Potential Phytoextraction with in-vitro regenerated plantlets of Brassica juncea (L.) Czern. in presence of CdCl$_2$: Cadmium accumulation and physiological parameter measurement

TL;DR

This study investigates the potential of in-vitro regenerated Brassica juncea plantlets for cadmium phytoremediation, showing they can accumulate cadmium with minimal impact on growth and physiological parameters, suggesting a promising remediation technology.

Contribution

It demonstrates that in-vitro regenerated B. juncea plantlets can accumulate cadmium effectively with low translocation to shoots, offering a novel approach for phytoremediation of contaminated soils.

Findings

Plantlets tolerate 75 μM CdCl₂ without growth reduction.

Roots accumulate the highest cadmium levels among plant parts.

In-vitro regeneration reduces cadmium translocation to shoots.

Abstract

Heavy metal contamination of agricultural land is partly responsible for limiting crop productivity. Cd$^{2+}$ is known as a non-essentiel HM that can be harmful to plants even at low concentrations. Brassica juncea (L.) is able to accumulate more than 400 $\mu$g.g$^{-1}$ D.W. in the shoot, a physiological trait which may be exploited for the phytoremediation of contaminated soils and waters. . The application of 75 $\mu$M CdCl$_2$ for three days does not show any effect in the B. juncea growth parameters (F.W. and D.W.) whatever the type of plantlets. This application decreases also the contents of chlorophyll a, carotenoids and Chl a/b ratio (2.26) for plantlets regenerated in the absence of CdCl$_2$ but not those of plantlets regenerated in its presence. Roots have the highest contents (3071; 1544 $\mu$g.g$^{-1}$ D.W.) followed by stems (850; 687$\mu$g.g$^{-1}$ D.W.) and leaves (463; 264$\mu$g.g$^{-1}$ D.W.) respectively. In our conditions, we suggest that the low accumulation in the plantlets regenerated in the presence of CdCl$_2$ by the means of in-vitro regeneration technology is still benefical, to some extent, for the phytoextraction process and seems to be an interesting technology that allows the cultivation of these plantlets in contaminated soils with low accumulation of metal in their shoots and probably in their seeds used in many food technologies.