Prochloraz Insensitivity in Isolates of the Cereal Eyespot Fungus, Pseudocercosporella Herpotrichoides, in New Zealand

A survey of eyespot-infected cereal crops in Southland during Jan. 1985 found a number of isolates of the pathogen able to grow on agar medium containing this broad spectrum imidazole fungicide. Of 31 isolates tested, 26 showed some growth on agar containing prochloraz at 2 micro g/ml and 18 of these (from both barley and wheat) grew at concn more than or equal to 20 micro g/ml. This is in contrast to an earlier survey in 1984 in which all 11 isolates tested were sensitive to prochloraz. Of the 26 insensitive isolates from the 1985 survey, 2 were also insensitive to benomyl at 200 micro g/ml. Australasian Plant Pathology 15(1) 22 - 23 Full text doi:10.1071/APP9860022 © CSIRO 1986