Role of PGPR for Cadmium Stress Alleviation

Heavy metal cadmium (Cd) is carcinogenic and harmful to ecosystems, microorganisms, and plants. The possibility of cadmium entering the food chain poses health risks to people all around the world. Cadmium enters plants through their roots from polluted soil and accumulates in edible sections. The effects of cadmium toxicity on plants’ physio-biochemical processes not only include the reduction in plant biomass, seed germination, and early seedling growth but also lead to chlorosis, necrosis, and obstruction of photosynthetic mechanisms. Additionally, plants are disrupted at the molecular level by reactive oxygen species (ROS), which subsequently damage DNA and cause gene mutation. When it comes to soil remediation contaminated with cadmium, phytoremediation is helpful, but its efficacy decreases as toxicity rises. Higher toxicity does not function with even hyperaccumulator plants. By accumulating or transforming pollutants, plant growth-promoting rhizobacteria (PGPR) offer a potential utility for soil bioremediation. The PGPR-assisted phytoremediation of cadmium-contaminated soils is highlighted in this chapter.