Growth, nutrient uptake and symbiosis with rhizobia and arbuscular mycorrhizal fungi in Lotus tenuis plants fertilized with different phosphate sources and inoculated with the phosphate-solubilizing bacterium Pantoea eucalypti M91

CASTAGNO L.N.; GARCÍA I.V.; SANNAZZARO A.I.; BAILLERES M. A.; RUIZ O.A.; MENDOZA R.E.; ESTRELLA M.J.

PLANT AND SOIL

SPRINGER

Lugar: Berlin; Año: 2014 vol. 385 p. 357 - 371

0032-079X

Background and Aims: The aim of this work was to evaluate the ability of P fertilization and phosphate-solubilizing bacteria (PSB) inoculation to promote the growth of L. tenuis in typical soils of the Salado River Basin (Argentina) with low P availability. Methods: Aboveground biomass and P and N levels were evaluated in field-grown L. tenuis plants inoculated with Pantoea eucalypti M91, either without fertilization or in combination with phosphate rock and triple superphosphate (TSP). The impact of P fertilization and inoculation on the symbiotic interactions between L. tenuis and native rhizobia bacteria and arbuscular mycorrhizal fungi was also evaluated.  Results:  Inoculation with M91 increased the L. tenuis biomass production and P concentration in shoots, at an early stage of plant growth. The combined treatment of inoculation with M91 and TSP significantly increased the P and N content in shoots compared to non-inoculated plants, fertilized or not.  P. eucalypti M91 was found to endophytically colonize roots and leaves of L. tenuis plants grown in vitro and also under field conditions. Conclusions: The results suggesting that inoculation of L. tenuis with the PSB such as P. eucalypti M91 strain might allow more efficient use of N and  P and a more sustainable option for  grasslands producers from the Salado River Basin, in order to reduce costs and avoid increased levels of P insoluble in soils.