Impact of environmental factors and fungicides on growth of two Fusarium proliferatum strains isolated from Argentinian wheat grains

CENDOYA E.; ZACHETTI V.G.L.; NICHEA M.J.; FARNOCHI, M.C; RAMIREZ M. L.

Freising

Workshop; International Commision in Food Mycology. Whorshop 2016; 2016

International Commission on Food Mycology

Wheat is an important grain cereal mostly used for human consumption. During non-FHB epidemic years the predominant Fusarium species is F. proliferatum. This species is able to produce fumonisins, which are mycotoxins that can cause various adverse health effects in animals and humans. There is also evidence of fumonisin contamination in wheat grains and wheat-based products. The use of fungicides is a complementary control measure when weather conditions are conducive to FHB infection from anthesis to harvest. In this study, the impact of four commercial fungicides used for controlling FHB (epoxiconazole + metconazole, tebuconazole, pyraclostrobin + epoxiconazole, and prothioconazole) on growth of two F. proliferatum strains was evaluated in relation to water activity (aW; 0.99, 0.97, 0.95) and temperature (15°C and 25°C) on a wheat-based media. Both strains showed a similar behavior in all tested conditions. All fungicides reduced growth rates when compared to the control, with the exception of tebuconazole used in the lowest concentration at 15 °C. This reduction increased as the fungicide concentration increased. The best fungicide resulted to be prothioconazole, because it was able to inhibited fungal growth at 15°C in all tested conditions, and at 25°C at the lowest aW tested. Our results show that reduction in growth rate in the presence of fungicides is influenced by complex interactions between aW, temperature, and fungicide concentration in both F. proliferatum strains. Such information could be useful for effective control of F. proliferatum growth and possible fumonisin production on wheat grains.