Heavy metal ions, such as Cd, Hg, Pb, and As, tend to persist in soil without natural degradation and can be absorbed by crops, leading to the accumulation of agricultural products that pose a significant threat to human health. However, the development of a rapid and efficient technique for identifying heavy metals in agricultural products is essential to ensure health and safety. With the knowledge of the extent of damage caused by heavy metals, it becomes imperative to detect the presence of cadmium in the soil, water, and the environment. This study introduces a novel plate approach for quick and precise colorimetric detection of cadmium ions using the Cd(II)-Chrome Azurol S CAS-2,2 '-dipyridyl dipy-Cetylpyridinium Bromide CPB quaternary complex. Our innovative method has shown that at a reaction solution pH of 11, the optimal concentration ratio is CAS (5 x 10-3 M): dipy (0.1 M): CPB (1.0 x 10-3 M) = 4 mL: 1 mL: 1 mL. The most significant fading alert was observed when the ethylenediaminetetraacetic acid (EDTA) chelator was added dropwise to the CAS detection plate, indicating strong chelation of Cd by EDTA. This laboratory-based study established a foundation for future applications in real environmental sample analysis.

Escalating anthropogenic activities have caused heavy metal contamination in the environmental matrices. Due to their recalcitrant and toxic nature, their occurrence in high titers in the environment can threaten survival of biotic components. To take the edge off, remediation of metal-contaminated sites by phytoremediators that exhibit a potential to withstand heavy metal stress and quench harmful metals is considered an eco-sustainable approach. Despite the enormous potential, phytoremediation technique suffers a setback owing to high metal concentrations, occurrence of multiple pollutants, low plant biomass, and soil physicochemical status that affect plants at cellular and molecular levels, inducing morphological, physiological, and genetic alterations. Nevertheless, augmentation of soil with microorganisms can alleviate the challenge. A positive nexus between microbes, particularly plant growth-promoting microorganisms (PGPMs), and phytoremediators can prevent phytotoxicity and augment phytoremediation by employing strategies such as production of secondary metabolites, solubilization of phosphate, and synthesis of 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase and phytohormones. Microbes can mediate tolerance in plants by fortifying their antioxidant machinery, which maintains redox homeostasis and alleviates metal-induced oxidative damage in the plants. Associated microbes can also activate stress-responsive genes in plants and abridge metal-induced toxic effects. An in-depth exploration of the mechanisms employed by plant-associated microbes to trigger tolerance in phytoremediators is crucial for improving their phytoremediation potential and real-world applications. The present article attempts to comprehensively review these mechanisms that eventually facilitate the development of improved/new technology for soil ecosystem restoration.

The increasing level of cadmium (Cd) contamination in soil due to anthropogenic actions is a significant problem. This problem not only harms the natural environment, but it also causes major harm to human health via the food chain. The use of chelating agent is a useful strategy to avoid heavy metal uptake and accumulation in plants. In this study, randomized design pot experiment was conducted to evaluate potential role of malic acid (MA) and tartaric acid (TA) foliar spray to mitigate Cd stress in Spinacia oleracea L plants. For Cd stress, S. oleracea plants were treated with CdCl2 solution (100 mu M). For control, plants were given distilled water. One week after Cd stress, MA and TA foliar spray was employed at concentration of 100 and 150 mu M for both. The results of this study revealed that Cd stress (100 mu M) significantly reduced growth attributes, photosynthetic pigments and related parameters and gas exchange attributes. Cadmium stress also stimulated antioxidant defense mechanism in S. oleracea. Cd stressed plants had elevated levels of Cd metal ions in root and consumable parts (i.e. leaves) and caused severe oxidative damages in the form of increased lipid peroxidation and electrolytic leakage. MA and TA supplements at both low and high levels (100 and 150 mu M) effectively reversed the devastating effects of Cd stress and improved growth, photosynthesis and defense related attributes of S. oleracea plants. These supplements also prevented excessive accumulation of Cd metal ions as indicated by lowered Cd metal contents in MA and TA treated plants. These findings demonstrated that MA and TA treatments can potentially reduce Cdl induced phytotoxicity in plants by reducing its uptake and enhancing photosynthesis and defense related parameters.