Lotus spp.: a promising tool for rhizoremediation in the Humid Pampa

MASSOT, F; MERINI, LJ; GIULIETTI, AM

Mendoza

Congreso; XLVIII Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2012

The Humid Pampa region is the main agricultural area in Argentina. Intensive agricultural activities practiced on these soils with agrochemicals application, affect soil microbiology and generate surface and groundwater pollution. Herbicides are one of the most used pesticides; among which glyphosate stands out. Rhizoremediation is a potential strategy to minimize its environmental impact. Our aim was to assess glyphosate tolerance of two Lotus genus accessions, for selecting them as candidates for rhizoremediation strategies. Tolerance assays were performed in maximum bioavailability Murashige-Skoog (MS) semisolid agar media at 5 glyphosate concentrations, corresponding to a standard agronomic dose (1Kg ha-1 of Ultramax Glyphosate) reaching different soil depths. The seeds were scarified, surface sterilized, and then sowed in groups of ten in MS media. The germination rate, seedlings survival, growth and general status were registered. All levels showed the same germination rate at the end of the assay, and plantlet growth was observed up to a level of 5 mg.Kg-1. Furthermore, there was no significant difference in seedling growth between control and levels of 0,5 and 1,0 mg.Kg-1. To our knowledge, there is no previous report of glyphosate tolerance in Lotus spp. and this is a first approach towards utilizing it in rhizoremediation strategies.