Consideration on the Mechanism of Expression of Dwarf Genes in Rice Plants. II. The Actions of Dwarf Genes on Cell Division and Cell Elongation in Parenchyma of Internode.

The present stucly was attempted to investigate how some dwarf genes act on cell division and cell elongation in internodes of rice plants. Materials used were five dwarf rice varieties differing one another in internode distribution patterns in culm, namely, M342, Tanginbozu, Sankei 10, Kotake-tamanishiki and Shoryu-shinriki, and four normal rice varieties having close genetic relations to each of the dwarf rice varieties mentioned above, namely, Norin 8, Ayanishiki, Tamanishiki and Shinriki 11. Two parenchyma cell files, file A, being in a row just inside the vascular bundle, and file B, the third cell file counted from the file A to the central lacuna of internode, were observed for measurement of cell numbers per file and cell length in each of upper five internodes.