Use of non-hyperaccumulator plant species for the phytoextraction of heavy metals using chelating agents

Abstract

Soil contamination by heavy metals is a challenge faced by many countries, and engineering technologies to solve this problem are expensive and can cause negative impacts on the environment. One way to minimise the levels of heavy metals in the soil is to use plants that can absorb and accumulate heavy metals into harvestable parts, a process called phytoextraction. Typical plant species used in research involving phytoextraction are heavy metal hyperaccumulators, but plants from this group are not good biomass producers and grow more slowly than most species; thus, they have an important role in helping scientists understand the mechanisms involved in accumulating high amounts of heavy metals without developing symptoms or dying. However, because of their slow growth, it is not practical to use these species for phytoextraction. An alternative approach is to use non-hyperaccumulator plants assisted by chelating agents, which may improve the ability of plants to accumulate more heavy metals than they would naturally. Chelating agents can be synthetic or organic acids, and the advantages and disadvantages of their use in improving the phytoextraction potential of non-hyperaccumulator plants are discussed in this article. We hope to draw attention to ways to improve the phytoextraction potential of non-hyperaccumulator plants that produce a large amount of biomass and to stimulate more research on phytoextraction-inducing substances.

Root avoidance of toxic metals requires the GeBP‐LIKE 4 transcription factor in Arabidopsis thaliana

“…Heavy metal hyperaccumulating plants, such as Noccaea caerulescens (formerly Thlaspi caerulescence), Noccaea praecox and Arabis paniculata, have received much attention as potential candidates for phytoextraction of heavy metals from contaminated soils. However, their slow growth and small biomass remain major obstacles for applications in phytoextraction (Meyer & Verbruggen, 2012;Souza et al, 2013). Therefore, using genetic engineering techniques to convert nonhyperaccumulators with large biomasses and rapid growth rates into hyperaccumulators presents an attractive strategy for cleaning up contaminated soils.…”

Honey from Stingless Bee as Indicator of Contamination with Metals

“…Possibly, there is some metal accumulator species among the identified pollen types of Fabaceae, as these metals can be absorbed by the plants and accumulated mainly in the roots and shoots (Vasconcelos et al, 2012). Barbosa et al (2017) and Souza et al (2013) cited some examples.…”

Assessment of Plants at Petroleum Contaminated Site for Phytoremediation

“…And in all of those studies, the plants tested were able to present a successful phytoremediations effects towards the contaminants. Some plants have been used as a phytoaccumulator of metals [8], at…”