RHIZOSTABILIZATION OF METALS IN SOILSUSING LUPINUS LUTEUSINOCULATED WITH THE METAL RESISTANT RHIZOBACTERIUMSERRATIASP. MSMC541

Abstract

The aim of this work was to test Lupinus luteus plants, inoculated with metal resistant rhizobacteria, in order to phytostabilise metals in contaminated soils. The resistance to heavy metals of strains isolated from nodules of Lupinus plants was evaluated. The strain MSMC541 showed multi-resistance to several metals (up to 13.3 mM As, 2.2 mM Cd, 2.3 mM Cu, 9 mM Pb and 30 mM Zn), and it was selected for further characterization. Furthermore, this strain was able to biosorb great amounts of metals in cell biomass. 16S rDNA sequencing positioned this strain within the genus Serratia. The presence of arsenic resistance genes was confirmed by southern blot and PCR amplification. A rhizoremediation pot experiment was conducted using Lupinus luteus grown on sand supplemented with heavy metals and inoculated with MSMC541. Plant growth parameters and metal accumulation were determined in inoculated vs. non-inoculated Lupinus luteus plants. The results showed that inoculation with MSMC541 improved the plant tolerance to metals. At the same time, metal translocation to the shoot was significantly reduced upon inoculation. These results suggest that Lupinus luteus plants, inoculated with the metal resistant strain Serratia sp. MSMC541, have a great potential for phytostabilization of metal contaminated soils.

Phytoremediation Using Algae and Macrophytes: I

“…The direct function of rhizosphere-associated algae is the alteration of metal concentration and/or accumulation within plant tissues, and indirectly they are involved in the increase in the root/shoot biomass. Similarly, fungi through antioxidant enzymatic activities alter the biochemical and physiological processes of plant tolerance to heavy metals (Rajkumar et al 2012 ;Yamane et al 2004 ;Jiang and Zhang 2002 ;Glick 2010 ;Aafi et al 2012 ;Miransari 2011 ;Ma et al 2011 ;Rajkumar et al 2010 ;Yang et al 2012 ;Wenzel 2009 ).…”

Scouting contaminated estuaries: Heavy metal resistant and plant growth promoting rhizobacteria in the native metal rhizoaccumulator Spartina maritima

“…When metal phytostabilisation was aimed, bacteria were able to promote plant growth and reduce either plant metal uptake or its translocation to the shoot, thus preventing the impact of metals in plant development and their entrance into the food chain. Thus, several works have reported that phytostabilisation of metal-polluted soils can be positively affected by the inoculation with PGPRs (Glick, 2010;Dary et al, 2010;El Aafi et al, 2012).…”

Dissolution of Arsenic Minerals Mediated by Dissimilatory Arsenate Reducing Bacteria: Estimation of the Physiological Potential for Arsenic Mobilization

“…and Serratia spp. strains were able to reduce arsenate, but only using cytoplasmic reductase as a resistance mechanism [20, 29, 30]. …”