Effect of carbendazim resistance on trichothecene production and aggressiveness of Fusarium graminearum.
Fusarium graminearum (teleomorph, Gibberella zeae) causes head blight of cereals and contaminates grains with trichothecene mycotoxins that are harmful to humans and domesticated animals. Control of Fusarium head blight relies on carbendazim (MBC) in China, but resistance to MBC in F. graminearum is now widespread. Sixty-seven strains were evaluated for trichothecene production in shake culture or in the field. The strains included 60 wild-type strains (30 MBC-resistant and 30 MBC-sensitive), three MBC-resistant site-directed mutants at codon 167 in beta(2)-tubulin, three MBC-sensitive site-directed mutants at codon 240 in beta(2)-tubulin, and their MBC-sensitive wild-type progenitor strain ZF21. The incidence of infected spikelets and the amount of F. graminearum DNA in field grain (AFgDNA) also were evaluated for all strains. MBC resistance increased trichothecene production in shake culture or in the field. Although MBC resistance did not change the incidence of infected spikelets, it did increase AFgDNA. Tri5 gene expression increased in MBC-resistant strains grown in shake culture. We found a significant exponential relationship between trichothecene production and Tri5 gene expression in shake culture and a linear relationship between the incidence of infected spikelets or AFgDNA and trichothecene production in field grain.
Zhang
Yan-Jun
YJ
Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insect, Ministry of Agriculture, Nanjing, China.
Yu
Jun-Jie
JJ
Zhang
Yan-Nan
YN
Zhang
Xiao
X
Cheng
Chang-Jun
CJ
Wang
Jan-Xin
JX
Hollomon
Derek W
DW
Fan
Ping-Sheng
PS
Zhou
Ming-Guo
MG
D000935:Antifungal Agents / Q000494:pharmacology*; D001562:Benzimidazoles / Q000378:metabolism / Q000494:pharmacology*; D015139:Blotting, Southern; D002219:Carbamates / Q000378:metabolism / Q000494:pharmacology*; D025141:Drug Resistance, Fungal / Q000187:drug effects*; D005670:Fusarium / Q000187:drug effects* / Q000235:genetics / Q000472:pathogenicity*; D015966:Gene Expression Regulation, Fungal / Q000187:drug effects; D005800:Genes, Fungal; D008826:Microbial Sensitivity Tests; D016297:Mutagenesis, Site-Directed; D015203:Reproducibility of Results; D013997:Time Factors; D014255:Trichothecenes / Q000096:biosynthesis*; D014908:Triticum / Q000382:microbiology
D000935:Antifungal Agents; D001562:Benzimidazoles; D002219:Carbamates; D014255:Trichothecenes; C006698:carbendazim