IV. 5 Coordinator's report: Chromosome 5.

Jens Jensen, Agricultural Research Department, Risø National Laboratory, DK-4000 Roskilde, Denmark.

Trisomic data tentatively place a net-blotch-resistance gene Rpt 2c on chromosome 5 (Bockelman et al. 1977). An additional allele, msg lcz, was reported in the msg1 locus (Hockett 1977). The previously reported alleles in this locus are: msg1ca, -ar, -bp, (Hockett 1973), -i, -t, -ai, and -aw (Hockett 1971). The following new alleles were reported for the cer-zi loci, nos. 701, 1104, 1119, and 1145 (Lundqvist 1977).

The cer-zi locus was located on chromosome 5 in a four-point linkage test; the recombination percentages reported were: cer-zi vs. necl 15.6 + 2.7, necl vs. wst5 32.4 + 2.9, wst5 vs. B 20.5 + 3.0, cer-zi vs. wst5 41.9 + 4.1, necl vs. B 41.0, and cer-zi vs. B 48.6 + 5.0 (Jensen 1978).

A linkage map is prepared by the maximum likelihood map estimation procedure by adding the first three of the above mentioned recombination percentages to the data used to estimate the chromosome 5 map in the last coordinator's report (BGN 7: 86-89, 1977). The previously utilized recombination percentage of 41.2 + 2.4 between wst5 and necl (Jensen 1976) did not fit the map and was omitted. The map is shown in Figure 1. As locus cer-zi is included, the map now has 19 loci. The symbols for the loci on the present map are the same as those on the preceding maps.

Figure 1. The barley chromosome 5 linkage map with the best fit to all available linkage data. All distances are given in centimorgans. The order and positions of some M1 loci and of closely linked loci may not be definite. The position of the centromere is probably slightly above fs2.

References:

Bockelman, H. E., E. L. Sharp, and R. F. Eslick, 1977. Trisomic analysis of genes for resistance to scald and net blotch in several barley cultivars. Can. J. Bot. 55: 2142-2148.

Hockett, E. A., 1971. In: Description of genetic stocks in the barley genetic stock center at Fort Collins, Colorado. BGN 1: 175.

Hockett, E. A., 1973. The genetic male sterile barley collection. BGN 3: 87-89.

Hockett, E. A., 1977. The genetic male sterile collection. BGN 7: 97-100.

Jensen, J., 1976. Recombination estimates from a cross with five linked loci on barley chromosome 5. In: Barley Genetics III, p. 227-234.

Jensen, J., 1978. Location of the eceriferum locus cer-zi on barley chromosome 5. BGN 8:

Lundqvist, U., 1977. Stock list for the eceriferum mutants. IV. BGN 7: 92-96.

BGN 8 toc
BGN Main Index