International Database for Barley Genes and Barley Genetic Stocks

BGS 62, Subjacent hood 1, sbk1

BGN  48:75
Stock number: BGS 62
Locus name: Subjacent hood 1
Locus symbol: sbk1

Previous nomenclature and gene symbolization:

Subjacent hood = sk (9).
Hooded awn 2 = k2 (12).
Hoods = kr (11).
Calcaroides-a = cal-a (4, 5).


Monofactorial recessive (8, 9).
Located in chromosome 2HS (8, 9, 10); cal-a.1 is distal from AFLP marker E3733-7 and RFLP marker CDO57 (7); sbk1.b is associated with SNP markers 1_0326 and 1_1059 (positions 16.91 and 17.96 cM) in 2H bin 02 of the Bowman backcross-derived line BW767; sbk1.a is associated with SNP markers 1_1059 to 2_0563 (positions 17.96 to 21.19 cM) in 2H bin 02 of the Bowman backcross-derived line BW766; cal-a.1 is associated with SNP marker 1_0326 (position 16.91 cM) in 2H bin 02 of the Bowman backcross-derived line BW103 (2).


Unlike the Kap1 (Hooded lemma 1) mutants, the lemma appendage, or its modification is situated somewhat below the top of the lemma. Lemma modifications may include a central cup-like cavity or sac in some alleles and/or pronounced lemma wings in other alleles (1, 7). The modified lemma bears a short distal awn. Only a few florets of the spike have malformations in alleles (cal-a.3, -a.6, -a.7, and -a.17), and these alleles are associated with the formation of pronounced wings (7). There are no rudiments of a floral organ within the hood-like cavity (7, 8, 9). Leaf blade knots and leaf curling are present in some alleles (7). In the homozygous condition, the sbk1.a gene is epistatic to the Kap1.a (Hooded lemma 1) and to Lks1.a (Awnless 1) genes (8). Plants of the Bowman backcross-derived lines for cal1,a (BW103, sbk1.a (BW766), and sbk1.b (BW767) were much less vigorous than Bowman, about 3/4 of normal height and 3 to 4 fewer fertile rachis nodes. The kernel of the BW766 and BW767 plants were about 1/2 of normal weight, and grain yields were about 1/10 of normal. Plants of the BW103 line were more vigorous with kernel weights about 3/4 of those for Bowman and grain yield of about 1/2 of normal. The effects of the sbk1 mutants on plant vigor were less pronounced in cooler environments (3).

Origin of mutant:

A spontaneous mutant identified as Tayeh 13 (OUC335, GSHO 267) (6); an X-ray induced mutant in Bonus (NGB 14657, PI 189763) (6).

Mutational events:

sbk1.a (OUC335, GSHO 267) in Tayeh 13 (8); cal-a.1 (NGB 114280, 114281) in Bonus (NGB 14657, PI 189763) (5, 6); cal-a.3 (NGB 114283), -a.5 (NGB 114285) in Foma (NGB 14659, CIho 11333); cal-a.6 (NGB 114286) in Bonus; cal-a.7 (NGB 114287), -a.8 (NGB 114288), -a.11 (NGB 114291), -a.12 (NGB 114292), -a.13 (NGB 114293) in Foma; cal-a.16 (NGB 114295), -a.17 (NGB 114296), -a.20 (NGB 114299), -a.21 (NGB 114300) in Bonus (5, 6); sbk1.b (kr) in Montcalm (CIho 7149) (11).

Mutant used for description and seed stocks:

sbk1.a (GSHO 267) in Tayeh 13; sbk1.a via R.I. Wolfe’s Multiple Recessive Stock for chromosome 2 in Bowman (PI 483237, NGB 22812)*4 (BW766, NGB 22234); sbk1.b in Montcalm; sbk1.b from Montcalm in Bowman*7 (GSHO 1874, BW767, NGB 22235); cal-a.1 (GSHO 286, NGB 114280, NGB 114281) in Bonus; cal-a.1 from Bonus in Bowman*3 (GSHO 2186); cal-a.1 in Bowman*6 (BW103, NGB 20509).


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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. 2010. Genetic dissection of barley morphology and development. Plant Physiology 155:617-627.
3. Franckowiak, J.D. (Unpublished).
4. Gustafsson, Å., A. Hagberg, U. Lundqvist, and G. Persson. 1969. A proposed system of symbols for the collection of barley mutants at Svalöv. Hereditas 62:409-414.
5. Lundqvist, U. 1993. Coordinator's report: Ear morphology genes. Barley Genet. Newsl. 22:137-139.
6. Lundqvist, U. (Unpublished).
7. Pozzi, C., P. Faccioli, V. Terzi, A.M. Stanca, S. Cerioli, P. Castiglioni, R. Fink, R. Capone, K.J. Müller, G. Bossinger, W. Rohde, and F. Salamini. 2000. Genetics of mutations affecting the development of a barley floral bract. Genetics 154:1335-1346.
8. Takahashi, R., and J. Hayashi. 1966. Inheritance and linkage studies in barley. II. Assignment of several new mutant genes to their respective linkage groups by the trisomic method of analysis. Ber. Ohara Inst. landw. Biol., Okayama Univ. 13:185-198.
9. Takahashi, R., J. Yamamoto, S. Yasuda, and Y. Itano. 1953. Inheritance and linkage studies in barley. Ber. Ohara Inst. landw. Forsch. 10:29-52.
10. Tsuchiya, T., and R.J. Singh. 1973. Further information on telotrisomic analysis in barley. Barley Genet. Newsl. 3:75-79.
11. Walker, G.W.R., J. Dietrich, R. Miller, and K.J. Kasha. 1963. Recent barley mutants and their linkages II. Genetic data for further mutants. Can. J. Genet. Cytol. 5:200-219.
12. Woodward, R.W. 1957. Linkages in barley. Agron. J. 49:92-94.


T. Tsuchiya and T.E. Haus. 1971. Barley Genet. Newsl. 1:122.


J.D. Franckowiak and U. Lundqvist. 1997. Barley Genet. Newsl. 26:98.
J.D. Franckowiak and U. Lundqvist. 2002. Barley Genet. Newsl. 32:83-84.
J.D. Franckowiak and U. Lundqvist. 2010. Barley Genet. Newsl. 40:51-52.
U. Lundqvist and J.D. Franckowiak. 2018. Barley Genet. Newsl. 48:75-76.