BGS 96, Reaction to Puccinia hordei 15 (barley leaf rust), Rph15

Rph16 = Reaction to Puccinia hordei 16 (6, 9).

Monofactorial dominant (1, 2).
Located in chromosome 2HS (1, 6); Rph15.ad is over 32.3 cM proximal from the vrs1 (six-rowed spike 1) locus (1); in bin 2H-6 near molecular markers MWG874 (6) and MWG2133 (9); cosegregation with AFLP marker P13M40 (9); about 25.2cM distal from the centromere (9); about 14 cM proximal from the Eam1 (Early maturity 1) locus (3).

The seedling reaction to most isolates of Puccinia hordei is a relatively large necrotic fleck, hypersensitive reaction (1). The seedling infection type of heterozygotes is indistinguishable from that of homozygous resistant seedlings. Alleles at this locus were found in six of the first seven Rph genes from Hordeum vulgare subsp. spontaneum evaluated in Bowman backcross-derived lines (1, 2). The Rph15 locus is likely allelic to Rph16 based on the failure to recover susceptible recombinants (9). Only one of the 350 leaf rust isolates (90-3 from Israel) was found to be virulent on Rph15 lines (4, 9). Resistance to isolate 90-3 was observed in progeny from a cross between a line with Rph15 to another source of leaf rust resistance (8). Rph15 represents one of the most effective leaf rust resistance genes reported in Hordeum vulgare (9).

Natural occurrence in accession PI 355447 of Hordeum vulgare subsp. spontaneum, but isolated in a selection that contained one Rph gene from the original accession crossed to Bowman (PI 483237) (1, 7).

Rph15.ad in PI 355447 (GSHO 1586) (1, 2, 5), PI 354937, PI 391024, PI 391069, PI 391089, and PI 466245 (1, 2); Rph15.ae from HS084 (6, 9); PI 466245 has at least two genes for leaf rust resistance (7).

Rph15.ad PI 355447 (GSHO 1586); Rph15.ad from PI 355447 in Bowman*8 (GSHO 2330, PI 643164, BW719, NGB 33425). (The Rph15.ad gene from other Hordeum vulgare subsp. Spontaneum accessions may be present in about 40 other BW lines).

1. Chicaiza, O. 1996. Genetic control of leaf rust in barley. Ph.D. dissertation, North Dakota State Univ., Fargo.
2. Chicaiza, O., J.D. Franckowiak, and B.J. Steffenson. 1996. New sources of resistance to leaf rust in barley. pp. 706-708. In A.E. Slinkard, G.J. Scoles, and B.G. Rossnagel (eds.). Proc. Fifth Int. Oat Conf. & Seventh Int. Barley Genet. Symp., Saskatoon. Univ. of Saskatchewan, Saskatoon.
3. Falk, A.B. (Personal communications).
4. Fetch, T.G. Jr., B.J. Steffenson, and Y. Jin. 1998. Worldwide virulence of Puccinia hordei on barley. Phytopathology 88:S28.
5. Franckowiak, J.D., Y. Jin, and B.J. Steffenson. 1997. Recommended allele symbols for leaf rust resistance genes in barley. Barley Genet. Newsl. 27:36-44.
6. Ivandic, V., U. Walther, and A. Graner. 1998. Molecular mapping of a new gene in wild barley conferring complete resistance to leaf rust (Puccinia hordei Otth). Theor. Appl. Genet. 97:1235-1239.
7. Jin, Y., and B.J. Steffenson. 1994. Inheritance of resistance to Puccinia hordei in cultivated and wild barley. J. Hered. 85:451-454.
8. Sun, Y., J.D. Franckowiak, and S.M. Neate. 2005. Reactions of barley lines to leaf rust, caused by Puccinia hordei. Proceedings of the 18th North American Barley Researchers Workshop (​http:​/​​/​www1.agric.gov.ab.ca​/​$department​/​deptdocs.nsf​/​all​/​fcd8068​), July 17-20, 2005, Red Deer, Alberta, Canada http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/fcd10135#Reactions
9. Weerasena, J.S., B.J. Steffenson, and A.B. Falk. 2004. Conversion of an amplified fragment length polymorphism marker into a co-dominant marker in the mapping of the Rph15 gene conferring resistance to barley leaf rust, Puccinia hordei Otth. Theor. Appl. Genet. 108:712-719.

J.D. Franckowiak and O. Chicaiza. 1998. Barley Genet. Newsl. 28:29.

J.D. Franckowiak. 2005. Barley Genet. Newsl. 35:186.
J.D. Franckowiak. 2007. Barley Genet. Newsl. 37:214-215.