Plant Disease (2015) 99, 1374-1382

Isabel A. Munck, Philippe Tanguay, Jennifer Weimer, Sara M. Villani and Kerik D. Cox (2015)
Impact of white pine blister rust on resistant cultivated Ribes and neighboring eastern white pine in New Hampshire
Plant Disease 99 (10), 1374-1382
Abstract: To determine the impact of white pine blister rust (WPBR) following the recent breakdown of the Cr resistance dominant gene in cultivated Ribes spp., 255 plants of 19 Ribes cultivars and 445 neighboring eastern white pine (Pinus strobus) from 42 sites across New Hampshire were evaluated. Of the 19 Ribes cultivars evaluated, 15 were WPBR resistant, and 4 of these were labeled as black currant (Ribes nigrum) with the Cr gene (Cr Ribes cultivars). Incidence of WPBR ranged from 0 to 88% for WPBR-resistant Ribes cultivars. Mean WPBR severity was 14 and <6% of leaf area for Cr Ribes and partially resistant cultivars, respectively. The presence of Cronartium ribicola was confirmed on 17 of the 19 Ribes cultivars screened with polymerase chain reaction analysis and DNA sequencing. Reference accessions of Cr Ribes cultivars from the Canadian Clonal Genebank were successfully infected with C. ribicola inoculum collected in New Hampshire from Cr Ribes cultivars and P. strobus, confirming that the vCr race of C. ribicola that has overcome the Cr resistance dominant gene in cultivated Ribes spp. is present in New Hampshire. The probability of finding pine trees with WPBR was greater for trees neighboring infected Cr Ribes cultivars (0.18) than trees neighboring WPBR-free Ribes cultivars (0.02). Results from this study suggest that the breakdown of Cr-based resistance in Ribes spp. poses a threat to the white pine resource and to cultivated Ribes production.
(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): Isabel A. Munck, Philippe Tanguay

Research topic(s) for pests/diseases/weeds:
resistance/tolerance/defence of host
surveys/sampling/distribution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Cronartium ribicola	Currant/gooseberry (Ribes)	U.S.A. (NE)
	Cronartium ribicola	Pine (Pinus)	U.S.A. (NE)