Resistance to benomyl and thiabendazol in isolates of Colletotrichum gloeosporioides (Penz.) Penz. and Sacc. from mango (Mangifera indica L.) in five regions of Mexico.
Gutiérrez-Alonso J. G., Gutiérrez-Alonso O., Nieto-Ángel D., Téliz-Ortiz D., Zavaleta-Mejía E., Delgadillo-Sánchez F., Vaquera-Huerta H.
Author Affiliation: SEMINIS, Estación de Investigación Bajío, Rancho El Refugio, 1a Frac. Apdo. Postal 16, Apaseo El Grande, Guanajuato, México 38160, Mexico.
Revista Mexicana de Fitopatología 21 : 260-266
Abstract : The resistance of C. gloeosporioides [Glomerella cingulata] isolates from diseased mango cv. Haden fruits to benomyl and thiabendazole at 0.1, 1.5, 5, 10, 50, 100, 200 and 400 ppm was evaluated in vitro. Most of the isolates, except Mich, showed a mycelial growth rate of less than 0.5 mm/day with 50 ppm fungicide treatment. Isolates Ver-1, Sin and Mich recorded and LC50 value of 20 ppm for both benomyl and thiabendazole. Isolate Ver-2 did not cross the LC50 of 20 ppm for either fungicides. Isolate Chia exhibited an LC50 value of less than 6 ppm for both fungicides. Neither of the fungicides inhibited conidial germination in vitro, although they caused excessive deformation of the germ tubes. Application of benomyl and thiabendazole did no significantly reduce the anthracnose symptoms in fruits with or without injuries.