II.27 Banding of barley chromosomes.
Ibe Linde-Laursen, Agricultural Research Department. Risø National Laboratory, DK-4000 Roskilde, Denmark. "R".
Additional C-banding patterns of barley chromsomes.
A study of the C-banding patterns of the chromosomes of twenty barley varieties has revealed the existence of more than one banding pattern of each chromosome (Figure 1). Based on this polymorphism, seventeen different banded karyotypes could be made out (Linde-Laursen, 1977). The C-banding patterns of five more varieites and of the mutant 'als', derived from the variety 'Montcalm', have now been established. This has resulted in the finding of two more banding pattern variants of chromosome l, and one more variant of chromsomes 2, 3, and 7, respectively (Figure 2). The Giemsa-banded karyotypes of the six lines (Table 1) show that the karyotypes of the five varieties are different from those of the twenty lines earlier studied, and that the mutant 'als' has the same karyotype as its mother variety. Thus, the use of the C-banding technique has now revealed the existence of a total of twenty-two different C-banded karyotypes among twenty-six barley lines.
Table 1. The C-banded karyotypes of six lines of barley.
Figure 2. Additional banding pattern variants (cf. Fig. 1).
N-banding.
Chromsomes of barley N-banded by the technique of Gerlach (1977) showed the same basic banding pattern as that shown after C-banding with two exceptions; no bands were observed at the secondary constrictions in the short arms of the satellited chromosomes and at the chromosome ends. Owing to rather intense staining of the cytoplasm by the N-banding technique, very small bands, which may be seen by the C-banding technique, could not be observed. The different results of the two banding methods show that at least two kinds of heterochromatin are present in the chromosomes of barley.
References:
Gerlach, W.L. 1977. N-banded karyotypes of wheat species. Chromosoma 62:49-56.
Linde-Laursen, I. 1978. Giemsa C-banding of barley chromosomes. I. Banding pattern polymorphism. Hereditas (in press).
