A Database for Triticeae and Avena
II. 33. Linkage and effect of the earliness gene ea,,c, involved
in Chinese cultivars on yield and yield components in barley.
S. Yasuda and J. Hayashi, The Ohara Institute for Agricultural Biology,
Okayama University, Kurashiki, Japan.
An earliness gene, ea,,c, involved in Chinese native cultivars
reported previously (BGN Vol. 8:127) was further analyzed to establish
the location on chromosome and to know the effects of the gene on yield
and its components.
Linkage study was carried out in F2 and their F3 progenies of a cross
between Chinese early cultivar, Tayeh 8, and a late strain, K-gl3, with
hooded lemma and glossy leaf characters. Linkage data and a map of three
genes on chromosome 4 are given in Table 1 and Fig. 1. It was confirmed
that ea,,c was located in almost mid-point between K and
Table 1. F2 and F3 data for linkages of three
genes, ea,,c, K and gl3, obtained in a cross of Chinese
early cultivar Tayeh 8 with late one, K-gl3.
Figure 1. A map of three genes on chromosome 4.
Fifty-five F3 lines derived from non-glossy plants among F2 population
were grown in a field in fall with two replications, and investigated yield
and its components on a single plant basis. Among them, 19 and 20 F3 lines
homozygous for early and late heading, respectively, were compared for
yielding characters, though glossy leaf segregants, when appeared, were
excluded for the measurements. As to hooded and awned type plants, measurements
of these two types were calculated together, because of no differences
in yielding characters between them.
The results indicated that the early lines about 13 days earlier in
heading time, shorter in stem and ear length, lower in straw weight and
less in number of grains per ear than those of the late ones, respectively.
On the other hand, there were no differences in number of ears between
the early and late lines, and higher values of 1000 kernel weight and harvest
index were found in early lines as compared with late ones. As a consequence,
the early lines were found to be about 5g lower in grain weight in an average
than the late ones (Table 2). It was also found that the most important
component for high yield was number of grains per ear for the early lines
and number of ears per plant for the late lines (Table 3). It may be noted
that the effects of ea,,c on yield components, obtained here, are
quite similar to those of the very early gene, eak, involved
in Kinai 5 and Mari (see BGN 8:125).
Table 2. Comparison of mean values between early
and late line groups.
Table 3. Correlation coefficients between grain
weight per plant (Y) and seven characters (x's), and partial standard regression
coefficients (b') of Y on x's
BGN 10 toc
BGN Main Index