International Database for Barley Genes and Barley Genetic Stocks
BGS 729, Dusky 2, dsk2
Stock number: BGS 729
Locus name: Dusky 2
Locus symbol: dsk2
Previous nomenclature and gene symbolization:
Male sterile genetic df = msg,,df (5).
Monofactorial recessive (5), but an additional recessive gene may be involved in expression (3, 4).
Location in chromosome 7HL (1); dsk2.b is associated with SNP markers1_0861 to 2_0365 (positions 183.90 to 229.66 cM) in 7H bins 11 to 13 of the Bowman backcross-derived line BW252 (1).
The original dsk2.b mutant was identified as a male sterile genetic mutant and assigned the temporary gene symbol msg,,df (3) (now converted to msg.df). Hockett reported deficiencies of mutant plants in segregating progenies of MSS354 for msg.df: 133 fertile to 15 male sterile in 1975 (3) and 222 to 18 in 1977 (4). When grown under greenhouse conditions, the mutant segregates were weak and developed severe necrotic lesions on the leaves shortly before heading (2). Plant vigor is a little better in Bowman backcross-derived line for dsk2.b, BW252, but mutant gene is still maintained in a heterozygous stock. The mutant plants in BW252 are very weak and self-fertile, but premature dying of the mutants limits seed production to very small kernels with poor viability. Spraying the fungicide Tilt on dsk2.b segregates of BW252 caused severe bleaching of leaf blades (2). The original stock, MSS354, may have contained two mutants: one associated with male sterility and a second for severe leaf necrosis.
Origin of mutant:
A spontaneous mutant in Betzes (PI 129430) isolated by R.F. Eslick (3).
dsk2.b (MSS 354) in Betzes (PI 129430) (3).
Mutant used for description and seed stocks:
dsk2.b (MSS 354) in Betzes; dsk2.b in Bowman (PI 483237)*5 (BW252, NGB 22077).
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 Franckowiak, J.D. (Unpublished).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. Hockett, E.A. 1975. Coordinator’s report: The genetic male sterile barley collection. Barley Genet. Newsl. 5:84-86.
4. Hockett, E.A. 1977. Reports from coordinator’s: The genetic male sterile barley collection . Barley Genet. Newsl. 7:97-100.
5. Hockett, E.A., and D.A. Reid. 1981. Spring and winter genetic male-sterile barley stocks. Crop Sci. 21:655-659.
J.D. Franckowiak. 2014. Barley Genet. Newsl. 44:208.