Relationship between Fusarium spp. diversity and mycotoxin contents of mature grains in southern Belgium

Abstract

Over a 4-year period (2010-13), a survey aiming at determining the occurrence of Fusarium spp. and their relations to mycotoxins in mature grains took place in southern Belgium. The most prevalent species were F. graminearum, F. avenaceum, F. poae and F. culmorum, with large variations between years and locations. An even proportion of mating type found for F. avenaceum, F. culmorum, F. cerealis and F. tricinctum is usually a sign of ongoing sexual recombination. In contrast, an unbalanced proportion of mating type was found for F. poae and no MAT1-2 allele was present in the F. langsethiae population. Genetic chemotyping indicates a majority of deoxynivalenol (DON)-producing strains in F. culmorum (78%, all 3-ADON producers) and F. graminearum (95%, mostly 15-ADON producers), while all F. cerealis strains belong to the nivalenol (NIV) chemotype. Between 2011 and 2013, DON, NIV, enniatins (ENNs) and moniliformin (MON) were found in each field in various concentrations. By comparison, beauvericin (BEA) was scarcely detected and T-2 toxin, zearalenone and α- and β-zearalenols were never detected. Principal component analysis revealed correlations of DON with F. graminearum, ENNs and MON with F. avenaceum and NIV with F. culmorum, F. cerealis and F. poae. BEA was associated with the presence of F. tricinctum and, to a lesser extent, with the presence of F. poae. The use of genetic chemotype data revealed that DON concentrations were mostly influenced by DON-producing strains of F. graminearum and F. culmorum, whereas the concentrations of NIV were influenced by the number of NIV-producing strains of both species added to the number of F. cerealis and F. poae strains. This study emphasises the need to pay attention to less-studied Fusarium spp. for future Fusarium head blight management strategies, as they commonly co-occur in the field and are associated with a broad spectrum of mycotoxins.

Fusarium Head Blight, Mycotoxins and Strategies for Their Reduction

“…Fusarium graminearum Schwabe usually occurs in warm and hot climate regions, with an average annual temperature above 15 • C, but it is also commonly found in temperate climate countries in the growing seasons characterized by higher temperatures and high humidity. F. graminearum is recognized as the main cause of cereal head blight and maize ear rot in many countries of North and South America, as well as Southern Europe and Asia [1,17,[26][27][28][29][30][31]. Fusarium fujikuroi Nirenberg is also considered a thermophilic species, and high levels of maize ear infection by this fungus and accumulation of fumonisin are often observed in hot and dry vegetation seasons [32].…”

“…Several species can cause head blight, although F. graminearum, F. culmorum and F. avenaceum are the predominant pathogens in most regions of the world [18,25,30,34,[53][54][55][56][57]. In recent years, an increase in the significance of FHB caused by F. poae has been observed, which, by infecting cereal heads and panicles, does not cause fusariosis-like etiological signs and symptoms, and does not significantly affect kernel germination capacity, but contaminates the grain with mycotoxins [46,56,58,59].…”

The adaptation of Fusarium culmorum to DMI Fungicides Is Mediated by Major Transcriptome Modifications in Response to Azole Fungicide, Including the Overexpression of a PDR Transporter (FcABC1)

“…are the species of most concern because, in addition to yield losses, they can produce a wide range of mycotoxins (Desjardins, 2006 ). Fusarium culmorum and F. graminearum (Schwabe), a closely related species, are among the most common species found in Europe, but with high variations between years and locations (Parry et al, 1995 ; Xu et al, 2005 ; Hellin et al, 2016a ). These species can produce the type B trichothecenes deoxynivalenol (DON) or nivalenol (NIV), depending on the strain.…”

Sensitivity of Fusarium culmorum to triazoles: impact of trichothecene chemotypes, oxidative stress response and genetic diversity

“…Most of the strains ( N = 60) originated from Belgium. Some of them, isolated from maize between 2005 and 2012 and from wheat between 2011 and 2013, were retrieved from the Microorganisms and Biological Control (M&BC) collection (Earth and Life Institute, UCL, Belgium). The other strains were kindly provided by various authors.…”

“…This species has historically been considered as the major Fusarium head blight (FHB) pathogen in Europe, but it has gradually been replaced by F. graminearum as a result of the rise in temperature and the increase in maize cultivation . Major outbreaks of F. culmorum , however, were reported on wheat in Belgium and Luxembourg in 2011 . Very dry weather occurred during the wheat flowering period that year and F. culmorum has less need for relative humidity during its infection process than other FHB pathogens .…”