Submitted to: Journal of the American Society for Horticultural Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 5, 2008
Publication Date: N/A
Interpretive Summary: The pathogen that causes red stele disease of strawberries occurs in different "strains". This research was conducted to help researchers be sure they are working with correctly identified strains. Since different strains of the pathogen react differently to varieties of strwawberries, we used genetics of the strawberry varieties to help identify strains of the pathogen. We produced a DNA fingerprint of each of the ten strawberry varieties that all react differently to different strains of the pathogen causing red stele disease. Scientists can use this to develop new disease resistant strawberry verieties with assurance they are using correctly identified strains of the pathogen.
Ten Fragaria L. (strawberry) differentials for race determination of isolates of Phytophthora fragariae C.J. Hickman var. fragariae, the causal organism of red stele root rot disease, were molecularly characterized with previously published polymerase chain reaction (PCR) based sequence-characterized amplified polymorphism (SCAR) and simple sequence repeat (SSR) markers. The ten strawberry differentials were acquired from the National Clonal Germplasm Repository in Corvallis, OR, along with duplicates of two of the differentials, ‘Blakemore’ and Yaquina B, which were acquired indirectly from another collection at Plant Research International, Wageningen, Gelderland, Netherlands, for comparison and identity confirmation. These two sets of duplicates could not be distinguished molecularly, strongly suggesting they are indeed descended from the same clones. Two of the differentials, Yaquina A and Yaquina B, also could not be distinguished from each other molecularly, supporting recent reports that their reactions to the different pathogen races are similar and that there is very little, if any difference between these two accessions collected from Yaquina Bay, on the Oregon coast.