International Database for Barley Genes and Barley Genetic Stocks

BGS 75, Awnless 1, Lks1

BGN  41:84
Stock number: BGS 75
Locus name: Awnless 1
Locus symbol: Lks1

Previous nomenclature and gene symbolization:

Awnless = I (Ikeno, see 3).
Awnless = Lk (4).
Awnless = S (8).
Two-rowed awnless = Vlk (12).


Monofactorial dominant (3, 4, 7).
Located in chromosome 2HL (3, 4); Lks1.a is about 9.6 cM distal from the vrs1 (six-rowed spike 1) locus (8); Lks1.a is associated with SNP markers 1_0619 to 1_1533 (positions 133.59 to 141.56 cM) in 2H bins 09 to 10 of the Bowman backcross-derived line BW490 (2); Lks1.b is associated with SNP markers 2_0667 to 1_0287 (positions 117.73 to 138.37 cM) in 7H bins 08 to 09 of the Bowman backcross-derived line BW491 (2), likely in 2H bin 09.


Little or no development of the appendage on the lemma occurs. Heterozygotes may be awnless (1) or awnletted (4) depending upon the source stock for the Lks1 gene and the genetic background. The Lks1.a allele in Engleawnless will not recombine with alleles at the vrs1 (six-rowed spike 1) locus (4, 13) because a short paracentric inversion is present in Engleawnless (14). The complex vrs1 locus may include awnless and reduced awn length mutants (13). However, the Lks1.b gene in CIho 13311 does recombine with vrs1 locus and is associated with a dominant instead of a recessive allele at the Gth (toothed lemma) locus (5). In the Atlas near-isogenic lines, the awnless trait reduced kernel weight by about 15% (9, 11) and grain yield by about 10% (9, 10, 11). Both backcross-derived lines, BW490 with Lks1.a and BW491 with Lks1.b, are slightly taller than Bowman. The kernels of BW490 are longer and thinner than those of Bowman and weighed about 25% less. The kernels of BW491 are similar in size to those of Bowman and weighed 5 to 10% less (5).

Origin of mutant:

Natural occurrence in Engleawnless or Hordeum inerme (CIho 2505, PI 174480) (3, 4); and several other accessions (4, 8).

Mutational events:

Lks1.a in Engleawnless (CIho 2505, GSHO 44) from England (1, 12, 14); Lks1.b in CIho 13311 (PI 316871, GSHO 1579) from Ethiopia; the dissimilar SNP marker haplotypes in the critical region of 2H suggests that the Lks1 variants are of independent origin (2).

Mutant used for description and seed stocks:

Lks1.a in Engleawnless (GSHO 44); Lks1.b in CIho 13311 (PI 316871, GSHO 1579); Lks1.a from CIho 2505 in Betzes (PI 129430)*7 (PI 534510); Lks1.a in Compana (PI 537442)*7 (PI 534512); Lks1.a in Dekap (CIho 3351)*7 (PI 534514); Lks1.a in Ingrid (NGB 2671, CIho 10083)*7 (PI 534516, Ridawn) (4); Lks1.a from Ridawn in Bowman (PI 483237)*5 (GSHO 1913); Lks1.a in Bowman*6 (BW490, NGB 20718); Lks1.b from CIho 13311 in Bowman*6 (GSHO 1912); Lks1.b in Bowman*7 (BW491, NGB 20719).


1. Austenson, H.M. 1948. Linkage relations of the male sterile gene ms2 in barley. M.S. Thesis. Univ. of Saskatchewan, Saskatoon.
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. Engledow, F.L. 1921. Inheritance in barley. II. The awn and the lateral floret. J. Agric. Sci. 11:159-196.
4. Engledow, F.L. 1924. Inheritance in barley. III. The awn and the lateral floret (cont'd): fluctuation: a linkage: multiple allelomorphs. J. Genet. 14:49-87.
5. Franckowiak, J.D. (Unpublished).
6. Hockett, E.A., and H.F. Bowman. 1990. Registration of awnless (short-awned) barley isogenic lines. Crop Sci. 30:754.
7. Huber, J.A. 1931. Vererbungsstudien an Gerstenkreuzungen. II. Zur Genetik der Gerstenähre. Z. Zücht. A. Pflanzenzücht. 16:394-464.
8. Kuckuck, H. 1930. Versuche einer vorläufigen Chromosomentopographie bei Gerste. Züchter 2:68-72.
9. Qualset, C.O., C.W. Schaller, and J.C. Wiloliams. 1965. Performance of isogenic lines of barley as influenced by awn length, linkage blocks, and environment. Crop Sci. 5:489-494.
10. Schaller, C.W., C.O. Qualset, and N. J. Rutger. 1972. Isogenic analysis of the effects of the awn on productivity of barley. Crop Science 12:531-535.
11. Schaller, C.W., and C.O. Qualset. 1975. Isogenic analysis of productivity in barley: Interaction of genes affecting awn length and leaf-spotting. Crop. Sci. 15:378-382.

12. Takahashi, R., J. Hayashi, I. Moriya, and S. Yasuda. 1982. Studies on classification and inheritance of barley varieties having awnless or short-awned lateral spikelets (Bozu barley). I. Variation of awn types and classification. Nogaku Kenyu 60:13-24. [In Japanese with English summary.]
13. Tsuchiya, T., and R.J. Singh. 1972. Another case of paracentric inversion in a genetic stock, Engleawnless. Barley Genet. Newsl. 2:110-111.
14. Wiebe, G.A. 1972. Tight linkage of the awnless gene in Engleawnless with the Vv locus. Barley Genet. Newsl. 2:108.


J.D. Franckowiak. 1997. Barley Genet. Newsl. 26:112.


J.D. Franckowiak. 2011. Barley Genet. Newsl. 41:84-85.