International Database for Barley Genes and Barley Genetic Stocks

BGS 675, Mottled leaf 9, mtt9

BGN  44:207
Stock number: BGS 675
Locus name: Mottled leaf 9
Locus symbol: mtt9

Previous nomenclature and gene symbolization:

Mutant 2721 (2).


Monofactorial recessive (2, 3).
Location is unknown (3). The Bowman line for mtt9.2721 (BW598) differs from Bowman only for SNP markers near the Rph3 (reaction to Puccinia hordei 3) locus (1).


Leaf blades of the mtt9.2721 plants are characterized by chlorotic leaf spots and bands that coalesce and eventually form large white patches. The phenotype is displayed on all leaves. As the leaves mature, the white regions gradually become darker, seeming to undergo necrosis and death. Often the necrosis affects the leaf edges, resulting in wrinkled leaf edges. Under short day conditions, expression of the mutant phenotype is delayed by several days and is reduced in severity (2, 3). Initially the chlorosis of mtt9.2721 plants appears similar to that produced by the mtt2 (mottled leaf 2) and mtt6 (mottled leaf 6) mutants (2, 3). Autofluorescence is clearly noticeable in the cell walls or apoplastic compartments of the bleached leaf tissues, and is more pronounced in the vascular tissues. The green tissues display little or no autofluorescence. The cell walls of leaf blade lesions are clearly thickened (3). The mtt9.2721 plants were more susceptible to Pyrenophora teres f. teres than Bowman-Rph3.c based on counting the number of spores produced on leaf surfaces (3).

Origin of mutant:

A fast neutron induced mutant in Bowman-Rph3.c (Bowman*11//Estate/3.2 uz als MM) (BW746, PI 643152, NGB 22452) (2, 3).

Mutational events:

mtt9.2721 (NGB 23524, GSHO 3598) in Bowman-Rph3.c (Bowman*11//Estate/3.2 uz als MM) (PI 643152, NGB 22452) (2, 3).

Mutant used for description and seed stocks:

mtt9.2721 (NGB 23524, GSHO 3598) in Bowman Rph3.c (BW746, PI 643152, NGB 22452); mtt9.2721 from Bowman Rph3.c in Bowman (PI 483237) (BW597, NGB 22163).


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. 2010. Genetic dissection of barley morphology and development. Plant Physiol. 155:617-627.

2. Wright, S.A.I., M. Azarang, and A.B. Falk. 2007. Four new barley mutants. Barley Genet. Newsl. 37:34-36.

3. Wright, S.A.I., M. Azarang, and A.B. Falk. 2013. Barley lesion mimics, supersusceptible or highly resistant to leaf rust and net blotch. Plant Path. 62:982-992.


S.A.I. Wright, A.B. Falk, J.D. Franckowiak, and U. Lundqvist. 2013. Barley Genet. Newsl. 43:183.


S.A.I. Wright, A.B. Falk, J.D. Franckowiak, and U. Lundqvist. 2014. Barley Genet. Newsl. 44:207.