BGS 580, Praematurum-d, mat-d

Early 14 = ea-d14 (5).
Early maturity-d = ea-d (10).

Monofactorial incomplete dominant (5).
Located in chromosome 4HL or 6HL (2); the narrow leaf blade trait from mat-d.14 is associated with SNP markers 2_1130 to 1_1019 (positions 175.48 to 183.54 cM) in 4H bins 12 to 13 and with SNP markers 1_0734 to 2_0379 (positions 159.32 to 163.56 cM) in 6H bins 12 to 13 of the Bowman backcrossed-derived line BW509 (2).

Early heading mutants at the mat-d locus (6) have a moderate increase in earliness (heading 3 days earlier than the parents) under field cultivation in Sweden (7, 8). When grown under controlled environmental conditions, mutants are photo- and thermoperiod sensitive and are classified as a pronounced long-day type (4). Early heading is also associated with increased culm length and grain yield. The length of the peduncle is increased and mutants have longer spikes. Compared with the drastic maturity mutants at eam8 (mat-a), mat-b, and mat-c loci, mutants at the mat-d locus have a normal number of the culm internodes (1, 5). Retention of the mat-d.14 mutant in the Bowman backcross-derived line, BW509, needs to be confirmed because only plants with narrower leaf blades were recovered in progenies from crosses to Bowman. An error could have been made during backcrossing because BW509 retained SNP molecular markers in chromosome 4HL that are identical to those retain in BW513, the Bowman backcross-derived line for mat-h.36 (see BGS 584) (2). Phenotypically BW509 and BW513 were very similar (3). BW509 and Bowman plants were phenotypically similar except for reduce leaf blade width and slightly lower grain yield (3).

An X-ray induced mutant in Bonus (NGB 14657, PI 189763) (5).

mat-d.14 (NGB 110014, GSHO 1790) in Bonus (NGB 14657, PI 189763) (3); mat-d.124 (NGB 110124) in Foma (NGB 14659, CIho 11333) (7, 8, 9).

mat-d.14 (NGB 110024, GSHO 1790) in Bonus; mat-d.14 in Bowman (PI 483237)*6 (BW509, NGB 20737).

1. Dormling, I., and Å. Gustafsson. 1969. Phytotron cultivation of early barley mutants. Theor. Appl. Genet. 39:51-61.

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 Franckowiak, J.D. (Unpublished).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. Gustafsson, Å., I. Dormling, and U. Lundqvist. 1982. Gene, genotype and barley climatology. Biol. Zent. Bl. 101:763-782.

5. Gustafsson, Å., A. Hagberg, and U. Lundqvist. 1960. The induction of early mutants in Bonus barley. Hereditas 46:675-699.

6. Gustafsson, Å., A. Hagberg, U. Lundqvist, and G. Persson. 1969. A proposed system of symbols for the collection of barley mutants at Svalöv. Hereditas 62:409-414.

7. Lundqvist, U. 1991. Swedish mutation research in barley with plant breeding aspects. A historical review. p. 135-148. In Plant Mutation Breeding for Crop Improvement. Proc. Int. Symp. Vienna, 1990. Int. Atomic Energy Agency, Vienna.

8. Lundqvist, U. 1992. Coordinator's report: Earliness genes. Barley Genet. Newsl. 21:127-129.

9. Lundqvist, U. (Unpublished).

10. Søgaard, B., and P. von Wettstein-Knowles. 1987. Barley: genes and chromosomes. Carlsberg Res. Commun. 52:123-196.

U. Lundqvist and J.D. Franckowiak. 1997. Barley Genet. Newsl. 26:507.

U. Lundqvist and J.D. Franckowiak. 2015. Barley Genet. Newsl. 45:208-209.