Inoculation of Indigenous Arbuscular Mycorrhizal Fungi as a Strategy for the Recovery of Long-Term Heavy Metal-Contaminated Soils in a Mine-Spill Area.

Symbiotic associations with arbuscular mycorrhizal fungi (AMF) offer an effective indirect mechanism to reduce heavy metal (HM) stress; however, it is still not clear which AMF species are more efficient as bioremediating agents. We selected different species of AMF: (Custos); sp. (Aznalcollar); and (Intraradices), in order to study their inoculation in wheat grown in two soils contaminated with two levels of HMs; we tested the phytoprotection potential of the different AMF symbioses, as well as the physiological responses of the plants to HM stress.

Rhizoremediation of lindane by root-colonizing Sphingomonas.

We used a two-step enrichment approach to isolate root-colonizing hexachlorocyclohexane (HCH)-degrading microorganisms. The first step consists of the use of classical liquid enrichment to isolate γ-HCH degraders. The γ-HCH-degrading microbes were attached in mass to corn seeds sown in soil with γ-HCH, and after plant development we rescued bacteria growing on root tips.

16S rDNA phylogeny and distribution of lin genes in novel hexachlorocyclohexane-degrading Sphingomonas strains.

Hexachlorocyclohexane (HCH) is a highly recalcitrant pesticide that persists in soils. Three novel HCH-degrading strains (DS2, DS2-2 and DS3-1) were isolated after enrichment from HCH-contaminated soil from Germany. These strains efficiently degraded the alpha-, gamma- and delta-isomers of HCH, while strain DS3-1 also degraded beta-HCH.