Evaluación de la capacidad antagónica in vitro de dos cepas de Trichoderma sp. frente a hongos fitopatógenos aislados desde árboles de Schizolobium parahybum (Vell.) S.F. Blake (pachaco) con síntomas de la enfermedad “decaimiento y muerte descendente” en el Trópico Húmedo Ecuatoriano

The purpose of this research was to evaluate new alternatives such as biological control, using the antagonism of Trichoderma sp., for the control of S. parahybum diseases at the in vitro level. The in vitro antagonistic capacity of two native strains of Trichoderma sp. against S. parahybum phytopathogens, as well as its effect at three different temperatures and its growth rate. Dual cultures were performed in potato-dextrose-agar (PDA) culture medium, incubated at three temperatures (4 ± 2 ° C, 24 ± 2 ° C and 30 ± 2 ° C) under a completely randomized design, with 9 treatments, constituted by the combination of the three phytopathogens (Fusarium sp. 1, Fusarium sp. 2 and Botryodiplodia sp.) and two strains of Trichoderma sp. For each treatment, five repetitions (Petri dishes) were used. The antagonistic capacity was determined by estimating the percentage of radial growth inhibition (PICR) of the phytopathogens in the presence of Trichoderma sp. every 24 hours, until 168 hours of incubation under the three temperature conditions. The antagonistic capacity was evaluated using a scale of 5 categories. The temperature variation did influence the growth of two strains of Trichoderma sp. showed adaptability at temperatures of 24±2 ° C and 30±2 °, with rapid development between 48 and 72 hours after incubation. Trichoderma sp.2 showed greater aggressiveness in its growth, being categorized in the antagonistic classification scale in grade 1 against all pathogens. Trichoderma sp.1 showed antagonism against Fusarium sp 1 and Fusarium sp.2 while against Botryodiplodia sp. it reached scale 2 at 168 hours. The in vitro test showed that Trichoderma sp. 2 presented greater antagonistic activity due to invasion of spaces and nutrient consumption, parasitism, and antibiosis against the phytopathogens of S. parahybum. The inhibition of radial growth of the phytopathogens exceeded 50% at 24± 2 ° C, and more than 60% at the temperature of 30± 2 ° C. Keywords: Biological control, Fusarium sp., Botryodiplodia sp., Microorganism, percent inhibition of radial growth.

• Autor principal: Intriago Pinargote, Bélgica Cristina (author)
• Format: bachelorThesis
• Idioma: spa
• Publicat: 2021
• Matèries: Control biológico; Fusarium sp; Botryodiplodia sp; Microorganismo
• Accés en línia: https://repositorio.uteq.edu.ec/handle/43000/6327