品种更替对中熟粳稻氮素吸收的影响

以江苏省各时期代表性中熟粳稻品种为材料,研究了在品种更替过程中氮素吸收的变化规律。结果表明,各主要生育期植株氮素积累量均表现为现代品种显著或极显著高于早期品种;各类型品种氮素积累均主要集中在拔节期-抽穗期,且此阶段营养元素吸收占整个生育期养分吸收的比例随品种更替呈不断上升的趋势;早期品种在成熟期仍有大量的氮、磷、钾营养残留在茎鞘中,而现代品种尤其是杂交稻,成熟期营养物质向籽粒的运转率较高。

Evolution Characteristics of Nitrogen Absorption for Mid-season Japonica Rice Cultivars

The variation regularity of nitrogen absorption in the varieties replacement is studied in this paper, the representative mid-season japonica rice in Jiangsu Province as materials. The results showed that modern cultivars had higher amount of nitrogen absorp-tion in plants at each growth stage, compared with old cultivars. The absorption and accumulated of N in plants for all types of culti-vars were mainly in the period from jointing to heading stage, and the proportions of the nutrients absorbed during this period to the total absorption during the whole growth period were increased with the evolution of the cultivars. Old cultivars had higher amount of nutrients in stems and sheaths at maturity than that of modern varieties. Modern cultivars, especially hybrid combinations, exhibited a high translocation percentage of nutrients from vegetative organs to grains during the grain filling period.