Identification and Development of PCR-based Markers Linked to Eastern Filbert Blight Resistance in Hazelnut

Download or read book Identification and Development of PCR-based Markers Linked to Eastern Filbert Blight Resistance in Hazelnut written by Joel W. Davis and published by . This book was released on 1998 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using bulked segregant analysis, five RAPD markers were identified that were linked in coupling to a gene conferring complete resistance to eastern filbert blight caused by Anisogramma anomala (Peck) E. Muller in hazelnut (Corylus avellana L.). Two modified backcross populations were inoculated and scored for resistance to the pathogen and found to segregate in a 1:1 ratio. In the first population, the five markers were linked to the resistance gene at distances of 6.7, 0, 2.0, 2.0, and 2.0 cM. Three of these markers also were linked in coupling in the second population at distances of 6.0, 6.0, and 4.0 cM. Two of these markers were cloned and sequenced, and primers were designed based on the sequence information at the termini of the amplified marker fragments. These primers were used to amplify DNA from both populations and evaluated for their potential use in selecting for resistance among seedlings. One of these cloned markers (SC152800) produced the same polymorphism among both populations and was consistent with the linkage exhibited by the original RAPD marker. These primers were also used to amplify DNA from a collection of germplasm accessions used in the hazelnut breeding program. A fragment of similar size was amplified in all of the resistant germplasm tested, and also in some of the susceptible selections. This marker was shown to have potential for use in marker-assisted selection for breeding hazelnut cultivars resistant to eastern filbert blight.