Abstract
The genetic basis of virulence of 24 isolates of L. maculans collected from various sites throughout south-eastern and south-western Australia were studied using five clone-lines of B. napus. The experimental design allowed the estimation of the environmental and genetic components of variance using a standard analysis of variance. Virulence of these isolates (as measured by the percentage of stem girdling, %G) on the clonelines NCII and Tap was found to be most likely controlled by a small number of genes; the broad-sense heritabilities were 79.7% and 67.5% for virulence on NCII and Tap, respectively. The significance of these results in relation to the potential of L. maculans in adapting to new resistant B. napus cultivars is discussed.
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Pang, E.C.K., Halloran, G.M. Genetics of virulence in Leptosphaeria maculans (Desm.) Ces. et De Not., the cause of blackleg in rapeseed (Brassica napus L.). Theoret. Appl. Genetics 93, 301–306 (1996). https://doi.org/10.1007/BF00223169
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DOI: https://doi.org/10.1007/BF00223169