杂交粳稻超高产群体干物质生产及养分吸收利用特点

 对超高产与高产杂交粳稻干物质生产及N、P、K养分积累、分配、利用进行了比较研究，结果表明，在干物质生产上，超高产杂交粳稻具有单丛干物重高、群体干物质生产量大，抽穗至成熟期的干物质积累量多、积累比例高，经济系数高的特点。在养分积累、分配与利用上，超高产条件下，稻株对N、P、K三要素的吸收量增加，特别是P、K的吸收量增加明显；成熟期在籽粒与茎中N、P、K的分配比例较高，而在叶片、叶鞘中的分配比例相对较低；同时，养分效率系数、养分收获指数及养分利用效率均高于高产条件下的效率参数，特别是以籽粒产量为计算基础的养分利用效率明显高于高产条件下的养分利用效率。

Characteristics of Dry Matter Production and Nutrient Uptake and Utilization of Super High Yielding Japonica Hybrid Rice

The comparative study on characteristics of dry matter production and nutrient uptake and utilization of japonica hybrid rice was conducted under super high yielding and high yielding conditions. The results showed that the dry matter weight per hill, total yield of dry matter per unit area, the accumulation amount of dry matter from heading to maturity stage and its ratio to total grain yield and the harvest index of super high yielding japonica hybrid rice were higher compared with high yielding rice. The amount of demand for N, P and K, especially the ratios of P and K requirement of super high yielding japonica hybrid rice plant were higher than those of high yielding rice. The allotment ratios of N, P and K in grain at maturity were high and that in leaf and sheath were low in super high yielding japonica hybrid rice compared with high yielding rice. The nutrient efficiency ratio, nutrient harvest index and nutrient use efficiency (NUE) were also higher than those of high yielding rice especially the NUE calculated in terms of grain yield was significant higher than that of high yielding rice.