International Database for Barley Genes and Barley Genetic Stocks

BGS 133, Semidwarf 2, sdw2

BGN  45:108
Stock number: BGS 133
Locus name: Semidwarf 2
Locus symbol: sdw2

Previous nomenclature and gene symbolization:

Semidwarf-b = sdw-b (3).


Monofactorial recessive (3).
Located in chromosome 3HL (3); sdw2.b is over 34.5 cM distal from the sld1 (slender dwarf 1) locus (3). sdw2.b is associated with SNP markers 2_0650 to 2_0612 (positions 192.0 to 198.33 cM) in 3H bins 12 to 13 of the Bowman backcross-derived line BW829 (1).


Plants are about 3/4 normal height; culms are thin with narrow, short, erect leaves. The flag leaf is narrow and short. The peduncle is short, the collar has a small leaf-like bract, and the basal rachis internode is elongated (3). Compared to Bowman, plants of the Bowman backcross-derived line for sdw2.b, BW829, were shorter 10 to 20% shorter, peduncles were 1/2 to 2/3 as long, rachis internodes were 10 to 20% shorter, and leaf blades were about 2/3 normal length and width. BW829 plants headed 1 to 3 days earlier than Bowman and they yielded about 2/3 as much. Kernels were shorter and thinner and weighed about 20% less, 4.6 vs 5.6 mg (2).

Origin of mutant:

A N-methyl-N-nitrosourea induced mutant in Mg4170 (3).

Mutational events:

sdw2.b (267MK, later called 437MK, GSHO 2466) in Mg4170 (3).

Mutant used for description and seed stocks:

sdw2.b (GSHO 2466) in Mg4170; sdw2.b in Bowman (PI 483237)*7 (GSHO 1965, BW829, NGB 22266).


1. 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.

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 Franckowiak, J.D. (Unpublished).

3. Szarejko, I., and M. Maluszynski. 1984. Two new dwarfism genes on barley chromosome 3. Barley Genet. Newsl. 14:35-38.


J.D. Franckowiak. 1997. Barley Genet. Newsl. 26:169.


J.D. Franckowiak. 1997. Barley Genet. Newsl. 45:108.