International Database for Barley Genes and Barley Genetic Stocks

BGS 119, Desynapsis 2, des2

BGN  43:84
Stock number: BGS 119
Locus name: Desynapsis 2
Locus symbol: des2

Previous nomenclature and gene symbolization:

Desynaptic chromosomes = ds (2, 3).


Monofactorial recessive (2, 3).
Located in chromosome 3H (2, 3); des2.b is associated with SNP markers 1_0825 to 1_0312 (positions 61.77 to 173.82 cM) in 3H bins 05 to 11 of the Bowman backcross-derived line BW238 (1);


Synapsed homologous chromosomes disjoin precociously because of an apparent lack of chiasmata (2). The chromosomes are paired during pachytene and undergo desynapsis during diplotene. The degree of desynapsis is d = 6.0  3.3 with a range from 7 ring bivalents (d = 0) to 2 rod bivalents plus 10 univalents (d = 12). Lagging chromosomes and micronuclei are observed frequently at telophase I. Microspore tetrads contain an average of 1.8 micronuclei per tetrad and a range of 0 to 7. Ovule fertility is about 1% and highly variable from spike to spike on the same plant (5). The very low fertility trait occurs infrequently in the F2 progeny from the cross to Bowman, but nearly 1/4 the plants show reduced seed set (about 60%) (4). Grain yields of the Bowman backcross-derived line for des2.b, BW238, varied from less than 10% to nearly 1/2 those of Bowman. BW238 and Bowman were similar for other morphological traits, except kernels weighed slightly more (4).

Origin of mutant:

An X-ray induced mutant in Husky (CIho 9537) (2).

Mutational events:

des2.b (GSHO 593) in Husky (CIho 9537) (2, 6).

Mutant used for description and seed stocks:

des2.b (GSHO 593) in Husky; des2.b in Bowman (PI 483237)*5 (BW238, NGB 22065).


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. Enns, H., and E.N. Larter. 1960. Note on the inheritance of ds; a gene governing meiotic chromosome behaviour in barley. Can. J. Plant Sci. 40:570-571.
3. Enns, H., and E.N. Larter. 1962. Linkage relations of ds: A gene governing chromosome behaviour in barley. Can. J. Genet. Cytol. 4:263-266.
4. Franckowiak, J.D. (Unpublished).
5. Hernandez-Soriano, J.M. 1973. Desynaptic mutants in Betzes barley. M.S. Thesis. Univ. of Arizona, Tucson.
6. Ramage, R.T., and J.M. Hernandez-Soriano. 1972. Desynaptic genes in barley. Barley Genet. Newsl. 2:65-68.


J.M. Hernandez-Soriano, R.T. Ramage, and R.F. Eslick. 1973. Barley Genet. Newsl. 3:125.


J.D. Franckowiak. 1997. Barley Genet. Newsl. 26:154.
J.D. Franckowiak. 2013. Barley Genet. Newsl. 43:84-85.