Phylogenetic analyses and toxigenic profiles of Fusarium equiseti and Fusarium acuminatum isolated from cereals from Southern Europe

摘要

Fusarium equiseti and Fusarium acuminatum are toxigenic species that contaminate cereal crops fromuddiverse climatic regions. They are common in Spanish cereals. The information available on theirudphylogenetics and toxigenic profiles is, however, insufficient to assist risk evaluation. In this work,udphylogenetic analyses were performed using partial sequences of the translation elongation factor geneud(EF-1a) of F. equiseti and F. acuminatum strains isolated from barley and wheat from Spain and otherudcountries. The Northern and Southern European F. equiseti strains largely separated into two phylogeneticallyuddistinct clusters. This suggests the existence of two distinct populations within this species,udexplaining its presence in these regions of markedly different climate. Production of type A and Budtrichothecenes by the Spanish strains, examined in wheat cultures using a multitoxin analytical method,udindicated that F. equiseti could produce deoxynivalenol and nivalenol and other trichothecenes, atudconcentrations that might represent a significant risk of toxin contamination for Southern Europeanudcereals. F. acuminatum showed low intraspecific genetic variability and 58% of the strains could produceuddeoxynivalenol at low level. Neither species was found to produce T-2 or HT-2 toxins. The present resultsudprovide important phylogenetic and toxigenic information essential for the accurate prediction ofudtoxigenic risk.