Studies on the yield stability viewed from the point of character manifestation variability of crops IV : On the intra-plant variations of culm length and internode length in rice (Agriculture)

稈長の1個体内における変異を各節間長の個体内変異に分解して検討するために, 水稲11品種を供試し, 各品種20個体について全分けつの上位4節間長と第5節間以下の総節間長を調査し, 各節間長の個体内変異が稈長のそれに及ぼす効果を分析した。稈長の個体内変異はいずれの節間長におけるよりも大きく, また各節間の間では第1節間長の変異が最大となり, 第2,第3節間長の変異は概して小さかった。一方, この個体内変異を各々の長さとの割合でみた場合には, 下位節間長の変異がかなり大きい値を示した。稈長と各節間長との個体内相関はいずれの場合にも正の値を示し, 各節間が長くなる程長稈になる傾向を示したが, この関連性は第2節間において最小であった。稈長の個体内変異に対する各節間長の個体内変異の寄与率は, 品種によってかなり異なるパターンを示したが, 一般に第1節間における寄与が最大で, 第2節間の寄与はきわめて小さかった。
The relationship between the intra-plant variation of culm lengths, and the intra-plant variations of the five internodes lengths in 11 paddy rice varieties was investigated. Twenty mature plants in each variety were sampled, and the upper four internodes lengths and the total length of remainig internodes of all the culms contained within a plant were examined. The intra-plant variation of the first internode lengths was largest of the five internodes lengths variations, whereas the variations of the second and the third internodes lengths were small. All the intra-plant correlation coefficients between culm length and the internodes lengths were positive. The relationship was smallest in the second internode length. The patterns of contribution rates due to the intra-plant variations of the five internodes lengths, to that of culm lengths varied with different varieties. In general, the contribution rate due to the first internode length was largest, whereas that due to the second internode length was very small.