Evaluación in vitro del potencial antagonista de Trichoderma sp. y hongos endófitos de mora (Rubus glaucus Benth) para el control de Botrytis cinerea

Abstract

espanolUno de los principales problemas fitosanitarios en los cultivos de mora(Rubus glaucusBenth)del Ecuador es el hongo Botrytis cinerea causante de la enfermedad del “moho gris”. El objetivo de este estudio fue determinar la capacidad antagonica de cuatro hongos frente al patogenoB.cinerea. Para llevar a cabo esta investigacion se aislaron dos microorganismos endofitos del cultivo de mora(Clonostachyssp.y Alternariasp.)y se utilizaron aislados de TrichodermaasperellumyTrichoderma sp. de la coleccion de INIAP.Se utilizola tecnica de cultivos duales. Se utilizo la escala de Bell para evaluar el antagonismoy se calculo el porcentaje de inhibicion del crecimiento micelial parael efecto antagonico. T. asperellum yTrichoderma sp.alcanzaron el grado I en la escala de Bell, donde el antagonista inhibioel crecimiento de B. cinereaen un 75.1%y 73.7% respectivamente; mientras que el aislado de Clonostachyssp.alcanzo el grado II yse observoque sus esporas parasitaron los esclerocios de B. cinerea.Por otro lado,el asiladode Alternariasp. se ubicoen grado III,lo cual no se considero eficiente para inhibir el crecimiento del hongo patogeno EnglishOne of the main phytosanitary problems in blackberry (Rubus glaucusBenth) crops in Ecuador is the fungus Botrytis cinereathat causes gray mold disease. The objective of this study was to determine the antagonistic capacity of four fungi against the pathogen B.cinerea. To carry out this research,two endophytic blackberry microorganisms were isolated (Clonostachyssp.and Alternariasp.)and strains of Trichodermaasperellumand Trichodermasp. belonging to the INIAP s collection were used. The dual culture techniquewas used. The Bell scale was used to assess antagonism and the percentage of inhibition of mycelial growth was calculated for the antagonistic effect. T. asperellum yTrichoderma sp. grade I on the Bell scale, where the antagonist fungus inhibited the growth of B.cinereaby 75.1% and 73.7% respectively; while the isolateof Clonostachyssp. obtained grade II and despite its slow growth,it was observed that its spores parasitize the sclerotia of B. cinerea. On the other hand, the isolateof Alternariasp. was located in grade III, consequently it was not efficient to avoidthegrowth of thepathogenic fungus.