@article{oai:niigata-u.repo.nii.ac.jp:00002755,
 author = {笹原, 英樹 and 福山, 利範},
 issue = {2},
 journal = {育種学研究, 育種学研究},
 month = {Jun},
 note = {穂首維管束系と収量構成要素との関係を調査するため, 1998年に温帯日本型に属するイネ29品種(日本産22品種および中国産7品種の在来, 改良品種)を1区9個体, 2反復で栽培した.穂首節間大維管束数(以下, 大維管束数)は9.6から18.9の変異を示し, 品種間で有意に異なっていた.次に, 一次枝梗あたりの大維管束数(維管束比)を求めたところ, これらの品種は1.2を境に低維管束比群(低比群)と高維管束比群(高比群)の2つに判別できた.これら2群の間では出穂日に差異はみられなかったが, 桿長は高比群が, 穂数は低比群が有意に大きかった.また, 高比群は種子稔性が若干低かったものの, 二次枝梗上粒数が低比群よりも有意に多く, 粒重は両群で大きな違いはみられなかった.したがって, 高比群では過剰の大維管束が二次枝梗上頴花の増加を促すだけでなく, 増加した頴花への光合成産物の転流にも関わっていると考えられた.しかし, 高比群の品種は二次枝梗上頴花数が多く穂重が重い反面, 穂数が少ないために一株籾重は低比群よりも低くなっていた.以上のことから, 維管束比の高い品種を育成することで日本型品種, 特に穂重型品種では, 収量性をさらに改善できるものと思われた., The relationship between the vascular bundle system in a peduncle and the yield components was investigated using 29 temperate-japonica rice varieties, Oryza sativa L., which consisted of 22 Japanese and 7 Chinese improved and native varieties. Nine plants of each variety were cultivated in the field in 1998 with two replications. The number of large vascular bundles(Vb)in a peduncle differed significantly between the varieties ranging from 9.6 to 18.9. According to the ratio of the number of Vb to the number of primary rachis branches, V/R ratio, the 29 varieties were divided into 2 groups ; those with high(>1.2)and low(≤1.2)V/R ratio. No difference was found in heading date between the varieties with high and low V/R ratio, but the culm length and panicle number were respectively, higher and lower in the varieties with a high V/R ratio than in those with a low V/R ratio. The varieties with a high V/R ratio showed a larger number of spikelets and grains on the secondary rachis branches, but no difference was observed in the grain weight between the 2 groups. It was assumed that the excess of vascular bundles in the varieties with a high V/R ratio indicated that the secondary-branch spikelets had developed and well filled with photosynthetic products. The varieties with a high V/R ratio showed a heavier panicle weight, but lower grain weight per plant because of the lower number of panicles as compared with the varieties with a low V/R ratio. The significance of the vascular bundle system in breeding for a high yielding ability was discussed.},
 pages = {77--81},
 title = {日本型イネ品種における穂首維管束系と収量構成要素との関係},
 volume = {1},
 year = {1999}
}