Effect of pydiflumetofen onGibberella ear rot andFusarium mycotoxin accumulation in maize grain
2021; Volume: 14; Issue: 4 Linguagem: Inglês
10.3920/wmj2020.2638
ISSN1875-0796
AutoresKatiani Eli, A. W. Schaafsma, Victor Limay‐Rios, David C. Hooker,
Tópico(s)Plant Disease Resistance and Genetics
ResumoIn Ontario, Canada, Fusarium graminearum Schwabe causes Gibberella ear rot (GER) in maize, resulting in the accumulation of mycotoxins, mainly deoxynivalenol (DON), DON-3-glucoside (DON-3G) and zearalenone (ZEN) in infected kernels. Fungicides can be an important tool for managing GER and DON and other Fusarium mycotoxins in maize. Until recently, all fungicides available to growers were triazoles, thus no resistance management strategy through fungicide use was possible. In this study, a novel carboxamide fungicide active ingredient (pydiflumetofen) was evaluated against conventional triazole fungicides and mixtures for: (1) effectiveness on mycotoxins (2) optimal application timing; and (3) efficacy of application, with and without an insecticide, under natural and inoculated-misted conditions. The best timing for fungicide application was at full silk, resulting in the highest reduction of GER symptoms and lowest accumulation of F. graminearum mycotoxins in harvested grain. DON and DON-3G concentrations were reduced by at least 50% with a fungicide application at full silk. Fungicide treatments did not affect fumonisin concentrations in grain. Pydiflumetofen (94 g active ingredients (AI)/ha) and fungicides containing pydiflumetofen (75-94 g AI/ha) were similar to standard triazole fungicides (prothioconazole at 200 g AI/ha and metconazole at 90 g AI/ha) for reducing GER and F. graminearum mycotoxins under misted-inoculated plots and commercial field conditions; as a result, we expect pydiflumetofen to be competitive with triazole-only chemistries in the marketplace, which should delay the onset of fungicide resistance.
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