Antagonistic effect of Trichoderma isolates and its metabolites against Fusarium solani and F. oxysporum in chickpea / Efeito antagonista de isolados de Trichoderma e seus metabólitos contra Fusarium solani e F. oxysporum em grão-de-bico

Abstract

The aim of this work was to study and select Trichoderma sp. strains with biocontrol potential against Fusarium solani and F. oxysporum, the causal agents of root rot and wilt in chickpea. Antagonism against pathogenic isolates of F. solani and F. oxysporum of twenty-one isolates of Trichoderma sp. obtained from the rhizosphere of chickpea plants were evaluated in vitro through competition in dual culture tests as well as the production of volatile and non-volatile organic compounds exhibiting fungicidal and/or fungistatic activity. In the in vivo experiment, four isolates of Trichoderma sp. were selected and their antagonism was evaluated separately and combined with a commercial product based on T. asperellum under greenhouse conditions. Trichoderma sp. isolates were efficient competitors and produced metabolites capable of inhibiting mycelial growth of both species of Fusarium. Our results show the great versatility of the mechanisms of action from Trichoderma isolates, mainly associated with the production of volatile organic compounds. Despite the antagonistic effect of Trichoderma isolates observed in vitro, these isolates did not control Fusarium neither promote chickpea growth in in vivo conditions.