BGS 741, Stubble 1, stb1

Gillette (2, 4).
Stubble = stb (3, 4).
Short rachilla hair 2 = srh2 (1).

Monofactorial recessive (3, 4).
Location is unknown; stb1.a is associated with several groups of retained SNP markers in 1H (positions 61.55 to 157.02 cM in bins 06 to 12), 3H (52.41 to 119.10 cM in bins 04 to 07), and 5H (26.06 to 98.42 cM in bins 02 to 10) in the Bowman backcross-derived line BW874 (1).

Gillette or stubble 1, stb1.a, is expressed on the rachilla, glume, and rachis margin hairs. The effect looks as if a mower had been run over these areas leaving a “stubble” of very short hairs. This expression can readily be seen in both lines with long rachilla hair (Srh1) and short rachilla hair (srh1) (3, 4). The stubble trait cannot be scored easily in certain smooth-awned barleys where most, and sometimes all, hairs on the glumes and rachis margins are missing. In an F2 population, segregation of the stubble trait appeared independent of the short rachilla hair trait (4). The stubble trait was found in the world collection barleys from Korea and adjacent China (4). Isogenic lines with "stubble" (stb1) and short rachilla hair 1 (srh1) were selected from a Manchuria (CIho 2330) X Gillette (CIho 4485) cross (4). Both parents have rough awns (Raw1 plus Raw2).

Natural occurrence in US 85 [GSHO 656, selected from CIho 4551 (PI 69686) introduced from Jilin, China] and US 86 [GSHO 659, selected from CIho 4485 (PI 69621) from Shanxi, China] (2, 4).

stb1.a in GSHO 659 (T12-34) selected from CIho 4485 (PI 69621) (2).

stb1.a in GSHO 656 and GSHO 659; stb1.a from GSHO 656 in Bowman (PI 483237)*2 (BW874, NGB 22308). The isogenic lines for stb1.a were selected in the F25 generation from a Manchuria (CIho 2330) X Gillette (CIho 4485) cross: CIho 16005 (Srh1 Stb1), CIho 16006 (Srh1 stb1.a), CIho 16007 (srh1.a Stb1), and CIho srh1.a stb1.a).

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. Hang, A. 1995. List of genetic stocks in barley arranged in numerical order of BGS (Barley Genetic Stock) numbers. USDA-ARS National Small Grains Germplasm Research Facility, Aberdeen, ID 83210. (Notes from T. Tsuchiya on the collection of barley genetic stocks at Colorado State University.)
3. Reid, D.A., and G.A. Wiebe. 1968. Taxonomy, botany, classification, and world collection. p. 61-84. In Barley: Origin, Botany, Culture, Winterhardiness, Genetics, Utilization, Pests. USDA Agric. Handb. No. 338.
4. Wiebe, G.A. 1972. “Stubble” gene. Barley Genet. Newsl. 2:109.

J.D. Franckowiak 2017. Barley Genet. Newsl. 47:183-184.