BGS 92, Erectoides-u, ert-u

The ert-u.56 mutant is one of the alleles at the ari-o (Breviaristatum-o) locus (1). Other alleles at previously named loci include ert-zd.159 (Erectoides-zd, BGS 93), brh14.q (Brachytic 14, BGS 148), and brh16.v (Brachytic 16, BGS 44) (1). See BGS 556 for more information on the alleles at the ari-o locus.

Erectoides-56 = ert-56 (6).
Brachytic 5 = br5 (10).

Monofactorial recessive (6).
Located in chromosome 7Hl (1, 2); ert-u.56 is associated with SNP marker 1_0547 (about position 228 cM) in 7H bin 13 of the Bowman backcross-derived line BW325 (2); ert-u.56 is an allele at the HvDIM locus located in chromosome 7H at position 138.2 cm (1) in the barley genome map (9). The ert-u.56 mutant was previously associated with chromosome 2H based on linkage drag with the Gth1 (Toothed lemma 1) locus (4).

Spikes are slightly denser than those of the parent with a rachis internode length estimate of 2.7 mm, and culms are about 3/4 normal length (7). Plants have a brachytic-like pattern of growth (3, 10). Spike density is decreased by GA3 treatment of plants as the flag leaf emerges (8).Compared to Bowman, plants of the Bowman backcross-derived line for ert-u.56, BW325, were 10 to 20% shorter; and had shorter peduncles, approximately 23 vs. 31 cm and shorter awns, 8 vs. 11 cm beyond the tip of the last spikelet. Rachis internodes of BW325 averaged 4.1 vs. 4.6 mm for Bowman. Also, leaf blades and kernels were slightly shorter. The kernel weights for BW325 were nearly equal to those of Bowman, but grain yields were 25 to 50% lower (5). As with other mutants at the ari-o locus, ert-u.56 shows a brassinosteroid-deficient phenotype that includes a short culm, about 70% of normal, caused largely by an extreme shortening of the second culm internode (1). Other common traits include shorter rachis internodes, short awns, acute leaf angles, slightly undulating leaf margins, and a slightly elongated basal rachis internode (1). The six Bowman backcross-derived lines with a mutation at the ari-o or HvDIM locus, ari-o.40, brh14.af, brh14.q, brh16.v, ert-u.56, and ert-zd.159, have retained a small, common genetic donor parent interval (1). The sequence of HvDIM, encoding the barley Δ5-sterol-Δ24-reductase DIMINUTO, corresponds directly to single-nucleotide polymorphism (SNP) marker 1_0547 located in the telomere on the long arm of chromosome 7H (1).

An X-ray induced mutant in Bonus (NGB 14657, PI 189763) (6).

ert-u.56 (NGB 112655, GSHO 496) in Bonus (NGB 14657, PI 189763) (6).

ert-u.56 (NGB 112655, GSHO 496); in Bonus; ert-u.56 in Bowman (PI 483237)*8 (GSHO 1904, BW325, NGB 22120).

1. Dockter, C., D. Gruszka, I, Braumann, A. Druka, I. Druka, J. Franckowiak, S.P. Gough, A. Janeczko, M. Kurowska, J. Lundqvist, U. Lundqvist, M. Marzec, I. Matyszczak, A.H. Müller, J. Oklestkova, B. Schulz, S, Zakhrabekova, and M. Hansson. 2014. Induced variations in brassinosteroid genes define barley height and sturdiness, and expand the green revolution genetic toolkit. Plant Physiol. 166:1912-1927.
2. Druka, A., J. Franckowiak, U. Lundqvist, N. Bonar, J. Alexander, K. Houston, S. Radovic, F. Shahinnia, V. Vendrarnin, M. Morgante, N. Stein, and R. Waugh. 2011. Genetic dissection of barley morphology and development. Plant Physiol. 155:617-627.
3. Franckowiak, J.D. 1995. The brachytic class of semidwarf mutants in barley. Barley Genet. Newsl. 24:56-59.
4. Franckowiak, J.D. 1995. Notes on linkage drag in Bowman backcross derived lines of spring barley. Barley Genet. Newsl. 24:63-70.
5. Franckowiak, J.D. (Unpublished).
6. Hagberg, A., Å. Gustafsson, and L. Ehrenberg. 1958. Sparsely contra densely ionizing radiations and the origin of erectoid mutants in barley. Hereditas 44:523-530.
7. Persson, G., and A. Hagberg. 1969. Induced variation in a quantitative character in barley. Morphology and cytogenetics of erectoides mutants. Hereditas 61:115-178.
8. Stoy, V., and A. Hagberg. 1967. Effects of growth regulators on ear density mutants in barley. Hereditas 58:359-384.
9. The International Barley Genome Sequencing Consortium. 2012. A physical, genetic and functional sequence assembly of the barley genome. Nature 491:711-716.
10. Tsuchiya, T. 1976. Allelism testing of genes between brachytic and erectoides mutants. Barley Genet. Newsl. 6:79-81.

U. Lundqvist and J.D. Franckowiak. 1997. Barley Genet. Newsl. 26:131.

U. Lundqvist and J.D. Franckowiak. 1997. Barley Genet. Newsl. 45.100-101.