Epidemiology and management of Leptosphaeria maculans (phoma stem canker) on oilseed rape in Australia, Canada and Europe

A - Papers appearing in refereed journals

West, J. S., Kharbanda, P. D., Barbetti, M. J. and Fitt, B. D. L. 2001. Epidemiology and management of Leptosphaeria maculans (phoma stem canker) on oilseed rape in Australia, Canada and Europe. Plant Pathology. 50 (1), pp. 10-27.

AuthorsWest, J. S., Kharbanda, P. D., Barbetti, M. J. and Fitt, B. D. L.
Abstract

Phoma stem canker (blackleg), caused by Leptosphaeria maculans, is an important disease on oilseed rape (canola, rapeseed, Brassica napus, Brassica juncea, Brassica rapa) causing seedling death, lodging or early senescence in Australia, Canada and Europe, but not in China. The two forms of L. maculans (A group and B group) that occur on oilseed rape are now considered to be separate species. The epidemiology and severity of phoma stem canker differs between continents due to differences in the pathogen population structure, oilseed rape species and cultivars grown, climate and agricultural practices. Epidemics are most severe in Australia, where only the A group occurs, and can be damaging in Canada and western Europe, where both A and B groups occur, although their proportions vary within regions and throughout the year. Epidemics are slight in China, where the A group has not been found. Dry climates (Australia, western Canada) lengthen the persistence of infected debris and may synchronize the release of airborne ascospores (after rain) with seedling emergence. L. maculans spreads from cotyledon and leaf infections down petioles to reach the stem, with infections on cotyledons and leaves early in the season producing the most damaging stem cankers at the stem base (crown). Development of both crown cankers and phoma stem lesions higher up stems is most rapid in regions with high temperatures from flowering to harvest, such as Australia and Canada. Breeding for resistance (genetic, disease escape or tolerance), stubble management, crop rotation and fungicide seed treatments are important strategies for control of phoma stem canker in all areas. Fungicide spray treatments are justified only in regions such as western Europe where high yields are obtained, and accurate forecasts of epidemic severity are needed to optimize their use.

KeywordsAgronomy; Plant Sciences
Year of Publication2001
JournalPlant Pathology
Journal citation50 (1), pp. 10-27
Digital Object Identifier (DOI)doi:10.1046/j.1365-3059.2001.00546.x
Open accessPublished as non-open access
Funder project or code424
507
ISSN00320862
PublisherWiley

Permalink - https://repository.rothamsted.ac.uk/item/88742/epidemiology-and-management-of-leptosphaeria-maculans-phoma-stem-canker-on-oilseed-rape-in-australia-canada-and-europe

1 total views
0 total downloads
0 views this month
0 downloads this month