International Database for Barley Genes and Barley Genetic Stocks
BGS 604, Proanthocyanidin-free 22, ant22
Stock number: BGS 604
Locus name: Proanthocyanidin-free 22
Locus symbol: ant22
Previous nomenclature and gene symbolization:
Monofactorial recessive (5, 6).
Located in chromosome 2HL (2); ant22.1508 is closely linked to the Zeo2 (Zeocriton 2) locus (2); ant22.1508 is associated with SNP markers 1_1340 to 2_0895 (positions 166.06 to 209.87 cM) in 2H of the Bowman backcross-derived line BW022 (1); likely in 2HL bin 13 based on the lack of recombination with the dense spike trait (Zeo2) (3). Previously located in 7H when the dense spike trait was believed to be controlled by the dsp1 (dense spike 1) gene (1, 3).
No anthocyanin pigmentation is observed in the vegetative parts of the mutant plants. The testa layers of the grains of the ant22 mutants lack proanthocyanidins and catechins but accumulate homoeriodictyol and chrysoeriol (7, 8). It is likely that the ant22 gene codes for one subunit and the ant17 gene for the other subunit of the dimeric flavanone 3-hydroxylase enzyme, which catalyzes the conversion of flavanones into dihydroflavonols (7, 9). Plants of the Bowman backcross-derived line BW022 were slightly shorter than Bowman and shorter rachis internodes, 3.4 vs. 4.6 mm. The kernels of BW022 plants were 5 to 10% lighter and slightly shorter and thinner. The reduced in grain size appear to be an effect of the ant 22.1508 allele in BW022 while reductions in culm length and rachis internode length appeared associated with the Zeo2 allele (3). A close linkage of the ant22.1508 allele to the short rachis internode trait was observed in BW022 (3), But instead of dsp1 (dense spike 1) in 7H, the critical dense spike trait was shown to be in 2HL where the Zeo2 gene is located (2).
Origin of mutant:
A sodium azide induced mutant in Hege 802 (4).
ant22.212 in Hege 802 (4); ant22.603 (CN 37389) in Harrington (6); ant22.1500, 22.1501, 22.1504 in Amagi-Nijo (4); ant22.1508 (NGB 13705, GSHO 1635) in Haruna-Nijo (5).
Mutant used for description and seed stocks:
ant22.1508 (NGB 13705, GSHO 1635) in Haruna-Nijo; ant22.1508 in Bowman (PI 483237)*3 (GSHO 1841); ant22.1508 in Bowman*6 (BW022, NGB 20430).
1. Boyd, P.W., and D. E. Falk. 1990. (Personal communications).
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. Jende-Strid, B. 1978. Mutation frequencies obtained after sodium azide treatments in different barley varieties. Barley Genet. Newsl. 8:55-57.
5. Jende-Strid, B. 1984. Coordinator's report: Anthocyanin genes. Barley Genet. Newsl. 14:76-79.
6. Jende-Strid, B. 1991. Coordinator's report: Anthocyanin genes. Barley Genet. Newsl. 20:87-88.
7. Jende-Strid, B. 1993. Genetic control of flavonoid biosynthesis in barley. Hereditas 119:187-204.
8. Jende-Strid, B., and K. N. Kristiansen. 1987. Genetics of flavonoid biosynthesis in barley. p. 445-453. In: S. Yasuda and T. Konishi (eds.) Barley Genetics V. Proc. Fifth Int. Barley Genet. Symp., Okayama 1986. Sanyo Press Co., Okayama.
9. Meldgaard, M. 1992. Expression of chalcone synthase, dihydroflavonol reductase, and flavanone 3-hydroxylase in mutants in barley deficient in anthocyanin and proanthocyanidin biosynthesis. Theor. Appl. Genet. 83:695-706.
B. Jende-Strid. 1999. Barley Genet. Newsl. 29:95.
J.D. Franckowiak 2011. Barley Genet. Newsl. 41:191-192.