Ndoye M.,Molecular Biotechnology Laboratory of Triticeae Crops |
Zhang J.-B.,Molecular Biotechnology Laboratory of Triticeae Crops |
Zhang J.-B.,Huazhong Agricultural University |
Wang J.-H.,Molecular Biotechnology Laboratory of Triticeae Crops |
And 8 more authors.
Journal of Phytopathology | Year: 2012
Fusarium graminearum clade species are among the main causative agents of Gibberella ear rot (GER) in maize and responsible for the various trichothecene mycotoxins accumulated in contaminated maize grains. In this study, a total of 620 isolates from diseased maize ears collected from 59 districts in 19 provinces throughout China, previously identified morphologically as Fusarium graminearum clade, was genetically characterized at the species level based on SCAR (Sequence Characterized Amplified Region) and for their potential capability of mycotoxin production using the genetic chemotyping assay. The results showed that 359 isolates were F. asiaticum (SCAR 5), which consisted of 97% nivalenol (NIV)-chemotypes, 0.8% 3-acetyldeoxynivalenol (3-ADON)-producing isolates and 2.2% 15-acetyldeoxynivalenol (15-ADON) producers, whereas the remaining 261 isolates were identified as F. graminearum sensu stricto (SCAR 1), all of which produced 15-ADON mycotoxins. This high proportion of NIV producers present in F. asiaticum is different from the chemotype patterns in F. asiaticum populations isolated from wheat and barley, where DON and its acetylated chemotypes were the predominant mycotoxins. Moreover, the majority of NIV producers (59.1%) and all the 3-ADON-producing strains were derived from the warmer regions in southern China, whereas most of the 15-ADON-producing strains (78.4%) were isolated from the colder regions in northern China. Our study is the first report of NIV chemotypes of F. asiaticum and 15-ADON chemotypes of F. graminearum sensu stricto that were associated with the GER of maize in China. © 2012 Blackwell Verlag GmbH.
Gao C.-S.,Molecular Biotechnology Laboratory of Triticeae Crops |
Kou X.-J.,Molecular Biotechnology Laboratory of Triticeae Crops |
Kou X.-J.,Huazhong Agricultural University |
Li H.-P.,Molecular Biotechnology Laboratory of Triticeae Crops |
And 4 more authors.
Plant Pathology | Year: 2013
In this study, the Arabidopsis thaliana NPR1 (non-expressor of PR genes) gene was integrated into an elite wheat cultivar, and the response of the transgenic wheat expressing NPR1 to inoculation with Fusarium asiaticum was analysed. With seedling inoculation, the transgenic lines showed significantly increased fusarium seedling blight (FSB) susceptibility, whereas floret inoculation resulted in enhanced fusarium head blight (FHB) resistance. Quantitative real-time PCR revealed that expression of two defence genes, PR3 and PR5, was associated with susceptible reactions to FSB and FHB, whereas the PR1 gene was activated in resistance responses. This inverse modulation by the constitutively expressed NPR1 gene suggests that NPR1 has a bifunctional role in regulating defence responses in plants. Therefore, it is unsuitable for improving overall resistance to FSB and FHB in wheat. © 2012 The Authors. Plant Pathology © 2012 BSPP.