Phytoremediation, Bioaugmentation, and the Plant Microbiome

Abstract

Understanding plant biology and related microbial ecology as a means to phytoremediate soil and groundwater contamination has broadened and advanced the field of environmental engineering and science over the past 30 years. Using plants to transform and degrade xenobiotic organic pollutants delivers new methods for environmental restoration. Manipulations of the plant microbiome through bioaugmentation, endophytes, adding various growth factors, genetic modification, and/or selecting the microbial community via insertion of probiotics or phages for gene transfer are future areas of research to further expand this green, cost-effective, aesthetically pleasing technology�phytoremediation.

Molybdenum Trioxide Nanoparticles as Promising Stimulators for Facilitating Phytoremediation by Cd Hyperaccumulator Solanum nigrum L

“…The detoxification mechanisms of hyperaccumulator species toward heavy metals are diverse, including cell-wall precipitation, metal chelation, antioxidative defense activation, and vacuolar compartmentalization. , As a typical Cd hyperaccumulator, S. nigrum has been reported to reveal regulations on cell-wall components, subcellular distribution, antioxidative levels, and metabolic pathways in response to Cd stress. , Dai et al further identified significantly regulated plasma membrane ATPase (ATP = adenosine triphosphate) activities in response to Cd pressure, which played important roles in membrane permeability for Cd penetration, while most hyperaccumulators revealed tolerance to a single metal type, which largely restrained the plant development of hyperaccumulators and phytoremediation efficiencies in actual contaminated sites . So far, the nanomaterials used to facilitate phytoremediation of heavy metals have been mainly carbon-based materials, followed by Fe-based materials, TiO 2 nanomaterials, and nanosilica, and several mechanisms related to stimulation in the plant performance and phytoremediation efficiency by nanomaterial application were considered. , For instance, Gong et al demonstrated that soil addition of 100 mg kg –1 starch-stabilized nano zerovalent iron (nZVI) promoted plant performances and Cd accumulation of Boehmeria nivea L. Gaudich by stimulating antioxidative defense systems and Cd penetration into cell walls.…”

Rice Seedlings and Microorganisms Mediate Biotransformation of Se in CdSe/ZnS Quantum Dots to Volatile Alkyl Selenides

“…Abundant endophytic and epiphytic plant-associated microorganisms live inside the plants and on the surface of plants. − Therefore, the hydroponic solution for seedling cultivation and exposure inevitably includes not only root exudates secreted from plants but also various microorganisms. Owing to the detection of alkyl selenides in the hydroponic solution of the QD-exposed seedling group, the specific contributions of the root exudates and plant-associated microorganisms to the transformation of CdSe/ZnS-GSH to alkyl selenides were explored.…”

“…The hydroponic solutions in our seedlings’ exposure experiments inevitably contain microorganisms because the seedlings were not bleached before use and the plant-associated microorganisms are ubiquitous. − Moreover, plants secret exudates containing soluble organic substances to the root zone . To investigate the biotransformation potential of root exudates and microorganisms in the hydroponic solution on CdSe/ZnS-GSH in the QD-exposed seedling group, pristine hydroponic solution, sterilized hydroponic solution, and sterilized ultrapure water were separately incubated with CdSe/ZnS-GSH QDs, as shown in Figure S3.…”

Arsenic-Hyperaccumulator Pteris vittata Effectively Uses Sparingly-Soluble Phosphate Rock: Rhizosphere Solubilization, Nutrient Improvement, and Arsenic Accumulation

“…While arsenate (AsV) is the dominant form under aerobic conditions, arsenite (AsIII) is mainly present under anoxic conditions like wetland and paddy soil . Being cost-effective and environmentally-friendly, plant-based phytoremediation technology has a potential to remediate As-contaminated soils …”

“…4 Being cost-effective and environmentally-friendly, plant-based phytoremediation technology has a potential to remediate As-contaminated soils. 5 Being the first-known As-hyperaccumulator, Pteris vittata can accumulate up to 23,000 mg kg −1 As in its fronds. 6 High As accumulation in plants typically induces their oxidative damage including P. vittata, with their cytotoxicity often being indicated by malondialdehyde (MDA) production.…”