II. 16. Alleles present in loci Horl and Hor2 in a pedigree of European barley.
Ib Linde-Laursen and Hans Doll, Agricultural Research Department, Risø National Laboratory, DK-4000 Roskilde, Denmark.
SDS-polyacrylamide gel electrophoresis separates the barley seed storage protein, hordein, into two groups of polypeptides, hordein-l and hordein-2. The banding patterns of hordein-l and hordein-2 are controlled by codominant alleles at the closely linked loci Horl and Hor2, on chromosome 5. Each separate banding pattern of hordein-l or hordein-2 is controlled by one allele at Horl and Hor2, respectively.
The hordein banding patterns of 50 barley varieties and one population of old Nürnberg barley were determined by SDS-polyacrylamide gel electrophoresis (Doll and Andersen, 1981). The barley varieties were related constituting a pedigree. Details of the pedigree, which represents barley as grown in Northern Europe during the last 100 years, as well as the Giemsa C-banding patterns, the esterase and alpha-amylase isoenzyme types, and the DDT reaction of the varieties will be published elsewhere.
Part of the varieties studied were the same as those tested in the extensive study of Shewry et al. (1979), and our results agree on the whole with theirs. Within hordein-l and hordein-2, respectively, 8 and 13 well-defined polypeptide banding patterns were represented. The patterns differentiated 21 phenotypes. The alleles present in the varieties are given in Table 1. The hordein-l pattern controlled by Hor1Pr was found in two-thirds of the material. In modern varieties (since 1970) it has superceded all other "old" patterns and was dominant together with patterns controlled by the "new" Hor1-alleles, Mo and Ar. Among hordein-2 patterns each of those controlled by Hor2 alleles Rf, Pr, and Ca was found in more than ten varieties; however, 7 were found in one variety only. The larger part of the 21 groups determined by the combined hordein-1/hordein-2 pattern contained only from one up to five varieties. However, two, contained 16 and 13, respectively. Thus, hordein patterns cannot be used as the single criterion for identifying varieties.
The inheritance of the hordein patterns in most cases conformed to expectation, an offspring variety inherited the combined hordein phenotype of one parent. However, 'Carlsberg II' probably has a recombined phenotype although this type was not found in its parent 'Carlsberg'. 'Tyra' has a hordein-l/hordein-2 pattern indicating recombination both between Hor1 and M1-a and between M1-a and Hor2. The earlier reported recombinations (Shewry et al., 1979) between Horl and M1-a in 'Sultan', and between M1-a and Hor2 in 'Sultan', 'Hassan' and in Hor2Pr-plants of 'Ark Royal' were verified.
References:
Doll, H. and B. Andersen. 1981. Preparation of barley storage protein, hordein, for analytical sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Analytical Biochemistry (submitted).
Shewry, P. R., H. M. Pratt, A. J. Faulks, S. Parmar, and B. J. Miflin. 1979. The storage protein (hordein) polypeptide pattern of barley (Hordeum vulgare L.) in relation to varietal identification and disease resistance. J. Natn. Inst. Agric. Bot. 15:34-50.
