title: Plant tolerance to mercury in a contaminated soil is enhanced by the combined effects of humic matter addition and inoculation with arbuscular mycorrhizal fungi.
abstract: In a greenhouse pot experiment, lettuce plants (Lactuca sativa L.) were grown in a Hg-contaminated sandy soil with and without inoculation with arbuscular mycorrhizal fungi (AMF) (a commercial inoculum containing infective propagules of Rhizophagus irregularis and Funneliformis mosseae) amended with different rates of a humic acid (0, 1, and 2 g kg(-1) of soil), with the objective of verifying the synergistic effects of the two soil treatments on the Hg tolerance of lettuce plants. Our results indicated that the plant biomass was significantly increased by the combined effect of AMF and humic acid treatments. Addition of humic matter to soil boosted the AMF effect on improving the nutritional plant status, enhancing the pigment content in plant leaves, and inhibiting both Hg uptake and Hg translocation from the roots to the shoots. This was attributed not only to the Hg immobilization by stable complexes with HA and with extraradical mycorrhizal mycelium in soil and root surfaces but also to an improved mineral nutrition promoted by AMF. This work indicates that the combined use of AMF and humic acids may become a useful practice in Hg-contaminated soils to reduce Hg toxicity to crops.
authors.affiliation: Centro Interdipartimentale di Ricerca sulla Risonanza Magnetica Nucleare per l'Ambiente, l'Agroalimentare ed i Nuovi Materiali (CERMANU), Università di Napoli Federico II, Via Università 100, Portici, 80055, Italy. cozzolino.vincenza@libero.it.
authors.forename: V
authors.initials: V
authors.lastname: Cozzolino
authors.affiliation: Dipartimento di Agraria, Università di Napoli Federico II, Via Università 100, Portici, 80055, Italy. ademarti@unina.it.
authors.forename: A
authors.initials: A
authors.lastname: De Martino
authors.affiliation: Centro Interdipartimentale di Ricerca sulla Risonanza Magnetica Nucleare per l'Ambiente, l'Agroalimentare ed i Nuovi Materiali (CERMANU), Università di Napoli Federico II, Via Università 100, Portici, 80055, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Nebbioso
authors.affiliation: Dipartimento di Agraria, Università di Napoli Federico II, Via Università 100, Portici, 80055, Italy.
authors.forename: V
authors.initials: V
authors.lastname: Di Meo
authors.affiliation: ENEA, Italian National Agency for New Technologies, Energy and the Environment, Centre of Research of Portici, Naples, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Salluzzo
authors.affiliation: Centro Interdipartimentale di Ricerca sulla Risonanza Magnetica Nucleare per l'Ambiente, l'Agroalimentare ed i Nuovi Materiali (CERMANU), Università di Napoli Federico II, Via Università 100, Portici, 80055, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Piccolo
mesh_terms: D018533:Biomass; D055137:Glomeromycota / Q000254:growth & development*; D006812:Humic Substances / Q000032:analysis* / Q000382:microbiology; D018545:Lactuca / Q000254:growth & development* / Q000378:metabolism / Q000382:microbiology; D008628:Mercury / Q000032:analysis / Q000378:metabolism / Q000633:toxicity*; D038821:Mycorrhizae / Q000254:growth & development*; D018517:Plant Roots / Q000254:growth & development / Q000378:metabolism / Q000382:microbiology; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism / Q000633:toxicity*
chemical_list: D006812:Humic Substances; D012987:Soil; D012989:Soil Pollutants; D008628:Mercury
keywords: Humic acid; Lettuce; Mercury; Metal toxicity; Natural organic matter; Phytostabilization; Plant uptake; Soil contamination