International Database for Barley Genes and Barley Genetic Stocks

BGS 241, Accordion rachis 3, Acr3

BGN  48:115
Stock number: BGS 241
Locus name: Accordion rachis 3
Locus symbol: Acr3

Previous nomenclature and gene symbolization:

Lax spike = Lax (7, 8)
Accordion rachis = acr (6).
Accordion rachis c = acr.c (4).
Accordion rachis 1 = acr1.a (5).


Monofactorial incomplete dominant for lax spike, the third factor required for expression of accordion rachis 1 (acr1) trait (3, 4).
Located in chromosome 1HL (3); Acr3.a is associated with SNP markers 2_1357 to 2_0997 (positions 76.96 to 94.86 cM) in 1HL of the Bowman backcross-derived lines BW009 and BW439 (3), likely in 1H bin 08. Bowman backcross-derived lines with Acr3.b3, BW007, BW009 with Acr3.a3, BW438 with Acr3.a and BW456 with Acr3.am3 contain overlapping segments of variable length and SNP marker patterns in 1H from their donor parents (3).


Mutant plants have slightly elongated rachis internodes (1). The Acr3 gene is in the third chromosomal region associated with expression of the accordion rachis trait in Bowman backcross derived lines BW009 and BW439. The contribution of the 1HL region to characteristics of the accordion phenotype is unknown. Only the line BW438 ( or has a 1HL donor chromosome segment in a line lacking both the 2H and 4HL segments identified as containing the acr1 (see BGS 097) and Acr2 (see BGS 189) genes, respectively. Plants of the Bowman derived line BW438 ranged from slightly shorter to slightly taller than Bowman and had slightly longer rachis internodes (4). Kernels of BW438 were slightly longer than those of Bowman, but weighed slightly less (5.3 vs. 6.0 mg). Grain yields of BW009 were about 2/3 that of Bowman (4).

Origin of mutant:

A naturally occurring deviant for lax spike from several sources (3, 4).

Mutational events:

Acr3.a3 in ACBV89B229 (GSHO 1617) and ACBV89B232 (GSHO 1573) (3, 9); Acr3.b3 in Burma Girl (CIho 14831, GSHO 1071) (4, 9); Acr2.am2 and in AB 1398 [GSHO 1115, likely CIho 14785 from G.A. Wiebe (1)]. Acr3.c3 in T188 (GSHO 1480) from R.W. Woodward (2).

Mutant used for description and seed stocks:

Acr3.a3 in ACBV89B229 (GSHO 1617); Acr3.b3 in Burma Girl (GSHO 1071); Acr2.am2 and in AB 1398 (CIho 14785); from AB 1398 in Bowman*5 (BW438, NGB 20670); Acr3.b3 from Burma Girl in Bowman *2 (GSHO 1898); Acr3.b3 in Bowman*5 (BW007, NGB 20415); Acr32.am3 from AB 1398 in Bowman*4 (BW456, NGB 20688); Acr3.a3 plus acr1.a and Acr2.a2 in Bowman*7 (BW009, NGB 20417 and BW439, NGB 20671); Acr3.c3 in T188 (GSHO 1480); Acr3.c3 from T188 in Bowman*6 (BW008, NGB 20416).


1. Bockelman, H. (​http:​/​​/​​/​cgi-bin​/​npgs​/​acc​/​​).
2. Doney, D.L. 1961. An inheritance and linkage study of barley with special emphasis on purple pigmentation of the auricle. M.S. Thesis. Utah State Univ., Logan.
3 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. 2010. Genetic Dissection of barley morphology and development. Plant Physiology. Epubl. 2010 November 18, 2010 as DOI:10.1104/pp110.166249.
4. Franckowiak, J.D. (Unpublished).
5. Franckowiak J.D. 2001. BGS 97, Accordion rachis 1, acr1. Barley Genet. Newsl. 32:85.
6. Haus, T.E. 1957. Inheritance of rachis internode length and an abnormal rachis type in barley. Dissertation Abstr. 49:179-180.
7. Nilan, R.A. 1964. The cytology and genetics of barley, 1951-1962. Monogr. Suppl. 3, Res. Stud. Vol. 32, No. 1. Washington State Univ. Press, Pullman.
8. Smith, L. 1951. Cytology and genetics of barley. Bot. Rev. 17:1-55, 133-202, 285-355.
9. Wolfe, R.I. 1990. (Personal communications).


J.D. Franckowiak. 2010. Barley Genet. Newsl. 40:85-86.


J.D. Franckowiak. 2017. Barley Genet. Newsl. 47:105-106.
J.D. Franckowiak. 2018. Barley Genet. Newsl. 48:115-116.