Basic Studies on the Cultivation and Breeding of Brewers' Rice in Kagawa Prefecture : Effect of the selection for leaf color on the protein content and some other brewing characteristics in late generation(Genetic Resources cnd Evluation)

Abstract

The effect of the selection for leaf color in early generations on the grain-protein content and some other brewing characteristics in late generation was investigated in the crosses of Ooseto with Yamadanishiki and Ooseto with Matuyamamii. The leaf color (SPAD) values at heading time in the F₂ population showed a normal distribution. The broad-sense heritabilities of leaf color estimated from F₂ variance were 0.517 in the cross of Ooseto with Yamadanishiki and 0.397 in the cross of Ooseto with Matuyamamii. The selection for leaf color at heading time toward dark color (H group) and light color (L group) was continued from the F₂ generation to F₅ generation. In F₆ lines, the mean value of the protein content of the H group was significantly higher than that of the L group. Plant length was longer and 1000 grain weight was lighter in the H group than in the L group. Days from transplanting to heading was shorter and the percentage of white core rice was higher in the H group. There was a significant correlation between the leaf color and the protein content. However, some lines in the H group had a higher protein content than the others at the same level of leaf color. The F₅-F₆ parent-offspring correlation of the leaf color was significant. From those results, it is considered that the leaf color at heading time in early generation can be used as a criterion for the selection for protein content.