International Database for Barley Genes and Barley Genetic Stocks
BGS 157, Brachytic 2, brh2
Stock number: BGS 157
Locus name: Brachytic 2
Locus symbol: brh2
Previous nomenclature and gene symbolization:
Brachytic 2 = br2 (12).
Breviaristatum-l = ari-l (7, 8).
Hordeum vulgare U-box E3 ubiquitin ligase = HvTUD1 (2).
Monofactorial recessive (11).
Located in chromosome 4HL (11); brh2.b is about 1.5 cM proximal from the glf3 (glossy leaf 3) locus (5, 11); brh2.b is over 22.8 cM proximal from the Kap1 (Hooded lemma 1) locus (11); brh2.b is near AFLP marker E4140-7 in subgroup 38-40 of the Proctor/Nudinka map (10), brh2.b is about 15.9 cM distal from SSR marker Bmag0353 near the boundary between 4H bins 06 and 07 (3); brh2.b is associated with SNP markers 2_0012 to 1_1319 (positions 57.19 to 110.93 cM) in 4H bins 05 to 07 of the Bowman backcross-derived line BW090 (4); ari-l.3 is associated with SNP markers 2_1374 to 2_1332 (positions 41.13 to 112.64 cM) in 4H bins 04 to 08 of the Bowman backcross-derived line BW050 (4),HvTUD1 is located at 550.51 Mb (59.89 cM) (2).
Plant height and vigor are reduced to about 2/3 normal; the awn is less than 1/4 normal length; the spike is semi-compact; and the leaf, kernel, glume and glume awn, rachilla, and coleoptile are shorter than in the original cultivar. Auricles are well developed and larger than those of the original cultivar (12). In the Bowman backcross-derived lines, the peduncle is about 1/2 normal length, kernel weights are slightly over 2/3 normal, yield is about 1/2 normal; however, rachis internode lengths are normal (3). The ari-l.3 allele at the brh2 locus is sensitive to gibberellic acid treatment (1). The Bowman backcross-derived for brh2.b, BW090, and ari-l.3, BW050, were morphologically similar to each other, shorter than Bowman, 65 vs. 90 cm. They also had short awns, 2.5 vs. 12 cm beyond the tip of the spike and small kernels. ComBW050 and BW090 have undulating leaf margins and more upright leaf blades than Bowman (2). Compared to Bowman, kernels were shorter, 7.5 vs. 9.8 mm, and thinner, 3.61 vs.3.83 mm, and weighed less, 40 vs. 56 mg. Grain yields for BW050 and BW090 were 1/2 to 2/3 of those produced by Bowman (6). The brh2 and ari-l mutants responded to exogenously applied brassinolide, which suggests an apparent brassinosteroid deficient phenotype (2). The brh2 locus is orthologous to TUD1 in rice (Oryza sativa L.), which encodes a U-box E3 ubiquitin ligase (2).
Origin of mutant:
An X-ray induced mutant in Svanhals (NGB 1482, PI 5474) (12).
brh2.b (Kmut 28, OUM283, GSHO 573) in Svanhals (NGB 1482, PI 5474) (11); ari-l.3 (NGB 115848, GSHO 1660) in Bonus (NGB14657, PI 189763) (8); ari-l.132 (NGB 115942) in Foma (NGB 14659, CIho 11333) (9); ari-l.135 (NGB 115945), -l.145 (NGB 115956), -l.214 (NGB 116023), -l.237 (NGB 116047) in Foma, -l.257 (NGB 116066) in Kristina (NGB 14661, NGB 1500) (8).
Mutant used for description and seed stocks:
brh2.b (GSHO 573) in Svanhals; ari-l.3 (GSHO 1660) in Bonus; brh2.b in Bowman (PI 483237, NGB 22812)*7 (GSHO 2016, BW090, NGB 20496); ari-l.3 in Bowman*7 (GSHO 2017, BW050, NGB 20458).
1. Börner, A. 1996. GA response in semidwarf barley. Barley Genet. Newsl. 25:24-26.
2. Braumann, I., W. Urban, A. Preuẞ, C. Dockter, S. Zakhrabekova, and M. Hansson. 2018. Semi-dwarf barley (Hordeum vulgare L.) brh2 and ari-l mutants are deficient in a U-box E3 ubiquitin ligase. Plant Growth Regul. 86:223-234.
3. Dahleen, L.S., L.J. Vander Wal, and J.D. Franckowiak. 2005. Characterization and molecular mapping of genes determining semidwarfism in barley. J. Hered. 96:654-662.
4. Druka, A., J. Franckowiak, U. Lundqvist, N. Bonar, J. Alexander, K. Houston, S. Radovic, F. Shahinnia, V. Vendramin, M. Morgante, N. Stein, and R. Waugh. 2011. Genetic dissection of barley morphology and development. Plant Physiol. 155:617-627.
5. Forster, B.P. 1993. Coordinator's report: Chromosome 4. Barley Genet. Newsl. 22:75-77.
6. Franckowiak, J.D. (Unpublished).
7. Franckowiak, J.D. 1995. The brachytic class of semidwarf mutants in barley. Barley Genet. Newsl. 24:56-59.
8. Kucera, J., U. Lundqvist, and Å. Gustafsson. 1975. Inheritance of breviaristatum mutants in barley. Hereditas 80:263-278.
9. Lundqvist, U. (Unpublished).
10. Pozzi, C., D. di Pietro, G. Halas, C. Roig, and F. Salamini. 2003. Integration of a barley (Hordeum vulgare) molecular linkage map with the position of genetic loci hosting 29 developmental mutants. Heredity 90:390-396.
11. Takahashi, R., J. Hayashi, and I. Moriya. 1971. Linkage studies in barley. Barley Genet. Newsl. 1:51-58.
12. Tsuchiya, T. 1962. Radiation breeding in two-rowed barley. Seiken Ziho 14:21-34.
T.E. Haus and T. Tsuchiya. 1971. Barley Genet. Newsl. 1:143.
T. Tsuchiya. 1980. Barley Genet. Newsl. 10:115.
J.D. Franckowiak and U. Lundqvist. 1997. Barley Genet. Newsl. 26:184.
J.D. Franckowiak and L.S. Dahleen. 2007. Barley Genet. Newsl. 37:235-236.
J.D. Franckowiak and U. Lundqvist. 2014. Barley Genet. Newsl. 44:95-96.
J.D. Franckowiak and U. Lundqvist. 2017. Barley Genet. Newsl. 47:84-85.
J.D. Franckowiak and U. Lundqvist. 2018. Barley Genet. Newsl. 48:91-92.