Citation
Jurado García-Posada, Miguel and Marín, Patricia and González Jaén, María Teresa
(2015).
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.
"International Journal of Food Microbiology", v. 195
;
pp. 40-47.
ISSN 0168-1605.
https://doi.org/10.1016/j.ijfoodmicro.2014.11.027.
Abstract
Fusarium equiseti
is a toxigenic species that often contaminates ce
real 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 pro
file 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
potentialregimens(−0.7,−2.8,−7.0,and −9.8MPa,correspondingto
0.99,0.98,0.95 and 0.93aw values).Growth
was observed at all temperatures except at 40 °C, and at all the solute potential values except at−9.8 MPa when
combined with 15 °C. Optimal growth was observed at 20–
30 °C and −0.7/−2.8 MPa. 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 −9.8 MPa on wheat
and barley based media. Induction of
TRI5
expression was detected between 25 and 35 °C and −0.7 and
− 2.8 MPa, with maximum values at 35 °C and −2.8 MPa 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.