Phytoremediation efficiency of Vigna mungo with the amalgamation of indigenous metal tolerant bacterial strain on metal polluted agriculture soil

Abstract

This research was performed to evaluate physico-chemical properties of farmland soil nearby the magnesite mine site. Unexpectedly, few physico-chemical properties were crossing the acceptable limits. Particularly, the quantities of Cd (112.34 ± 3.25), Pb (386.42 ± 11.71), Zn (854.28 ± 3.53), and Mn (2538 ± 41.11) were crossing the permissible limits. Among 11 bacterial cultures isolated from the metal contaminated soil, 2 isolates names as SS1 and SS3 showed significant multi-metal tolerance up to the concentration of 750 mg L−1. Furthermore, these strains also showed considerable metal mobilization as well as absorption ability on metal contaminated soil under in-vitro conditions. In a short duration of treatment, these isolates effectively mobilize and absorb the metals from the polluted soil. The results obtained from the greenhouse investigation with Vigna mungo revealed that the among various treatment (T1 to T5) groups, the T3 (V. mungo + SS1+SS3) showed remarkable phytoremediation potential (Pb: 50.88, Mn: 152, Cd: 14.54, and Zn: 67.99 mg kg−1) on metal contaminated soil. Furthermore, these isolates influence the growth as well as biomass of V. mungo under greenhouse conditions on metal contaminated soil. These findings suggest that combining multi-metal tolerant bacterial isolates can improve the phytoextraction efficiency of V. mungo on metal-contaminated soil.