International Database for Barley Genes and Barley Genetic Stocks

BGS 123, Reaction to barley yellow dwarf virus 2 (BYDV), Ryd2

BGN  26:158
Stock number: BGS 123
Locus name: Reaction to barley yellow dwarf virus 2 (BYDV)
Locus symbol: Ryd2

Previous nomenclature and gene symbolization:

Resistance to BYDV 2 = Yd2 (2, 4).
Resistance to BYDV 2 = Ryd2 (3).


Monofactorial incomplete dominant (2, 4).
Located in chromosome 3HL (5); Ryd2.b is about 15.9 cM proximal from the dsp10 (dense spike 10) locus (5).


Plants show an intermediate reaction to BYDV that limits expression of dwarfing and yellow discoloration of leaves (3, 4). Plants with the Ryd2.b gene show less yield and seed size reduction when infected with BYDV and under drought and heat stress.
No images

Origin of mutant:

Natural occurrence in CIho 1227, CIho 1237, CIho 2376, and CIho 14119 (four accessions from Ethiopia) (4, 5).

Mutational events:

Ryd2.b in CIho 1227, CIho 1237, CIho 2376, and CIho 14119 (3, 5); Ryd2.c in Chikurin Ibaraki 1 (CIho 7370, GSHO 783) (susceptible to isolate 2t) (1).

Mutant used for description and seed stocks:

Ryd2.b in Abyssinian (CIho 2376, GSHO 1315); Ryd2.b from CIho 2376 in Bowman (PI 483237)*7 (GSHO 1969); Ryd2.b from CIho 2376 in Glenn (CIho 15769)*8 (GSHO 2370). (Presence of Ryd2 in the Bowman and Glenn lines has not been confirmed).


1. Chalhoub, B.A., A. Sarafi, and H.D. Lapierre. 1995. Partial resistance in the barley (Hordeum vulgare L.) cultivar 'Chikurin Ibaraki 1' to two PAV-like isolates of barley yellow-dwarf virus: allele variability at the Yd2 gene locus. Plant Breed. 114:303-307.
2. Damsteegt, V.D., and G.W. Bruehel. 1964. Inheritance of resistance in barley to barley yellow dwarf. hytopathology 54:219-224.
3. Moseman, J.R. 1972. Report on genes for resistance to pests. Barley Genet. Newsl. 2:145-147.
4. Rasmusson, D.C., and C.W. Schaller. 1959. The inheritance of resistance in barley to the yellow-dwarf virus. Agron. J. 51:661-664.
5. Schaller, C.W., C.O. Qualset, and J.N. Rutger. 1964. Inheritance and linkage of the Yd2 gene conditioning resistance to the barley yellow dwarf virus disease in barley. Crop Sci. 4:544-548.


C.W. Schaller. 1976. Barley Genet. Newsl. 6:123.


J.D. Franckowiak. 1997. Barley Genet. Newsl. 26:158.