The group of ear morphology genes comprises a fairly large number of different characters. Many barley research workers all over the world have been dealing with many of these characters. In this volume I am shortly reporting on the Swedish collection of the ear morphology genes which has successfully been brought together during more than 60 years of Swedish mutation research. The following list shows the different types in this Swedish collection:

1. Mutants with changes in the spike and spikelets: dense spikes (Erectoides), lax spikes (Laxatum), six-row types (Hexastichon), intermedium, types, irregular spikes (Irregulare), curly spikes, double seeds in the tip, Calcaroides, Bracteatum and Semibracteatum or third outer glume, Macrolepis or lemmalike glumes, extra floret, accordeon rachis, opposite-sited spikelets, semideficiens, deficiens, acute lemma, large and curled laterals, many glumes on the laterals, prolongated glumes, triaristatum, short and long spikes. Totally, there are 24 subtypes with about 3971 isolated mutants.
2. Mutants with changes in the awns: short awns (Breviaristatum), long awns, dehiscent awns, smooth awns, curly awns, wilting and soft awns, yellowing awns. Totally, there are 8 subtypes with about 580 mutation cases.
3. Mutants with changes in seed size and shape: globe shaped grains (Globosum), small seeds, large seeds, oblonged seeds, semi-naked caryopsis. Totally, there are 5 subtypes with about 405 mutation cases.

Also all the ear morphological mutants stocks have become increased during the last years and are incorporated into the Nordic Gene Bank. The morphological description and their genetical analyses are documentated in various databases. Every barley research worker is welcome to use the material for different research studies not least for biochemical genetics and molecular biological studies. Requests of ear morphology gene mutant seed stocks can be sent to the coordinator for ear morphology genes. Every contribution and research report for these categories of genes are welcome.

References:

Gustafsson, Å. and Lundqvist, U., 1980. Hexastichon and intermedium mutants in barley. Hereditas 92: 229 - 236.

Gustafsson, Å., Hagberg, A., Lundqvist, U. and Persson, G., 1969. A proposed system of symbols for the collection of barley mutants at Svalöv. Hereditas 62: 409 - 414.

Kucera, J., Lundqvist, U. and Gustafsson, Å., 1975. Induction of breviaristatum mutants in barley. Hereditas 80: 263 - 278.

Lundqvist, U., 1991. Swedish mutation research in barley with plant breeding aspects. A historical review. In: Plant Mutation Breeding for Crop Improvement. Proc. Int. Symp. Vienna, 1990, IAEA. Vienna. p. 135 - 148

Lundqvist, U., 1992a. Coordinator's report: Ear morphology genes. BGN 22:

Lundqvist, U., 1992b. Mutation Research in Barley. Doctoral Thesis, The Swedish University of Agricultural Sciences, Svalöv and Uppsala, Sweden, pp. I - 283.

Lundqvist, U. and Lundqvist, A., 1987. Barley mutants - diversity and genetics. Barley Genetics V. Proc. Fifth Int. Barley Genet. Symp., Okayama 1986. (Eds. S. Yasuda and T. Konishi). Sanyo Press Co., Okayama, p. 161 - 167.

Lundqvist, U. and Lundqvist, A., 1988. Induced intermedium mutants in barley: origin morphology and inheritance. Hereditas 108: 13 - 26.

Nybom, N., 1954. Mutation types in barley. Acta Agriculturae Scandinavica IV:3: 430 - 456.

Persson, G., 1969. An attempt to find suitable genetic markers for dense ear loci in barley I. Hereditas 62: 25 - 96.

Persson, G. and Hagberg, A., 1969. Induced variation in a quantitative character in barley. Morphology and cytogenetics of erectoides mutants. Hereditas 61: 115 - 178.