Actinomicetos mineralizadores de fosfato involucrados en la interacción radical de Glomus sp. - trébol blanco.

Abstract

The objective of this work was to determine the capacity of actinomicetes for organic phosphorus mineralization and their rhyzospereinteraction with mycorrhiza of Trifolium repens L. (whiteclover). In January 2009, at the laboratory of the Unidad deInvestigaciones Agropecuarias (UNIDIA) of the Pontifi ciaUniversidad Javeriana, Bogotá, Colombia, the phosphataseactivity of Streptomyces sp. (strain MCR9), Streptomycessp. (strain MCR26) and Thermobifi da sp. (strain MCR24)were determined using the p-nitrofenil phosphate technique.Thermobifi da sp. (strain MCR24) showed the lowest activity.Inoculation of actinomycetes alone resulted in higher valuesof inorganic soil P, while leaf P content was higher when coinoculationof actinomycete-Glomus sp. occurred, with theexception of the strain Thermobifi da sp. (strain MCR24). Coinoculation with actynomicetes and Glomus sp. stimulatedbiomass production and colonization percent. Actynomicetesare sinergistic with Glomus sp., resulting in benefi ts for theplant and the mycorrhiza. Analysis of variance and “t” testsALS (P<0,05) were conducted to compare the treatments.The relation between the degree of mycorrhization plant dryweight was determined by the “r” correlation coeffi cient, andplants associated with microorganisms was higher than 70%.