Hyperaccumulator Plants for Soil Remediation, Crop Protection, and Phytomining: An Integrated Sustainable Approach / Review Article

Sama Hassan Ali Rahmatullah; Muna Mohammed Khayri; Ali Mahdi Salih; Diyar Abdullah Najm

Authors

Sama Hassan Ali Rahmatullah University of Baghdad/College of science/Department of Biotechnology
Muna Mohammed Khayri University of Baghdad/College of science/Department of Biotechnology
Ali Mahdi Salih Tropical biological research unit ,college of science, University of Baghdad, Baghdad, Iraq
Diyar Abdullah Najm Tropical biological research unit ,college of science, University of Baghdad, Baghdad, Iraq

Keywords:

Phytoremediation, superaccumulating plants, heavy metal pollution, biotrape crops, phytomining

Abstract

Heavy metal contamination of agricultural soil is one of the most serious environmental challenges. Traditional physical and chemical remediation methods are not only costly but also environmentally damaging and unsuitable for large-scale farming. Phytoremediation, particularly the use of superaccumulating plants, represents a novel and environmentally friendly approach to soil treatment. These plants possess a unique ability to accumulate metals at concentrations hundreds or thousands of times higher than ordinary plants, utilizing a range of advanced physiological and molecular techniques. The novel concept of using these plants as biological traps has paved the way for the preventative protection of food crops from contamination. By employing a combination of phytomining, nanotechnology, and plant-root-stimulating bacteria, the remediation capacity of these plants has been further enhanced, making this method economically viable. This paper explores the use of superaccumulating plants in soil remediation and food security protection, proposing a new and advanced framework for environmentally friendly remediation and protection. The Problem Statement: Heavy metals, such as lead, cadmium, mercury, nickel, and arsenic, accumulate in agricultural soils as a result of industrial, mining, and agricultural activities. The long-term degradation of heavy metals is attributed to their chemical stability, such as their translocation to edible plant parts. This leads to foodborne exposure risks, particularly chronic health risks to humans, such as neurotoxicity, kidney disease, and cancer. It also contributes to ecosystem degradation, including reduced microbial populations and loss of fertility. Traditional methods for treating heavy metals in agricultural soils are costly, polluting, and less sustainable, highlighting the need for new, environmentally friendly approaches. Objectives of the Article: This article aims to explore the physiological and molecular basis of how heavy metals accumulate in superaccumulators and detoxify. It also evaluates the use of superaccumulators as attractive crops to prevent the translocation of heavy metals to food crops. Furthermore, it explores the use of superaccumulators in conjunction with phytomining and biotechnology techniques to improve the sustainability of soil treatment and increase economic benefits. Finally, it highlights the research challenges and limitations in using superaccumulators for treating heavy metals in agricultural soils. Methodology: This article was conducted using peer-reviewed publications that included experimental, field, and modeling studies. It focused on super-accumulating plant species, their molecular and physiological adaptations, and their applications in soil remediation, food crop protection, and mineral extraction. Phytoremediation mechanisms include phytoremediation, phytoremediation, phytostabilization, root leaching, and phytodecomposition, as well as integrated approaches to biotrape bioculture, phytomining, microbial activation, the use of nanoparticles, and predictive modeling. Superaccumulating plant species are characterized by their ability to accumulate heavy metals at extremely high concentrations without causing phytotoxicity, making them effective biofilters. Biotrape bioculture systems strategically place superaccumulating plant species to intercept metals, reducing the amount of metals transferred to food crops. Phytomining has the potential to transform harvested plant biomass into a valuable commodity, providing a strong incentive in addition to environmental benefits. However, several challenges hinder the effective and efficient implementation of phytoremediation, including low treatment rates, variability in pollutant accumulation due to environmental factors, and the management of contaminated biomass.

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