International Database for Barley Genes and Barley Genetic Stocks

BGS 620, Calcaroides-b, cal-b

BGN  44:197
Stock number: BGS 620
Locus name: Calcaroides-b
Locus symbol: cal-b

Previous nomenclature and gene symbolization:



Monofactorial recessive (5, 6).
Located in chromosome 5HL (7); cal-b.2 is about 4.2 cM proximal from AFLP marker E4040-4 and probably near molecular marker CDO749 in 5H bin 04 (7); cal-b.2 is associated with SNP markers 1_1198 to 2_0713 (positions 73.70 to 101.69 cM) in 5H bins 04 to 06 of the Bowman backcrossed-derived line BW104 (2), likely in 5H bin 05.


At the tip of the lemma proper, in a position corresponding to the transition between lemma and awn, cal-b mutants have a knee-like ectopic structure (1, 7). In mutant cal-b.2, frequently only an enlargement of the basal third of the awn is evident and the enlargement is expressed more in terminal and subterminal spikelets. Leaf knots and leaf curling occurs also (7). The awn malformation of the cal-b.2 mutant is associated with developmental activation of the phytomeric triad separating the lemma from awn (4). In the Bowman backcross-derived line for cal-b.2, BW104, plants were slightly shorter and spikes had a more lax arrangement of spikelets (3). The awns of BW104 were slightly shorter, 10 vs. 12 cm, than those of Bowman. Leaf blades were 1/2 to 2/3 as wide, and the spikes had about 5 fewer rachis internodes with fertile spikelets than those of Bowman. Kernels were shorter and thinner and weighed about 20% less. Grain yields of BW104 were about 1/3 of normal (3).

Origin of mutant:

An X-ray induced mutant in Bonus (PI 189763, NGB14657) (5, 6).

Mutational events:

cal-b.2 (NGB 114282, GSHO 1697), cal-b.19 (NGB 114298) in Bonus (NGB14657, PI 189763) (6).

Mutant used for description and seed stocks:

cal-b.2 (NGB 114282, GSHO 1697) in Bonus; cal-b.2 in Bowman (PI 483237)*4 (GSHO 2187, BW104, NGB 20510).


1. Bossinger, G., U. Lundqvist, W. Rohde, and F. Salamini. 1992. Genetics of plant development in barley. p. 989-1017. In L. Munck, K. Kirkegaard, and B. Jensen (eds.). Barley Genetics VI. Proc. Sixth Int. Barley Genet. Symp., Helsingborg, 1991. Munksgaard Int. Publ., Copenhagen.

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 Franckowiak, J.D. (Unpublished).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. Franckowiak, J.D., B.P. Forster, U. Lundqvist, J. Lyon, I. Pitkethly, and W.T.B. Thomas. 2010. Developmental mutants as a guide to the barley phytomer. pp. 46-60. In: S. Ceccarelli and S. Grando (eds), Proc. 10th International Barley Genetics Symposium, 5-10 April 2008, Alexandria Egypt. ICARDA, PO Box 5466, Aleppo, Syria.

5. 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.

6. Lundqvist, U. 1993 Coordinator's report: Ear morphology genes. Barley Genet. Newsl. 22:137-139.

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.


U. Lundqvist and J. D. Franckowiak. 2002. Barley Genet. Newsl. 32:121.


U. Lundqvist and J.D. Franckowiak. 2014. Barley Genet. Newsl. 44:197-198.