Alterations in CYP51 gene associated with triazole fungicide performance towards the causative agent of leaf blotch of wheat Mycosphaerella graminicola

Qasim Abdulla Marzani1& Stephen Rossall2


1Department of Plant Protection, College of Agriculture, Salahaddin University - Erbil, Southern Region of Kurdistan - Iraq.

2School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UK.


To explore mutations in the azole performance related CYP51 gene of Mycosphaerella graminicola causes Septoria tritici blotch (STB) in wheat  , 18 isolates of M. graminicola were collected from wheat fields received from Germany, Scotland and England. The gene was amplified by PCR using four primer sets. Each primer was designed to amplify a part of the gene ranging from 555 to 622 bp. The whole CYP51 gene amplicon sequences of the isolates were aligned against the CYP51 of the wild type isolate IPO323 and analyzed using BioEdit software. Fifteen nucleotide sequence alterations were reported in recent UK and German isolates. Some of these mutations were found to be rare, like Y137F, whilst the I381V mutation was found to be increasing with time.

Key Words: CYP51 gene, wheat blotch, Mycosphaerella graminicola, fungicide performance


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