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Environmental conditions in Sardinia (Tyrrhenian Islands) are conducive to fusarium root rot (FRR) and fusarium head blight (FHB). A monitoring survey on wheat was carried out from 2001 to 2013, investigating relations among these diseases and their causal agents. FHB was more frequently encountered in the most recent years while FRR was constantly present throughout the monitored period. By assessing the population composition of the causal agents as well as their genetic chemotypes and EF-1a polymorphisms, the study examined whether the two diseases could be differentially associated to a species or a population. Fusarium culmorum chemotypes caused both diseases and were detected at different abundances (88% 3-ADON, 12% NIV). Fusarium graminearum (15-ADON genetic chemotype) appeared only recently (2013) and in few areas as the causal agent of FHB. In F. culmorum, two haplotypes were identified based on an SNP mutation located 34 bp after the first exon of the EF-1a partial sequence (60% adenine, 40% thymine); the two populations did not segregate with the chemotype but the A-haplotype was significantly associated with FRR in the Sardinian data set (P = 0Á001), suggesting a possible fitness advantage of the A-haplotype in the establishment of FRR that was neither dependent on the sampling location nor the sampling year. The SNP determining the Sardinian haplotype is distributed worldwide. The question whether the A-haplotype segregates with characters facilitating FRR establishment will require further validation on a specifically sampled international data set.

Random amplification of polymorphic DNA (RAPD-PCR) analysis was conducted on 48 isolates of Fusarium oxysporum f. sp. radicis-lycopersici (F.o.r.l.) from different geographic regions, representing all known vegetative compatibility groups (

High-throughput methods are needed for functional genomics analysis in Fusarium culmorum, the cause of crown and foot rot on wheat and a type B trichothecene producer. Our aim was to develop and test the efficacy of a double-component system based on the ability of the impala transposase to transactivate the miniature inverted-repeat transposable element mimp1 of Fusarium oxysporum. We report, for the first time, the application of a tagging system based on a heterologous transposon and of splinkerette-polymerase chain reaction to identify mimp1 flanking regions in the filamentous fungus F. culmorum. Similar to previous observations in Fusarium graminearum, mimp1 transposes in F. culmorum by a cut-and-paste mechanism into TA dinucleotides, which are duplicated on insertion. mimp1 was reinserted in open reading frames in 16.4% (i.e. 10 of 61) of the strains analysed, probably spanning throughout the entire genome of F. culmorum. The effectiveness of the mimp1/impala double-component system for gene tagging in F. culmorum was confirmed phenotypically for a putative aurofusarin gene. This system also allowed the identification of two genes putatively involved in oxidative stress-coping capabilities in F. culmorum, as well as a sequence specific to this fungus, thus suggesting the valuable exploratory role of this tool.