Author
MEHLENBACHER, SHAWN - OREGON STATE UNIVERSITY | |
BROWN, REBECCA - OREGON STATE UNIVERSITY | |
NOUHRA, EDUARDO - OREGON STATE UNIVERSITY | |
Bassil, Nahla |
Submitted to: International Congress on Hazelnut Proceedings
Publication Type: Abstract Only Publication Acceptance Date: 3/28/2004 Publication Date: 6/14/2004 Citation: Mehlenbacher, S.A., Brown, R.N., Nouhra, E.R., Bassil, N.V. 2004. A linkage map for hazelnut [abstract]. International Congress on Hazelnut Proceedings, June 14-18, 2004, Tarragona, Spain. pg. 45. Interpretive Summary: A seedling population of 144 individuals segregating for resistance to eastern filbert blight caused by the fungus Anisogramma anomala was used to construct the first hazelnut map of the male resistant parent and of the female susceptible parent. A total of 1400 small 10 base pair-long sequences called primers were used to identify random amplified polymorphic DNA (RAPD) markers that segregated in a 1:1 ratio in the population. The map for the resistant parent consists of 245 markers placed in 9 groups. The map for the susceptible parent consists of 189 markers placed in 11 groups. Many individual markers and small groups have not yet been assigned to a group. As additional markers are scored and added to the map, we expect them to merge with the larger groups and form the expected number of 11 groups corresponding to the 11 chromosomes for each parent. An additional 120 markers that segregate 3:1 have been scored but not yet placed on the map. These will allow identification of the corresponding groups in the two parents. Technical Abstract: A linkage map for European hazelnut (Corylus avellana L., 2n = 2x = 22) was constructed using a population of 144 seedlings from a cross of OSU 252.146 x OSU 414.062. The male parent is heterozygous for a dominant gene that confers resistance to eastern filbert blight caused by Anisogramma anomala, and about 50% of the seedlings are resistant. A total of 1400 decamer primers were screened using template DNA of 8 genotypes: resistant parent OSU 414.062, susceptible parent OSU 252.146, three resistant seedlings, and three susceptible seedlings. Primers that generated easily-scored polymorphic bands that appeared to segregate in a 1:1 ratio were identified and used to amplify DNA of all seedlings in the population. The map for the resistant parent consists of 245 loci placed in 9 groups and spans a total of 583 cM. The map for the susceptible parent consists of 189 loci placed in 11 groups and spans a total of 599 cM. Many individual markers and small groups have not yet been assigned to a linkage group. As additional loci are scored and added to the map, we expect them to merge with the larger linkage groups and form the expected number of 11 groups for each parent. An additional 120 markers that segregate 3:1 have been scored but not yet placed on the map. These will allow identification of the corresponding groups in the two parents. |