Since the last reports from 1991 and 1992 not many new localizations or allelic tests have beenmade or reported.

The glossy sheath/spike gene, gs6, (BGS 356), is reported to be located on chromosome 2, probably at the end of the short arm (Tsuchiya 1971, von Wettstein-Knowles, 1992; Franckowiak, personal communication). Eslick (1974) reported that the gene gs6 and the eceriferum cer-c gene are allelic. In Sweden, the glossy sheath/spike gene gs6 was tested against the Swedish eceriferum loci with the same phenotype. In the F₁ generation in 1992 and in the F₂ generation 1993, all plants of two alleles at the eceriferum locus cer-c in combination with gs6 were glossy sheath/spike or waxless, while the F₁ plants of crosses to representatives of all the other loci, cer-q and cer-u inclusively with the same glossy sheath/spike phenotype had normal wax layer, and the F₂ generation segregated in normal and waxless plants in good Mendelian ratios. The loci cer-c, cer-q and cer-u are the most frequently mutated loci within this phenotype and closely linked. Thus, it can be settled that gs6 is allelic to the Swedish eceriferum locus cer-c.

Totally, 1890 different eceriferum or waxless mutants are existing in the Swedish mutation collection, 1580 of them are localized to 79 different cer loci. They comprise at least five different phenotype categories. All the mutant stocks are increased during several years, and their seeds are incorporated into the Nordic Gene Bank. The morphological description and their genetical analyses are documented in a database. The material is available for every barley research worker and requests of eceriferum mutant seed stocks can be sent to the coordinatorfor eceriferum genes. Every contribution and research report for these genes are welcome.

References:

Eslick, R.F. 1974. Allele tests of gs and cer mutants. BGN 4: 9 - 11.

Mc.Proud, Wayne L. and Eslick R.F. 1971. Allelism within series of glossy sheath mutants. BGN 1: 31 - 35.

Rasmusson, D.C. and Lambert, J.W. 1965. Inheritance of the Glossy Sheath Character in Barley, Hordeum vulgare L. Crop Science 5: 251 - 253.

Takahashi, R., Hayashi, J. and Moriya, 1. 1972. New linkage studies obtained in 1971. BGN 2: 74 - 76.

Tsuchiya, T. 1971. Cytogenetics of telotrisomics in barley. BGN2: 93 - 98.

Wettstein-Knowles, P. von. 1992. Cloned and mapped genes: current status. In: Barley: Genetics, Biochemistry, Molecular Biology and Biotechnology. (Ed. P.R. Shewry). CAB International, Wallingford, Oxon, UK. p. 73 - 98.