GENES FOR POWDERY MILDEW REACTION

During the years 1982-1987 an annually updated list of genes (alleles) for powdery mildew reaction in barley has been published. A few changes and additions were made in BGN 18: 120-134, 1988 and BGN 19: 27-32, 1989. Since then detailed data are published on gene Ml(Ga) by Hossain and Sparrow (199la, b). Jørgensen (1991) showed that genes Mlc and Ml(1402) are near or at locus Mla and designated them Mla22 and Mla23, respectively. Jahoor et al. (1989) presented data on the genetics of resistance in two barley lines derived from H. spontaneum, and concluded that they each possessed one gene that were alleles in locus Mlp. These genes were proposed designated Mlp2 and Mlp3, respectively. These designations should, however, not be accepted because the data are ambiguous.

The following list of gene loci affecting disease and pest reaction in barley is compiled based on the comprehensive list of gene loci in barley published by Sogaard and Wettstein-Knowles (1987). The list is updated to ultimo 1990.

REFERENCES

Hossain, M.A. and D.H.B. Sparrow. 1991a. Resistance to powdery mildew (Erysiphe graminis f.sp. hordei) in the cultivar Galleon. I. Relationships with known genes for resistance. Euphytica 52: 1-9.

Hossain, M.A. and D.H.B. Sparrow. 1991b. Resistance to powdery mildew (Erysiphe graminis f.sp. hordei) in the cultivar Galleon. II. Chromosomal location and linkage with hordein protein genes. Euphytica 52:11-17.

Jahoor, A., A. Ludwig and G. Fischbeck. 1989. New genes for powdery mildew resistance in Hordeum spontaneum derived lines alleles or closely linked to the Mlp locus. Barley Genetics Newl. 19: 23-26.

Jørgensen, J.H. 1991. Powdery mildew resistance genes Mla22 and Mlo23 in barley. In: (L. Munck, ed.) Barley Genetics VI Vol. 1. Munksgård Intern. Publ. Copenhagen pp. 596-598.

Søgaard, B. and P. von Wettstein-Knowles. 1987. Barley: Genes and chromosomes. Carlsberg Res. Comm. 52: 123-196.