International Database for Barley Genes and Barley Genetic Stocks
BGS 455, Shrunken endosperm genetic 8, seg8
Stock number: BGS 455
Locus name: Shrunken endosperm genetic 8
Locus symbol: seg8
Previous nomenclature and gene symbolization:
Monofactorial recessive (6).
Located in chromosome 7H (7); seg8.k in a 4.6 cM interval flanked by markers GBM1516 and Bmag341 (9); seg8.k is associated with SNP markers 1_0772 to 1_0169 (positions 71.81 to 142.56 cM) in 7H bins 05 to 08 of the Bowman backcross-derived line BW840 (1) likely in 7H bin 07 at about 88 Mb.
Seed size is reduced and maturity is delayed. Seed weights of 24, 23, and 27% of normal are reported for plants grown in the field in Arizona, in the field in Montana, and in the greenhouse in Arizona, USA, respectively (8). Pollen mother cell meiosis and pollen fertility are normal. Seed from seg8.k plants can be used to establish stands under field conditions (7). Endosperms of seg8.k plants developed as two-filled lateral lobes with no central endosperm lobe, resulting in a distinct dorsal crease (2). This is evidence that the endosperm is divided into three lobes as explained by the phytomeric triad model (4). Kernels of the Bowman backcross-derived line for seg8.k, BW840, were very thin 3.01 vs. 3.84 mm in width and weighed much less, 1.7 vs. 5.6 mg, compared to those of Bowman. BW840 plants were similar to Bowman morphologically, but their grain yield was about 1/20 that of Bowman (3). The seg8.k mutant has defective endosperm development, reduced starch synthesis, and elevated monosaccharide concentrations, which resulted in higher early seed development-specific (ESD) β-amylase mRNA levels and enzyme activities in seg8.k compared to wild type (5).
Origin of mutant:
A spontaneous mutant in 60Ab1810-53 (CIho 15686) (8).
seg8.k (GSHO 2469) in 60Ab1810-53 (CIho 15686) (7, 8).
Mutant used for description and seed stocks:
seg8.k (GSHO 2469) in 60Ab1810-53; seg8.k in Bowman (PI 483237, NGB 22812)*3 (GSHO 1854); seg8.k in Bowman*5 (BW840, NGB 22277).
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. Felker, F.C., D.M. Peterson, and O.E. Nelson. 1985. Anatomy of immature grains of eight material effect shrunken endosperm barley mutants. Amer. J. Bot. 72:248-256.
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 Franckowiak, J.D. (Unpublished).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. Jung, W., R.W. Skadsen, and D.M. Peterson. 2001. Characterization of a novel barley β-amylase gene expressed only during early grain development. Seed Sci. Res. 11:325-333.
6. Ramage, R.T. 1983. Chromosome location of shrunken endosperm mutants seg6g and seg8k. Barley Genet. Newsl. 13:64-65.
7. Ramage, R.T., and C.L. Crandall. 1981. BGS 453, Shrunken endosperm, seg8. Barley Genet. Newsl. 11:103.
8. Ramage, R.T., and C.L. Crandall. 1981. Shrunken endosperm mutant seg8. Barley Genet. Newsl. 11:34.
9. Röder, M.S., C. Kaiser, and W. Weschke. 2006. Molecular mapping of the shrunken endosperm genes seg8 and sex1 in barley (Hordeum vulgare L.) Genome 49:1209-1214.
R.T. Ramage and C.L. Crandall. 1981. Barley Genet. Newsl. 11:103 as BGS 453.
R.T. Ramage. 1983. Barley Genet. Newsl. 13:116 as BGS 453.
T. Tsuchiya. 1983. Barley Genet. Newsl. 13:117. BGS number changed to BGS 455.
J.D. Franckowiak. 1997. Barley Genet. Newsl. 26:405.
J.D. Franckowiak. 2007. Barley Genet. Newsl. 37:272.
J.D. Franckowiak. 2013. Barley Genet. Newsl. 43:150-151.
J.D. Franckowiak. 2015. Barley Genet. Newsl. 45:170-171.
J.D. Franckowiak. 2018. Barley Genet. Newsl. 48:149-150.