Combined application of rhizobacteria, organic and inorganic amendments reduce lead and cadmium uptake and improve growth of chickpea by modulating physiology and antioxidant status.

Abstract

Due to a lack of high-quality water, farmers have been compelled to use sewage water for irrigation, contaminating agricultural soils with multiple heavy metals. For the remediation of contaminated soil, plant growth-promoting rhizobacteria (PGPR), pressmud (PM), and iron (III) oxide were used to improve the growth and phytostabilization potential of chickpea grown in contaminated soil. Contaminated soil was collected from a nearby field, receiving sewage and factory water over the last 60 years. Chickpea seeds were inoculated with metal-tolerant (lead and cadmium) rhizobacterial and rhizobial strains. It was observed that combined application of rhizobia, rhizobacteria, iron oxide, and pressmud improved shoot fresh weight (87%), root fresh weight (47.9%), root length (47.9%), nodules plant^-1 (2.58 folds), photosynthetic rate (63%) and grain yield (39%) of chickpea as compared to respective untreated control in contaminated soil. Moreover, a significant decrease in the lead (75.8 and 68.1%) and cadmium (81 and 72%) concentrations due to the combined application of rhizobacteria, rhizobia, iron oxide, and pressmud was observed in shoot and root of chickpea than respective control, respectively. It can be concluded that the contaminated soil with mixed metals can be remediated, and the growth and yield of chickpea can be improved.