Fungal endophytes as biocontrol agents: identification of bioactive secondary metabolites.

DIMARI G; CECATI FM; RETA GF; KURINA SANZ M; MAGALLANES-NOGUERA C

Mendoza

Congreso; IV Reunión Conjunta de Sociedades de Biología de la República Argentina; 2020

sociedad de Biología de Cuyo (SBC)

The use of endophytes as biocontrol agents is a sustainable, affordable and, eco-friendly alternative to deal with plant diseases of high agricultural importance. The potential lies on the pathogen resistance that endophytes confer to the plant and the mutual benefits generated by the symbiotic association such as the increase in nutrients up-take, the growth promotion and, the higher stress tolerance. With the aim of discovering new biological control agents, the inhibitory activity of three endopthytic fungal strains isolated from the endemic plant Eupatorium buniifolium was assessed. The fungi were identified as Fusarium solani Eb01, Alternaria alternata Eb03 and, Neofusicocum sp. Eb04. Firstly, we tested the antagonistic effect of the three endophytic strains against each other and later we faced them toward a panel of well-known phytopathogens by confrontation experiments carried out on solid media. F. solani Eb01 not only inhibit the growth of the other two endophytic strains but also inhibit the mycelial development of Aspergillus flavus, A. niger, Sclerotinia sclerotiorum, Fusarium oxysporum and, Penicillium chrysogenum. Further, we addressed the identification of the F. solani metabolites potentially responsible for the antifungal activity. Therefore, the fungi was cultured in PDB liquid media and the organic extract was obtained. By Gas Chromatography and Mass spectrometry analysis (GC-MS) we detected two δ-lactones as major components, namely 5,6-dihydro-6-pentyl 2H-pyran-2-one or massoia lactone and tetrahydro-4-hydroxy-6-pentyl-2H-pyran-2-one. These results suggest that F. solani Eb01 and/or its metabolites are good candidates to propose biological control strategies for agriculture.