Open Access Repository

Baseline sensitivity of Australian Phoma ligulicola isolates from pyrethrum to azoxystrobin and difenoconazole


Downloads per month over past year

Jones, SJ, Pethybridge, SJ, Hay, FS, Groom, T and Wilson, CR 2007 , 'Baseline sensitivity of Australian Phoma ligulicola isolates from pyrethrum to azoxystrobin and difenoconazole' , Journal of Phytopathology, vol. 155 , pp. 377-380 , doi: 10.1111/j.1439-0434.2007.01241.x.

[img] PDF
3942.pdf | Request a copy
Full text restricted
Available under University of Tasmania Standard License.


Ray blight caused by Phoma ligulicola is an important
disease of pyrethrum in Australia, and successful
management relies upon the fungicides, azoxystrobin
and difenoconazole. Azoxystrobin and difenoconazole
were introduced into pyrethrum production in 2001.
The sensitivity of P. ligulicola isolates collected in
2003 to azoxystrobin (n ¼ 56) and difenoconazole
(n ¼ 61) was tested. Testing for sensitivity to
azoxystrobin and difenoconazole used a conidial
germination and mycelial growth assay respectively.
For each fungicide, the effective dose required to
reduce mycelial growth or conidial germination by
50% (EC50) was determined by probit analysis. The
EC50 values ranged from 0.007 to 0.193 lg/ml for
azoxystrobin and 0.04 to 13.8 lg/ml for difenoconazole.
No evidence was found for cross-resistance
between azoxystrobin and difenoconazole in this
baseline population. This information serves as
important baseline data for tracking future changes
in sensitivities of P. ligulicola to these fungicides.

Item Type: Article
Authors/Creators:Jones, SJ and Pethybridge, SJ and Hay, FS and Groom, T and Wilson, CR
Journal or Publication Title: Journal of Phytopathology
Publisher: Blackwell Verlag GmbH
ISSN: 0931-1785
DOI / ID Number: 10.1111/j.1439-0434.2007.01241.x
Additional Information:

The definitive version is available online at

Item Statistics: View statistics for this item

Actions (login required)

Item Control Page Item Control Page