Gene for Resistance to Barley Mild Mosaic Virus in German Winter Barley Located on Chromosome 3L

Abstract

In order to identify the chromosome arm carrying a gene for resistance to barley mild mosaic virus (BaMMV) in German winter barley cultivars, a line trisomic for the long arm of chromosome 3 (telotrisomic 3L) was crossed to the resistant cvs. 'Sonate' and 'Ogra'. Results of tests for BaMMV reaction in the F2 indicate that the gene for resistance in German cultivars is located on the long arm of chromosome 3.

Localisation and combination of resistance genes against soil-borne viruses of barley (BaMMV, BaYMV) using doubled haploids and molecular markers

“…Resistance to BaMMV and BaYMV-1 was detected in Germany soon after the first discovery of the disease and it turned out by segregation analyses, trisomic and telotrisomic analyses, that resistance is caused by a single recessive gene located on chromosome 3HL (Kaiser and Friedt 1992;Graner and Bauer 1993), which was later named rym4. In successive years it was shown, in extensive screening programmes, that resistance to the barley yellow mosaic virus complex is quite common in the primary barley gene pool and is conferred by different recessive resistance genes located in different regions of the barley genome and being effective against all or single members of the barley yellow mosaic virus complex (for review cf.…”

Potential and limitations of isozymes for chromosomal localization of resistance genes against barley mild mosaic virus (BaMMV)

“…Using mechanical inoculation of BaYMV, Friedt et al (1983) have identified a resistance gene, later named ym4 (Friedt et al ., 1990), which is believed to be present in all modern resistant German cultivars . This gene was assigned to the long arm of chromosome 3 (3H) with the aid of a set of trisomic (Kaiser & Friedt, 1989) and telotrisomic (Kaiser & Friedt, 1992) lines . As no susceptible plants appeared in F2 progenies derived from crosses between 'Mokusekko 3' and the resistant German varieties, it was assumed that this cultivar carried a gene allelic or tightly linked to ym4 (Friedt & Foroughi-Wehr, 1986) .…”

Basic and applied aspects of the genetic analysis of the ym4 virus resistance locus in barley

“…Although there are several classes of resistance against one or more virus strains , the resistance of almost all cultivars rests on a single recessive gene, which confers complete immunity against BaMMV and BaYMV-1. This ym4 gene has been located on the long arm of barley chromosome 3 by means of telotrisomic analysis (Kaiser and Friedt, 1992) and, later, by the aid of RFLP markers (Graner and Bauer, 1993) to the distal portion of this chromosome arm. Two tightly linked RFLP markers (MWG010 and MWG838) have been identified, providing the basis (1) for marker-assisted selection in resistance breeding programmes and (2) for a high resolution mapping strategy around the ym4 locus, which, in turn, is a prerequisite for a mapbased cloning approach.…”