Barley genome mapping of the North American Barley Genome Mapping Project (NABGMP) is based on three crosses derived from four parents. These are Steptoe × Morex, Harrington × TR306, and Harrington × Morex. The Steptoe × Morex cross is the most extensively mapped with 385 markers. The Harrington × TR306 cross has approximately 130 markers and work on the Harrington × Morex cross is just starting.

The Steptoe × Morex map and description of the first 200 markers was published in BGN 21. A 295 marker map is in press in Theoretical and Applied Genetics. Here we present the 385 marker Steptoe × Morex map (Figs. 1-7) and descriptions of markers 201 to 385 (Table 1). The distribution of the 350 markers to individual chromosomes and their genetic lengths in centiMorgans are shown in Table 2.

A Steptoe × Morex skeletal map based on 129 markers is also presented (Fig. 8). The markers used were selected for uniform distribution throughout the genome and for their hybridization quality (indicated by a letter in parenthesis after the marker name; E = excellent; G = good; F = fair; P = poor). In a few cases fair or poor quality markers had to be used since they were the only ones available in that region. These will be replaced as soon as possible. The skeletal map should be useful for screening the genome to find tags for useful genes and for QTL mapping.

Acknowledgements - The authors listed are members of my laboratory who assisted in compiling data and preparation of maps. Mapping data, used to prepare these maps and added since the 295 marker map published in Theoretical and Applied Genetics, 1993, were also contributed by M. Saghai Maroof, L. Dahleen, and D. Hoffman laboratories. Special thanks to Dr. Andreas Granerfor providing many excellent probes from their barley mapping program. Thanks are also due to all the members of NABGMP who assisted in characterization of probes and correcting errors.

Steptoe × Morex 129 Market Skeletal Map

Table 1. Description of markers 201-385
mapped to the Steptoe × Morex cross

Table 2. Distribution of markets and genetic lengths
of the seven barley chromosomes

---

table of contents | BGN main index