新株型水稻与杂交稻结实期的光合特性与产量

以穗型较大的3个不同类型水稻品种(组合)新株型稻IR65600-85、二系杂交稻培矮64S/E32和三系杂交稻 优86为材料,研究其结实期干物质生产与分配的比较特性及与产量的关系.结果表明:培矮64S/E32和 优86产量差异不显著,但它们极显著地高于IR65600-85.就单茎物质生产力而言,IR65600-85具有较高的生物产量,归因于其株型紧凑、少蘖大穗、分蘖成穗率高、单茎茎鞘重、光合速率高,但由于抽穗后叶、茎、鞘物质输出受阻,导致功能叶碳氮代谢紊乱,比例失调,使籽粒结实率低、充实差,产量潜力无法发挥.

Photosynthetic characteristics and yields of new plant type rice and hybrid rice at grain-filling stage

Three different rice cultivars, characterized by a larger panicle type, such as new plant type rice IR65600 85, two line cross Peiai64S/E32 and three line cross Eryou86 were used for the experiment to investigate the comparative properties of the production and the partitioning of the dry matter and its relationship with the grain yield during the grain filling stage. The results indicated that: there was no significant difference in the yields between Peiai64S/E32 and Ⅱ you86, but the yield of the two cultivars was significantly higher than that of IR65600 85 respectively. As far as the production capability of single stem was concerned, the new plant type had a well organized plant appearance, showing its less tillers, larger panicles,higher rate of available panicles,heavier weight of single stem sheath and higher rate of photosyntheses, which were attributed to its high biologic yield, but the transportation of carbon reserves in the leaf stem sheath of IR65600 85 was inhibited in late stage of the grain filling, resulting in metabolic disorder and imbalance of carbon nitrogen in the functional leaves,in turn led to decreased nitrate reductase activity in the leaves, consequently reduced percentage of filled grains and yield and hindered the realization of the yield potential of the rice cultivar.