International Database for Barley Genes and Barley Genetic Stocks

BGS 546, Intermedium spike-k, int-k

BGN  44:180
Stock number: BGS 546
Locus name: Intermedium spike-k
Locus symbol: int-k

Previous nomenclature and gene symbolization:



Monofactorial recessive (4).
Located in chromosome 7H (1); int-k.47 is in the centromeric region closely linked to markers Bmag0217 and Bmac0162 in 7H bins 06 to 07 (1); int-k.47 is associated with SNP markers 1_0721 to 2_0485 (positions 82.82 to 121.90 cM) in 7H bins 06 to 07 of the Bowman backcrossed-derived line BW427 (2).


The spike is short and dense in the original mutant. Lateral spikelets are enlarged and the apex is pointed, and they occasionally have short awns. Seed set does not occur in lateral spikelets and the central spikelets are semi-sterile (4). Plants of the original stock have a dense coating of surface waxes (3). In the Bowman backcross-derived line for int-k.47, BW427, plants appeared small and weak (about 3/4 normal height) and had short spikes (2 to 6 fewer spikelets), reduced awn length (4 vs. 12 cm), and very poor seed set. Awns of BW427 plants are semi-rough, but F1 hybrids with Bowman have semi-smooth awns (3). BW427 plants headed 1 to 2 days earlier than Bowman. The flag minus one leaf blades were shorter (14 vs. 19 cm) and narrower (0.6 vs. 0.8 cm) and had less surface area (84 vs. 152 cm2). BW427 kernels were short (8.6 vs. 9.4 mm) and narrow (3.3 vs. 3.8 mm) and weighed less (36 vs. 58 mg). Grain yields for BW427 were 1/4 to 1/3 of those for Bowman (3).

Origin of mutant:

An ethyl methanesulfonate induced mutant in Kristina (NGB14661, NGB 1500) (4).

Mutational events:

int-k.47 (NGB 115465, GSHO 1770) in Kristina (NGB14661, NGB 1500) (4).

Mutant used for description and seed stocks:

int-k.47 (GSHO 1770, NGB 115465) in Kristina; int-k.47 in Bowman (PI 483237)*7 (BW427, NGB 20660).


1. Dahleen, L.S., and J.D. Franckowiak. 2006. SSR Linkages to eight additional morphological marker traits. Barley Genet. Newsl. 36:12-16.

2. 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.

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 Franckowiak, J.D. (Unpublished).

4. Lundqvist, U., and A. Lundqvist. 1988. Induced intermedium mutants in barley: origin, morphology and inheritance. Hereditas 108:13-26.


Lundqvist and J.D. Franckowiak. 1997. Barley Genet. Newsl. 26:472.


U. Lundqvist and J.D. Franckowiak. 2007. Barley Genet. Newsl. 37:279.
J.D. Franckowiak and U. Lundqvist. 2014. Barley Genet. Newsl. 44:180.