关键词: 中熟粳稻, 品种更替, 氮素吸收

Abstract:

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 absorption in plants at each growth stage, compared with old cultivars. The absorption and accumulated of N in plants for all types of cultivars 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.

Key words: mid-season japonica rice, evolution of cultivars, nitrogen absorption