Influence ofPseudomonas japonicaand organic amendments on the growth and metal tolerance ofCelosia argenteaL.

In this study, a pot experiment was piloted in a greenhouse to evaluate the potential ofCelosia argenteavar.cristataL. for tolerating/accumulating heavy metals in synthetic wastewater in the presence ofPseudomonas japonicaand organic amendment, i.e., moss and compost. Two-week-old seedlings were transferred to pots, and after 4 weeks, the bacterial strain was inoculated, then watered with synthetic wastewater for 5 weeks and harvested after 9 weeks. After harvesting, physiological and biochemical parameters, as well as metal contents of plants, were quantified. The results indicated highest growth and biomass production in moss- and compost-associated plants while highest metal uptake has been found in the presence ofP. japonicaand synthetic wastewater-irrigated plants. Synthetic wastewater-irrigated plants have shown highest Pb uptake of 2899 mg kg(-1)DW, while withP. japonicain soil those plants have shown highest Cd, Cu, Ni, and Cr uptake of 962, 1479, 1042, and 956 mg kg(-1)DW, respectively. The production of antioxidant enzymes, i.e., catalase (CAT), ascorbate peroxidase (APX), guaiacol peroxidase (GPX), and glutathione-s-transferase (GST), was high inP. japonica-amended plants because of increased uptake of metals. It is concluded that moss and compost have improved growth whileP. japonicaimproved metal accumulation and translocation to aerial parts with little involvement in plant growth.