BGS 678, Breviaristatum-u, ari-u

The ari-u.245 mutant is an allele at the ert-t (Erectoides-t) or BRASSINOSTEROID-6-OXIDASE (HvBRD) locus, which encodes a barley brassinosteroid-6-oxidase (1). See BGS 566 for more information on the alleles at the ert-t or HvBRD locus.

Breviaristatum-245 = ari.245 (4).

Monofactorial recessive (4).
Located in chromosome 2HS (1,2); ari-u.245 is associated with SNP markers 2_0609 to 2_1377 (positions about 13.0 to 20.11 cM) from Foma in 2H bin 02 of the Bowman backcrossed-derived line BW031 (2), the ari-u.245 mutant is an allele at the ert-t or HvBRD locus, which encodes for a brassinosteroid-6-oxidase, and is located in the telomeric region of 2HS (1); in 2H bin 02.

Plants have reduced awn length, about 2/3 of normal with an undulated awn tip and an erect or brachytic growth habit (4). In the Bowman backcross-derived line for ari-u.245, BW031, a brachytic-like growth habit was observed, but expression of morphological traits was variable among nurseries with plant growth more reduced in moisture stressed nurseries. BW031 plants were 10 to 40% shorter and peduncles were 20 to 40% shorter compared to Bowman plants. Awn lengths of BW031 were 2/3 to 3/4 those for Bowman and rachis internode length varied from 2.9 to 4.3 mm compared to about 4.5 mm for Bowman. Kernels of BW031 were slightly smaller and 20% lighter. Grain yields varied from less than 1/3 to 3/4 of the Bowman yields (3). The variability in trait expression over environments observed in BW031 could be described as phenotypic plasticity, see Lacaze et al. (5). The ari-u.245 mutant in BW031 plants exhibited the brassinosteroid-deficient phenotype: shorter rachis internode length, short awns, acute leaf angles, slightly undulating basal leaf blade margins, and a slightly elongated basal rachis internode (1).

An N-methyl-N-nitrosourea induced mutant in Foma (NGB 14659, CIho 11333) (4, 6).

ari-u.245 (NGB 116055) in Foma (NGB 14659, CIho 11333) (4, 6); ari-u.304 (previously named ari-o.304) (NGB 116129) in Kristina (NGB 14661, NGB 1500) (1. 6).

ari-u.245 (NGB 116055) in Foma; ari-u.245 via ND14701 in Bowman (PI 483237)*5 (BW031, NGB 20439).

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. Hanson. 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. Vendramin, M. Morgante, N. Stein, and R. Waugh. 2011. Genetic dissection of barley morphology and development. Plant Physiol. 155:617-627.

3. Franckowiak, J.D. (Unpublished).

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

5. Lacaze, X., P. M. Hayes, and A. Korol. 2009. Genetics of phenotypic plasticity: QTL analysis in barley, Hordeum vulgare. Heredity 102:163-173.

6. Lundqvist, U. (Unpublished).

J.D. Franckowiak and U. Lundqvist. 2011. Barley Genet. Newsl. 41:200.

U. Lundqvist and J.D. Franckowiak. 2015. Barley Genet. Newsl. 45:239-240.