The Extent and Its Source of Variation for Characteristics Related to Seed Quality of Adzuki Beans : II. Variation of seed coat color among growers lots in Hokkaido area

[摘要] In adzuki beans (Vigna angularis) the degrees of lightness, shade, and uniformity for red color of the seed coat are very important indices on estimation of seed quality in Japan. This study was conducted to evaluate the variation of seed coat color for adzuki beans, which were collected from growers in Hokkaido area in 1987(369 lots) and 1988 (203 lots). Seeds were filled in a cover of petri-dish, adjusted to face without hila, and flattened by pressing with the proper dish. Then, the probe (8 mm in diam.) of a colorimeter was put and moved closely on the surface to measure at different points of visual field. In each seed sample 20 measurements were done and averaged for the values of color indices based on L a b-Color Space. The values of b (degree of yellow), L (lightness), and a (degree of red) varied 34%, 14%, and 8% among seven cultivars, respectively, with higher values of b and L for 0tofuke-shozu, Erimo-shozu, and Takara-shozu. Differences in the seed coat color within cultivars (Erimo-shozu) were detected among locations and years. The values of color indices were associated with the growing period and seed size, being markedly high for b and L at Tokachi District. Seed coat color was widely varied also among growers at the same district, but being much less responsive to post-harvest conditioning (drying period). The values of L, a, and b were closely related to each other within and among cultivars. Obtained data suggest that seed coat color of adzuki beans could be appreciably improved through breeding and management practices.

[学科分类] 农业科学（综合）

[关键词] Adzuki bean;アズキ;Cultivar;種皮色;Producing district;地域間差異;Seed coat color;品質;Seed quality;品種間差異;Vigna angularis