Enhancing metal solubility and phytoextraction in soil under Indian mustard

Abstract

In phyto-extraction slow removal rate of metals by plant is the main constraint in the way of making effective use of this
green technique in managing contaminated site. Hence, an attempt has been made to study the effect of selected organic
and inorganic amendments on enhancing efficacy of phytoextraction of Zn, Cd and Pb in contaminated soil using Indian
mustard (Brassica juncea cv. Pusa Vijay) as a test crop. Results indicated that Cd availability in soil was increased from
38.7 to 96.7% under different amendments, whereas Pb availability enhanced from 53.8 to 94.0%. All the amendments
enhanced the EDTA and DTPA-extractable Zn, Cd and Pb in soil. Cadmium removal by shoot of mustard was enhanced
to the extent of 125, 62.5, 175, 175 and 212% under green manure, EDTA, S+S oxidizing bacteria, metal solubilizing
bacteria and green manure + metal solubilizing bacteria treated soil, respectively over control. Root parameters (i.e. root
length, diameter, surface area) also improved under different amendments. Application of green manure and metal
solubilizing bacteria was the most efficient in enhancing the Zn, Cd and Pb removal by Indian mustard and phytoextraction
from practical point of view.