Deep-seeding tolerance is required in the semi-arid regions where the soil surface is very dry during the early growing season. Diallel analysis of the deepseeding tolerance which was evaluated by the percent of seedling emergence from 12 and 15cm seeding depth was performed using 10×10 reciprocal crosses of various types of barley varieties (Exp. 1) and from 9 and 12cm seeding depth using 9×9 two-rowed varieties (Exp. 2). The deep-seeding tolerance was controlled by over-dominant genes. The positive direction was dominant, and the reciprocal effect was statistically significant. The heritability in the broad sense was 0.88 for 12 and 15cm seeding depths, and that in the narrow sense was 0.14 for 12cm and 0.19 for 15cm depths. Deepseeding tolerance showed a positive correlation with the coleoptile length and the first internode length. The inheritance of the latter two traits was very similar to that of the deep-seeding tolerance. The correlation coefficient between deep-seeding tolerance and 1, 000 kernel weight was as low as 0.3 and the inheritance mode of these traits was different. In another experiment, in the Exp. 2, the dominance effect was not significant and the heritability in the narrow sense was high (0.65 for 9cm and 0.77 for 12cm depths). The correlation of deepseeding tolerance with coleoptile length, and that with 1, 000 grain weight were high. The practical importance of the deep-seeding tolerance in the semi-arid regions, and the breeding strategy were discussed.

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From 1993 to 1996, thirty-one accessions of sweet potato wre analyzed for their insoluble and soluble dietary fiber (IDF and SDF) content in the storage roots to determin their varietal differences. Mean values of the IDF content and SDF content for four years in each stain ranged from 4.2 to 9.9% and 2.0 to 5.7%, respectively. Mean values of the IDF content and SDF content in each year ranged form 4.9 to 6.2% and 3.1 to 3.5%, respectively. The analysis of variance showed that the differences among strains and years were significant at the 1% level for the IDF, SDF and TDF contents. The estimated heritability values of the IDF, SDF and TDF content were 0.55, 0.75 and 0.68, respectively, indicating that the selection of the dietary fiber content was effective. Each dietary fiber content was negatively correlated with the dry matter content at the 1% level, and the IDF content was negatively correlated with the yield at the 5% level. These finding indicate that the dietary fiber content is low in the strains with a high dry matter and high storage root yield. However, there was no significant correlation between the SDF content and the storage root yield, indicating that the selection of strains with a high SDF content and a high storage root yield is possible.

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We examined a method for evaluating flour color by determining the color of the cross-section of wheat endosperm unaffected by mixed bran. Samples were prepared as follows. The grains were cut crosswise into 2mm-thick slices, the seed coat was removed and the grains were soaked in distilled water. The color value, lightness (L), redness or greenness (a) and yellowness or blueness (b) of the cross-section of the samples were determined using a microspectrocolorimeter. The L value was stabilized after 4hours from soaking in distilled water. The three color values for the crosssection were highly correlated with those of the pure endosperm powder devoid of mixed bran. Furthermore, the flour color estimated from the color of the crosssection was consistent with the flour color determined by the standard method (color of flour paste determined with a spectrophotometer) for yellowness, but not for L value, because the estimation by the standard method was affected by mixed bran. There was a high correlation with a and b in the color of the cross-section of the endosperm from 24 Japanese and foreign varieties. The hue of the endosperm color of these varieties was similar (slightly greenish yellow), and the degree of yellowness of the endosperm increased in proportion to the chromaticity. Furthermore, the highly positive correlation between the chromaticity suggested that b, suggesting that b is useful for selecting for endosperm yellowness. We compared the color of the pure endosperm powder and the color of the flour obtained by milling using a Brabender test mill. Mixed bran lowered the L value of flour and the degree of decrease was different with the variety. Some varieties and strains had a high L value in the cross-section, irrespective of the hardness and protein content. Strains with a bright endosperm color could be selected in both soft and hard wheat, irrespective of protein content.

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