两个高产两系杂交稻组合形态与产量形成特征的研究

对两个高产两系组合与两个三系对照组合的比较研究表明，该两个两系杂交稻组合具有以下形态及产量形成特征；剑叶较长，穗下节间长，基部节间短且茎壁较厚，叶片直立性好，叶披垂度小；群体中、下部透光性能好；干物质总积累量大，但茎鞘物质转运率小，总库容大，源库比较小；群体穗数少，穗粒数多，粒重小，结实率稍低。

Morphological Characteristics and Formation of Yield in Two High-yielding Two-line Hybrid Rice Combinations

The morphological characteristics and the formation of yield in two two line and two three line hybrid rice combinations were studied and compared. The results showed that two line hybrid rice combinations had a longer flag leaf, a longer first internode from top, shorter basal internodes with thicker stem walls, a smaller leafing angle with less leaf drooping, a better light penetration through the mid to lower levels of the population, a much greater dry matter production and bigger grain sink and much more spikelets per panicle. However, two line hybrid rice combinations had also a lower rate of translocated dry matter from stem and sheath, a smaller ratio of source to sink, a smaller population with fewer panicles, lighter grains and a little lower seed setting rate.