Premium
Sterol Composition of DMI‐Resistant and ‐Sensitive Field Isolates of Cercospora beticola
Author(s) -
Karaoglanidis G. S.,
MenkissogluSpiroudi U.,
Thanassoulopoulos C. C.
Publication year - 2003
Publication title -
journal of phytopathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.53
H-Index - 60
eISSN - 1439-0434
pISSN - 0931-1785
DOI - 10.1046/j.1439-0434.2003.00746.x
Subject(s) - sterol , biology , ergosterol , demethylase , biochemistry , composition (language) , cholesterol , gene , epigenetics , linguistics , philosophy
The effect of the sterol 14 α ‐demethylase‐inhibitor (DMI) fungicide flutriafol, on the sterol composition of DMI‐sensitive and ‐resistant strains of Cercospora beticola , was studied. In the absence of flutriafol, these strains had the same sterol composition regardless of their sensitivity to DMIs, with ergosterol the major sterol in the fungal membranes. Following treatment with flutriafol, the desmethyl sterols decreased and the eburicol, obtusifoliol and 14 α ‐methylergosta‐8,14, 24(28)‐trienol content increased, indicating that sterol 14 α ‐demethylase activity was inhibited in all C. beticola strains tested. In the resistant strains, C14‐methyl‐sterols accumulated at a higher flutriafol concentration than they did in the sensitive strains. The results demonstrate that DMI‐resistance in C. beticola is not conferred a sterol 14 α ‐demethylase deficiency, suggesting an alternative mechanism in the observed resistance phenotypes.