GrainGenes
A Database for Triticeae and Avena
Yasuda and Hayashi, pp. 74-76
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 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
