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Microorganism-related technologies are alternative and traditional methods of metal recovery or removal. We identified and described heavy metal-resistant bacteria isolated from polluted industrial soils collected from various sites at a depth of 0-200 mm. A total of 135 isolates were screened from polluted industrial soil. The three most abundant isolate strains resistant to heavy metals were selected: Paenibacillus jamilae DSM 13815T DSM (LA22), Bacillus subtilis ssp. spizizenii DSM 15029T DSM (MA3), and Pseudomonas aeruginosa A07_08_Pudu FLR (SN36). A test was conducted to evaluate the effect of (1) isolated heavy metal-resistant bacteria (soil application), (2) a foliar spray with silicon dioxide nanoparticles (Si-NPs), and (3) moringa leaf extract (MLE) on the production, antioxidant defense, and physio-biochemical characteristics of spinach grown on heavy metal-contaminated soil. Bacteria and MLE or Si-NPs have been applied in single or combined treatments. It was revealed that single or combined additions significantly increased plant height, shoot dry and fresh weight, leaf area, number of leaves in the plant, photosynthetic pigments content, total soluble sugars, free proline, membrane stability index, ascorbic acid, relative water content, a-tocopherol, glycine betaine, glutathione, and antioxidant enzyme activities (i.e., peroxidase, glutathione reductase, catalase, superoxide dismutase, and ascorbate peroxidase) compared with the control treatment. However, applying bacteria or foliar spray with MLE or Si-NPs significantly decreased the content of contaminants in plant leaves (e.g., Fe, Mn, Zn, Pb, Cd, Ni, and Cu), malondialdehyde, electrolyte leakage, superoxide radical (O·-2), and hydrogen peroxide (H2O2). Integrative additions had a more significant effect than single applications. It was suggested in our study that the integrative addition of B. subtilis and MLE as a soil application and as a foliar spray, respectively, is a critical approach to increasing spinach plant performance and reducing its contaminant content under contaminated soil conditions. [ABSTRACT FROM AUTHOR]

A pot experiment was carried out on lettuce (Lactuca sativa L.) for growing 2021 season to study the effect of various water sources i.e., fresh water (FW), agricultural drainage (ADW), sewage (SW) and industrial drainage (IDW) after treated with moringa seed extract (MSE) on remove water and soils contamination and its effect on yield and heavy metals content of lettuce plants. The lowest values of SSP, SAR, SCAR, RSC, RSBC, PI, PS, KR and MAR were obtaind in fresh water followed by industrial drainage water, sewage water and agricultural drainage water when treated with MSE. The classification of all water sources indicates before treated with MSE of high salinity-low sodicity (C4S1) and moderate low sodicity (C2S1) after treated with MSE. Addition of MSE to water soureces reduced water turbidity, NO3-N, BOD, COD, DO and heavy metals compared with untreated water. The highest values of fresh and dry weight, N, P and K- uptake of lettuce plants obtainted in different water sources treated with MSE. Addition of MSE to different water sources gave the lowest accumulation of Pb, Cd, Ni, Fe, Cu, Zn and Mn in soil and lettuce plants compared to untreated water. [ABSTRACT FROM AUTHOR]