Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias
Abstract
The nematode control using fungi is one alternative to prevent anthelmintic resistance. The purpose of this study was to evaluate the in vitro predacious ability of Duddingtonia flagrans against Haemonchus and Cooperia infective larvae, by both visualizing and measuring the larvae trapping activity (LTA) and by the nematode populations reduction in different culture media. These experiments were carried out at the Autonomous University of Chapingo in Teapa, Tabasco, Mexico. One D. flagrans Mexican strain was used in the two trials. In the first trial, LTA was visualized and measured under the microscope and observations were described. In the second trial, a reduction of the nematode population by the fungal activity was evaluated using three different culture media: water agar (WA), corn meal agar (CMA), and dextrose potato agar (DPA) at 3 different recovery times (24, 48, and 96 h). In the first trial, both rings and adhesive loops were observed, as well as larvae trapped in such structures. The LTA was higher at 48 h (68.4 ± 16.0 %) as compared to that found at 24 h (41.1 ± 19.9 %, PEl control biológico de nematodos con hongos es una alternativa para evitar la resistencia antihelmíntica. El objetivo de la presente investigación fue conocer la capacidad depredadora de Duddingtonia flagrans contra cultivos de Haemonchus y Cooperia, al estimar el porcentaje de reducción de poblaciones de nematodos en diferentes medios de cultivo. El experimento se llevó a cabo en la Universidad Autónoma Chapingo en Teapa, Tabasco, México. Se utilizó una cepa mexicana de D. flagrans que se sometió a dos pruebas, en la primera se contaron directamente larvas atrapadas, libres, enroscadas y muertas. En la segunda se desafió el hongo con nematodos en tres diferentes medios: agua-agar (AA), harina de maíz-agar (HMA) y papa-dextrosa-agar (PDA) a tres tiempos de recuperación (24, 48 y 96 h). En la primera prueba se observaron anillos y redes, así como larvas atrapadas en esas estructuras. El porcentaje de larvas atrapadas fue mayor a las 48 h (68.4 ± 16.0) respecto a las 24 h (41.1 ± 19.9,
