A Database for Triticeae and Avena
Three loci for esterase isozymes (Est1, Est2, and Est4) are tightly
linked as a complex locus (Kahler and Allard, 1970; Nielsen and
Frydenberg, 1971a), and located on chromosome 3 (Nieslen and Frydenberg,
1971b). Recently, Konishi and Matsuura (1987) found that Est4 locus is
linked with the cu2 locus with a recombination value of 23.8 ± 1.79% and
localized at the terminal of the long arm of chromosome 3. The
recombination value was estimated to be 25.2 ± 4.08% after recalculation,
using F2 and F3 data in the same combination (Konishi and Matsuura, 1990).
Furthermore, a new isozyme locus, Aat3 for aspartate
aminotransferase-3, was found to be linked with uz locus with a
recombination value of 3.2 ± 0.78%, suggesting that Aat3 locus is located
near the centromere of chromosome 3 (Konishi and Matsuura, 1990).
The orientation of 18 loci on chromosome 3 was estimated by a
computer program for the maximum likelihood method developed by Jensen and
Jørgensen (1975), using data obtained in our institute (see the references
in BGN 17:110). The result is indicated in Fig. 1.
Kahler, A.L., and R. W. Allard. 1970. Genetics of isozyme variants in
barley. I. Esterase. Crop Sci. 10:444-448.
Konishi, T., and S. Matsuura. 1987. Linkage analysis of Est-4 locus for
esterase isozyme-4 in barley. BGN 17:68-70.
Konishi, T., and S. Matsuura. 1990. Chromosomal localization of two
isozyme loci on chromosome 3 in barley. BGN 19:46-48.
Jensen, J., and J. Helms Jørgensen. 1975. The barley chromosome 5
linkage map. I. Literature survey and map estimation procedure.
Nielsen, G., and 0. Frydenberg. 1971a. The inheritance and distribution
of esterase isozymes in barley. In Barley Genetics 11:14-22.
Nielsen, G., and 0. Frydenberg. 1971b. Chromosome localization of the
esterase loci Est-1 and Est-2 in barley by means of trisomics.