Impact of Green Manures in Mitigating Heavy Metal Toxicity: A Review

The contamination of soil with heavy metals poses a serious threat to both ecology and public health. Human activity, such as mining, excessive fertilizer application, and industrial processes, are among the various sources of heavy metal pollution. There are various green manure plant species used as potential for mitigating heavy metal toxicity, certain legume plants like Albizia leibbeck L., Bauhinia purpurea L., Dalbergia sissoo, Millettia peguensis Ali, and Pongamia pinnata are being looked for applications in phytoremediation. Various techniques such as bioremediation, phytoextraction, phytofiltration, phytovolatilization, rhizofiltration, phytodegradation, and phyto desalinization are employed to address environmental pollution. Phytoremediation, in particular, aims to collect pollutants from the environment and convert them into forms that can be easily extracted from plant tissues. Contamination by heavy metals is a severe environmental matter. However, there are various contemporary methods that offer potential solutions to address this issue. One such approach involves the use of biochar to decrease the bioavailability of heavy metals in soil. By binding to them reducing their availability for plant absorption and entry into the food chain. Genetic engineering permits researchers to insert genes into plants that improve their acceptance of heavy metals or increase their ability to accumulate them (phytoextraction). Consequently, the utilization of these conventional methods in phytoremediation has demonstrated the most favourable and sustainable outcomes, ensuring an eco-friendly approach for the ecosystem.