb triggered health impacts.
Various plant species that can be practised for Pb phytoremediation are presented in Table 11.1.
11.4.3 Algae and Fungi Assisted Remediation of Pb
Plant-associated algae and fungi play an important function in the remediation of Pb from the soil
by promoting the Pb accumulation in plants and plant growth in contaminated soil. Recent studies
reported that plant endophytes enhance their phytoremediation potential (Waranusantigul et al.
2011, Deng et al. 2011, Gupta et al. 2013). A study on Arbuscular Mycorrhizal (AM) fungi viz.
Glomus deserticola by Arias et al. (2010) revealed its Pb accumulation potential in Prosopis sp.
(mesquite plants). The Transmission Electron Microscopy (TEM) revealed G. deserticola’s
presence within the roots of Prosopis sp., which improved metal tolerance and accumulation in
plants. AM fungi reduce the Pb toxicity by inducing its accumulation in the plant’s roots, stems and
leaves. Further, phytoremediated Pb was found to be accumulated in the xylem and phloem cells of
mesquite plants. Another fungal endophyte, Mucor sp., CBRF59 helps in the remediation of Pb from
contaminated soil that has been recovered from rape roots growing in a heavy metal contaminated
environment. Inoculation of plant roots with mycelia of Mucor sp., CBRF59 significantly enhanced
the Pb availability of soil by 77% from contaminated soils (Deng et al. 2011). AM fungi are also
observed to reduce oxidative stress and improve plants growth in heavy metal contaminated sites.
Glomus mosseae inoculated Vetiver grass has increased chlorophyll content and decreased levels of
GSH, thereby increasing its ability to withstand metal-induced stress better. G. mosseae enhanced
the accumulation and translocation of Pb in Vetiver grass shoots (Punamiya et al. 2010).