Phytoremediation: recent advances in plant-endophytic synergistic interactions

Abstract

Background Plant-endophyte partnership provides an excellent gateway toward restoration of contaminated ecosystems. The interactions between both partners can be manipulated by introducing novel catabolic/ metabolic genes into host plant or endophytic bacteria genomes. The potential of the engineered organisms to degrade or accumulate contaminants is much wider than their wild relatives. Scope This review covers the recent developments for engineering catabolic/metabolic genes from a wide range of sources into plants or endophytic bacteria for the development of modified plant-endophyte interactions. Genetic alteration of plants promises enhanced catabolism by plant's own enzymatic machinery or greater contaminant uptake/accumulation for subsequent in planta detoxification by complementary endophytes. On the other hand, bacteria may also be engineered to enhance the potential for degradation or alteration of catabolic pathways, either to protect the host plant against phytotoxicity or to improve the overall efficiency of phytoremediation in planta, a situation especially suitable when hydrophilic compounds fail to be degraded by rhizospheric microbes due to the rapid uptake by plants. This is followed by discussion on kinetic parameters controlling phytoremediation. Conclusions It is hypothesized that transgenic approach can result in synergistic and effective plant-endophyte partnerships for wider-range and enhanced capabilities of degrading and/or detoxifying contaminants.

The Oxidative Stress Response of Mirabilis jalapa to Exhausted Engine Oil (EEO) during Phytoremediation

“…The finding is further confirmed with enzymatic assays indicating the presence of high reactive oxygen species. Finally, the study confirms the toxic nature of EEO, and the results reflect that the plant is least suitable for phytoremediation of EEO but, in future, may be considered with improved phytotechnologies, i.e., a plant-bacteria partnership (rhizobacteria and endophytic bacteria) [12,39,52].…”

Editorial special issue: soil, plants and endophytes

“…However, more research is still needed to understand and improve increase phytoremediation processes. Related to this, Ijaz et al (2016) covered recent developments either on engineering catabolic/metabolic genes from a wide range of sources into plants or endophytic bacteria for the development of modified plant-endophyte interactions aiming to increase the effectiveness of phytoremediation strategies.…”

Restoration of degraded lands through bioenergy plantations

“…Many crop plants have the ability to remove soil contaminants with different modes of phytoremediation like phytoextraction, phytostabilization, phytovolatilization, phyto‐transformation, and rhizo‐filtration (Ijaz et al ). To accelerate these processes for land restoration many crop plants have been engineered using microbial or plant transgene in the last few decades.…”