title: Growth rate and TRI5 gene expression profiles of Fusarium equiseti strains isolated from Spanish cereals cultivated on wheat and barley media at different environmental conditions.
abstract: Fusarium equiseti is a toxigenic species that often contaminates cereal crops from diverse climatic regions such as Northern and Southern Europe. Previous results suggested the existence of two distinct populations within this species with differences in toxin profile which largely corresponded to North and South Europe (Spain). In this work, growth rate profiles of 4 F. equiseti strains isolated from different cereals and distinct Spanish regions were determined on wheat and barley based media at a range of temperatures (15, 20, 25, 30, 35 and 40°C) and water potential regimens (-0.7, -2.8, -7.0, and -9.8MPa, corresponding to 0.99, 0.98, 0.95 and 0.93 aw values). Growth was observed at all temperatures except at 40°C, and at all the solute potential values except at -9.8MPa when combined with 15°C. Optimal growth was observed at 20-30°C and -0.7/-2.8MPa. The effect of these factors on trichothecene biosynthesis was examined on a F. equiseti strain using a newly developed real time RT-PCR protocol to quantify TRI5 gene expression at 15, 25 and 35°C and -0.7, -2.8, -7.0 and -9.8MPa on wheat and barley based media. Induction of TRI5 expression was detected between 25 and 35°C and -0.7 and -2.8MPa, with maximum values at 35°C and -2.8MPa being higher in barley than in wheat medium. These results appeared to be consistent with a population well adapted to the present climatic conditions and predicted scenarios for Southern Europe and suggested some differences depending on the cereal considered. These are also discussed in relation to other Fusarium species co-occurring in cereals grown in this region and to their significance for prediction and control strategies of toxigenic risk in future scenarios of climate change for this region.
authors.affiliation: Department of Genetics, Faculty of Biology, Complutense University of Madrid (UCM), José Antonio Novais 12, 28040 Madrid, Spain.
authors.forename: Patricia
authors.initials: P
authors.lastname: Marín
authors.affiliation: Department of Science and Technology applied to Agricultural Engineering, EUIT Agrícola, Technical University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Jurado
authors.affiliation: Department of Genetics, Faculty of Biology, Complutense University of Madrid (UCM), José Antonio Novais 12, 28040 Madrid, Spain. Electronic address: tegonja@ucm.es.
authors.forename: M Teresa
authors.initials: MT
authors.lastname: González-Jaén
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D003470:Culture Media / Q000737:chemistry / Q000378:metabolism; D002523:Edible Grain / Q000382:microbiology*; D004777:Environment; D005670:Fusarium / Q000235:genetics* / Q000254:growth & development* / Q000302:isolation & purification; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D001467:Hordeum / Q000737:chemistry / Q000378:metabolism; D013030:Spain; D013696:Temperature; D014908:Triticum / Q000737:chemistry / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media
keywords: Cereal based media; Environmental factors; F. equiseti; Growth rate; Real time RT-PCR; TRI5 expression