Occurrence of Different Species of Fusarium from Wheat in Relation to Disease Levels Predicted by a Weather-Based Model in Argentina Pampas Region

Abstract

Fusarium head blight (FHB) is an important disease throughout many of the world wheat-growing areas that have humid to semi-humid climate. The infection happens mainly during the anthesis of the wheat, when there have been favorable conditions of moisture and temperature. The direct relation of the infection to environmental factors makes possible the formulation of mathematical models that predict the disease. The causal agent of the FHB of the spike of wheat is attributed principally to Fusarium graminearum. High economic losses due yield decrease have been recorded in Argentina. In the present work, 67 isolates of Fusarium spp. were obtained from samples of wheat grains from Pampas region from 15 locations distributed in Buenos Aires, Entre Ríos, Santa Fe and Córboba provinces during 2006 and 2007 wheat-growing seasons. The identification of species from monosporic isolates was carried out by morphological characterization and use of species-specific PCR-based assays. Both identification criteria were necessary and complementary for the species determination, since in some cases the molecular identification was not specific. Scanty presence of F. graminearum was observed in 2006 wheat-growing season coinciding with the lack of favorable meteorological conditions for producing FHB infection events. High presence of F. graminearum isolates was observed in 2007 wheat-growing season, in accordance with moderate incidence of the disease according to spatial distribution of FHB incidence values. The aim of this report was to identify the causal agent of the FHB disease by different taxonomic criteria and to relate its occurrence with disease incidence values predicted by a weather-based model in Argentina.

Modeling of Yield Losses and Risk Analysis of Fungicide Profitability for Managing Fusarium Head Blight in Brazilian Spring Wheat

“…FHB has been considered a resurgent problem worldwide since the early 1990s with economic losses estimated around $2.7 billion in the United States over a two decade period (McMullen et al 2012). Similar patterns have been reported in wheat and barley regions in South America where the frequency of FHB epidemics increased during the 1990s compared to the previous two decades (Fernandes 1997;Kikot et al 2011;Moschini and Fortugno 1996). Two hypotheses for this resurgence include the wider adoption of conservation tillage practices, as well as the increased use of corn-wheat rotations in North America and Europe (Landschoot et al 2013;Schaafsma et al 2005).…”

A valuable QTL for Fusarium head blight resistance from Triticum turgidum L. ssp. dicoccoides has a stable expression in durum wheat cultivars

“…Increasing occurrence of FHB epidemics has also been associated with crop rotation involving susceptible crops such as corn and soybean, in combination with no-till agriculture that contributes to maintain FHB pathogens inoculum in the soil (Galich 1997;Broders et al 2007). In Argentina, general estimates of yield losses due to FHB in common wheat ranged 20-30% (Galich 1997;Moschini et al 2002;Kikot et al 2011), in some years causing unacceptable levels of deoxynivalenol toxin in the flour (Moschini et al 2013;Martinez et al 2014). Severe FHB epidemics also occurred in durum wheat, with crop losses as high as 70% (Moschini et al 2004).…”

Caracterización y potencialidad de producción de micotoxinas de especies del género Fusarium procedentes de granos de trigo fideo Triticum durum Desf.

“…En la Argentina, F. graminearum sensu stricto (Schwabe), es la especie más frecuentemente relacionada con la enfermedad (Kikot et al, 2011;Kikot, 2012). Sin embargo, a partir de granos infectados se han aislado otras especies menos patogénicas de Fusarium, entre las que se pueden citar F. equiseti, F. poae, F. semitectum, F. cerealis y F. acuminatum.…”

“…En la Argentina, estudios previos han permitido caracterizar las poblaciones de especies del género Fusarium causantes de la FET en trigo pan (Ramírez et al, 2007;González et al, 2008;Kikot et al, 2011;Malbrán et al, 2012;. Sin embargo, se conoce poco sobre la micobiota causante de la enfermedad en trigo fideo y sobre los riesgos potenciales que puedan provocar las especies productoras de micotoxinas (Lori y Sisterna, 2001;Lori et al, 2003;Palacios et al, 2017).…”

“…De las 9 especies de Fusarium halladas en muestras de trigo fideo, 4 de ellas (Lori et al, 1992;de Galich, 1997 (Kikot et al, 2011;Kikot, 2012 (Abramson et al, 1993;Leslie y Summerell, 2006;Bottalico y Perrone, 2002).…”