Peng, J.H., Institute of Evolution, University of Haifa, Mount Carmel, Haifa 31905, Israel
Fahima, T., Institute of Evolution, University of Haifa, Mount Carmel, Haifa 31905, Israel
Röder, M.S., Inst. Plant Genet. Crop Plant Res., Corrensstrasse 3, D-06466 Gatersleben, Germany
Li, Y.C., Institute of Evolution, University of Haifa, Mount Carmel, Haifa 31905, Israel
Dahan, A., Institute of Evolution, University of Haifa, Mount Carmel, Haifa 31905, Israel
Grama, A., Agricultural Research Organization, Volcani Center, P. O. Box 6, Bet Dagan 50250, Israel
Ronin, Y.I., Institute of Evolution, University of Haifa, Mount Carmel, Haifa 31905, Israel
Korol, A.B., Institute of Evolution, University of Haifa, Mount Carmel, Haifa 31905, Israel
Nevo, E., Institute of Evolution, University of Haifa, Mount Carmel, Haifa 31905, Israel

Stripe rust caused by Puccinia striifomis West. is one of the most devastating diseases relating to wheat production. Wild emmer wheat, Triticum dicoccoides, the tetraploid progenitor of cultivated wheat, has proven to be a valuable source of novel stripe-rust resistance genes for wheat breeding. For example, T. dicoccoides accessions from Mt. Hermon, Israel, are uniformly and highly resistant to stripe-rust. The main objective of the present study is to map a stripe-rust resistance gene, derived from the unique Mt. Hermon population of wild emmer, using microsatellite markers. An F2 mapping population was established by crossing stripe-rust resistant T. dicoccoides accession H52 from Mt. Hermon with the Triticum durum cultivar Langdon. The stripe-rust resistance derived from accession H52 was found to be controlled by a single dominant gene which was temporarily designated as YrH52. Out of 120 microsatellite markers tested, 109 (91%) showed polymorphism between the parental lines. Among 79 segregating microsatellite loci generated from 56 microsatellite primer pairs, nine were linked to YrH52 with recombination frequencies of 0.02-0.35, and LOD scores of 3.56-54.22. A genetic map of chromosome 1B, consisting of ten microsatellite loci and the stripe-rust resistance gene YrH52, was constructed with a total map length of 101.5 cM. YrH52 is also closely linked to RFLP marker Nor1 with a map distance of 1.4 cM and a LOD value of 29.62. Apparent negative crossover interference was observed in chromosome 1B, especially in the region spanning the centromere. Negative crossover interference may be a common characteristic of gene-rich regions or gene clusters in specific chromosomes.