Canadian Journal of Plant Pathology (2000) 22, 387-391

D.M. Earnshaw, M.R. McDonald and G.J. Boland (2000)
Interactions among isolates and mycelial compatibility groups of Sclerotium cepivorum and cultivars of onion (Allium cepa)
Canadian Journal of Plant Pathology 22 (4), 387-391
Abstract: One hundred and sixty-nine isolates of Sclerotium cepivorum were evaluated for the ability to incite lesions of white rot of onion in three commercial cultivars of onion (Norstar, Benchmark, and Fortress), using a controlled environment, detached onion scale assay. All isolates incited lesions on detached onion scale segments, but isolate, cultivar, and isolate x cultivar interactions were observed when lesion diameter was measured 7 days post-inoculation. Lesion diameters ranged from 6.4 to 39.0 mm. When averaged across mycelial compatibility groups (MCGs), differences in mean lesion diameters were observed among the nine MCGs and three cultivars, but there were no MCG x cultivar interactions. When averaged across MCGs, mean lesion diameter was greatest on cv. Norstar, followed by cvs. Benchmark and Fortress. The results establish that significant differences and, in some cases, interactions can be detected among isolates and MCGs of S. cepivorum and cultivars of A. cepa, using a detached onion scale assay in controlled environments. Preliminary results indicated that these controlled environment assessments are correlated with field assessments of at least some of the same cultivars and breeding lines.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Greg J. Boland, Mary Ruth McDonald

Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution
resistance/tolerance/defence of host

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Stromatinia cepivora	Onion/garlic/leek (Allium)