IV. 6. Coordinator's Report. Chromosome 5.

Jens Jensen, Agricultural Research Department, Risk National Laboratory, DK-4000 Roskilde, Denmark.

An incompletely dominant gene for zoned leaf or zebra striped leaf was associated with chromosome 5 in a trisomic analysis (Furst and Tsuchiya 1983). It has since been confirmed by Shahla and Tsuchiya (1984). This gene occurring in stock Utah T41 was proposed given the gene symbol zb_c2 by Tsuchiya (1983). Later Tsuchiya (1984) proposed the gene symbol should be zb3. At the same time, probably because of a misprint, a different gene has been assigned the same symbol.

A new hordein-coding locus, HrdG has been identified and reported linked with HrdA and HrdB (identical with Hor1 and Hor2, respectively) (Netsvetaev and Sozinov 1984). The recombination percentages from two three-point and one two-point tests are given in Table 1. The recombination percentages were added to previously reported linkage data on chromosome 5 and the linkage map shown in Figure 1 was estimated by the procedure described by Jensen and Jorgensen (1975a, b). Apart from including locus HrdG only minor changes have occurred in relation to the map reported previously. The map positions of M1-at, Pa4, ml-d, and M1-nn are based on less reliable data. Further, I have some unpublished data suggesting that M1-p is not located on chromosome 5.
 

Table 1. Linkage data affecting the 1985 chromosome 5 map. Only recombination percentages underlined are considered. Those marked with an asterisk did not fit and are omitted.
 

Fig. 1. The barley chromosome 5 linkage map with the best fit to all available linkage data. The map positions are given in centimorgans (cM). The order and positions of some M1-loci and of closely linked loci may be indefinite. The position of the centromere is probably slightly above that of locus fs2.
 

References:

Doll, H, and A.H.D. Brown. Hordein variation in wild (Hordeum spontaneum) and cultivated (H. vulgare) barley. Can. J. Genet. Cytol. 21:391-404, 1979.

Furst, E, and T. Tsuchiya. Primary trisomic analysis of three mutant genes in barley. BGN 13:44-46, 1983.

Jensen, J. and J.H. Jorgensen. The barley chromosome 5 linkage map. I. Literature survey and map estimating procedure. Hereditas 80:5-16, 1975x.

Jensen, J, and J.H. Jorgensen. The barley chromosome 5 linkage map. II. Extension of the map with four loci. Hereditas 80: 17-26, 1975b.

Jensen, J., J.H. Jorgensen, H.P. Jensen, H. Giese, and H. Doll. Linkage of the hordein loci Hor1 and Hor2 with the powdery mildew resistance loci M1-k and M1-a on barley chromosome 5. Theor. Appl. Genet. 58:27-31, 1980.

Netsvetaev, V.P. and A.A. Sozinov. Location of a hordein G locus, HrdG, on chromosome 5 of barley. BGN 14:4-6, 1984.

Shahla, A. and T. Tsuchiya. Additional information on the association of zb_c2 for zoned leaf with chromosome 5 in barley. BGN 14:1011, 1984.

Shewry, P.R., A.J. Faulks, P.A. Pickering, I.T. Jones, R.A. Finch and B.J. Miflin. The genetic analysis of barley storage proteins. Heredity 44:383-389, 1980.

Tsuchiya, T. Proposed new gene symbol for two different types for zebra Colorado, or zoned leaf. BGN 13:84, 1983.

Tsuchiya, T. Problems in gene and stock designation and proposed new symbols for zoned or zebra mutants in barley. BGN 14:21-24, 1984.

BGN 15 toc
BGN Main Index