IV.2 Coordinator's report: Chromosome 5.
Jens Jensen, Agricultural Research Department, Danish Atomic Energy Commission Research Establishment,Risø, DK-4000 Roskilde, Denmark.
To each of the loci cer-e and cer-zi were added three alleles (Lundqvist, 1975); they now have 31 and 10 mutant alleles, respectively. (See descriptions in BGN 5, p. 118 and 145).
A mutant gene for 6-rowed spike (preliminary gene symbol: v3) belongs to a group of five almost similarly behaving 6-rowed mutants. It is reported to be onchromosome 5 (Fukuyama et al., 1972, 1975). These five mutant genes and int-a in the centromere region of chromosome 5 (Persson 1969) are not tested for allelism.
A new short awn gene, ari-a, is associated with chromosome 5 according to Tsuchiya (1975)*, who refers to a Ph.D. thesis of Singh (1974). This gene symbol has, however, already been used for a short awn gene on chromosome 3 (Persson 1969).
A locus controlling the electrophoretic pattern of a group of hordeins in the barley endosperm was linked with the Ml-a locus, 17.4 + 2.8 % recombination (Oram et al., 1975). This locus may belong to the segment designated Pr-a by Solari and Favret (1971).
The linkage data reported by Jensen (1975) from a five-point, a three-point and two two-point linkage tests with genes in the loci f7, trd, B, wst5, and necl were added to the linkage data used to estimate the chromosome 5 map in the last coordinator's report (BGN 5: 72-75, 1975). The data were used in the same way as previously described to estimate the revised linkage map shown in Figure 1. According to Jensen (1976), the centromere is probably between fs2 and Ml-p.
* Association of ari-a with chromosome 5 is a mistake made by Tsuchiya (see Errata, BGN 6: 164 ). Singh (1974) was able to locate ari-a6 in the long arm of chromosome 3. (Editoral note by T. Tsuchiya)
References:
Fukuyama, T. J. Hayashi, I. Moriya, and R. Takahashi, 1972. A test for allelism of 32 induced six-rowed mutants. BGN 2: 25-27.
Fukuyama, T., J. Hayashi, and R. Takahashi, 1975. Genetic and linkage studies of the five types of induced 'six-row' mutants. BGN 5: 12-13.
Jensen, J., 1975. Recombination estimates from a cross with five linked genes on barley chromosome 5. Proc. 3rd Int. Barley Genet. Symp., Munich, July 7-12, 1975 (in press).
Jensen, J., 1976. Additional information on the position of the centromere on barley chromosome 5. BGN 6: 37-38.
Lundqvist, U., 1975. Stock list for the eceriferum mutants. III. BGN 5: 88-90,
Oram, R.N., H. Doll, and B. Køie, 1975. Genetics of two storage protein variants in barley. Hereditas 80: 53-58.
Persson, G., 1969. An attempt to find suitable genetic markers for dense ear loci in barley. I. Hereditas 62: 25-96.
Solari, R.M. and E.A. Favret, 1971. Polymorphism in endosperm proteins of barley and its genetic control. In: Barley Genetics II. Proc. 2nd Int. Barley Genet. Symp. (Ed. R.A. Nilan). Washington State Univ. Press., p. 23-31.
Tsuchiya, T., 1975. Linkage maps of barley as of March 1975. BGN 5: 91-94.
