Characterization of Benomyl Resistance in Mycosphaerella fijiensis, Cause of Black Sigatoka of Banana, in Costa Rica

Abstract

Sixty-eight and eighty-six percent of monoascosporic isolates of Mycosphaerella fijiensis from two banana plantations in Costa Rica, in which benomyl was used for ≈10 years to control black Sigatoka, were resistant to benomyl in February and November 1994, respectively. No resistance to benomyl was detected in isolates collected during February 1994 from farms with no history of benomyl use that were located ≈50 km from the nearest banana plantations. Only 1% of isolates was resistant to benomyl in a sample taken during November 1994. In three additional banana farms where benomyl had not been used for 3 to 5 years before sampling, ben-omyl resistance persisted at a high frequency. Benomyl-resistant and -sensitive isolates were distributed equally throughout the range of isolate sensitivity to propiconazole, indicating no relationship between resistance to benomyl and lower sensitivity to propiconazole but double resistance to these two compounds. Five benomyl-resistant and five benomyl-sensitive isolates of M. fijiensis were inoculated to banana plants under greenhouse conditions. Benomyl-resistant isolates were more aggressive than benomyl-sensitive isolates, as determined by measures of disease severity, incubation time, and number of lesions at 40 days after inoculation.

Sensitivity of Colletotrichum spp. Isolated from Grapes in Korea to Carbendazim and the Mixture of Carbendazim Plus Diethofencarb

“…Koenraadt et al (1992) identified strains of Venturia inaequalis resistant to benomyl in an orchard more than 10 years after benomyl use had been discontinued. In Mycosphaerella fijiensis from banana plantations where benomyl had been used for approximately 10 years to control black Sigatoka disease, 86% of isolates were resistant to benomyl, whereas no resistance was detected in isolates collected from plantations with no history of benomyl use (Romero and Sutton, 1998). In C. cereale causing turfgrass anthracnose, the difference in the prevalence of benomyl resistance among sampling sites also reflected the cumulative effects of benomyl use (Wong et al, 2008).…”

Chemical management in fungicide sensivity of Mycosphaerella fijiensis collected from banana fields in México

“…There are several reports showing local aspects of fungicide resistance in isolates of M. fijiensis collected in America and other parts of the world (Romero and Sutton, 1997, 1998; Chin et al , 2001; Pérez et al , 2003; Vawdrey and Grice, 2005; Amil et al , 2007). However in Mexico, a few studies focussed on the current situation of fungicides resistance in M. fijiensis populations have been conducted (Manzo-Sánchez et al , 2012; Martínez-Bolaños et al , 2012).…”

Genetic analysis of Mycosphaerella fijiensis in the Ugandan Lake Victoria region

“…Benomyl (a systemic benzimidazole fungicide) was used extensively in the 1970s to 1990s for control of black Sigatoka in many countries, but was gradually losing its efficacy because of expanding resistant fungal populations, particularly in some Latin American locations (Stover, 1977; Rodríguez & Jiménez, 1985; Romero & Sutton, 1998). Given that the introduction of the disease to Africa is considered to have originated from South East Asia via Central America (Rivas et al ., 2004), it was of interest to investigate whether the pathogen population studied here contained individuals harbouring resistance to this fungicide.…”