Abstract:

【Objective】 The objective of this experiment is to clarify the characteristics of zinc (Zn) absorption, accumulation and distribution in high-yielding winter wheat (with a grain yield 9 000 kg•hm-2). 【Method】 Field experiments were conducted in Gaocheng County, Hebei Province. Four winter wheat cultivars, Shimai 14, Jifeng 703, Shimai 12 and Shixin 828 during 2004-2005, and four cultivars, Temai 1, Shimai 12, Shixin 531 and Shixin 828 during 2005-2006, were used as experimental materials. Plant samples were collected from the plots at each growing stage for Zn concentration determination. 【Result】 The main results showed that the concentration of Zn in various above-ground organs of wheat was 9.5-112.5 mg•kg-1 at different growing stages. The organ with the highest Zn concentration changed with the growth center at different growing stages. The accumulation amount of Zn in leaf blades was the highest among all organs during early growing period, and the distribution percentage of Zn in leaf blades was more than 50% before jointing stage, higher than those in other organs. In late growing period, however, the accumulation amount of Zn in grains was the highest, and the distribution percentage of Zn in grains was 58.1% at maturity. The total accumulation amount of Zn in wheat plants during its life span ranged from 384.9 to 475.9 g•hm-2. The amount of Zn required for the formation of 100 kg grain yield ranged from 4.3 to 5.2 g. The net absorption, transportation of Zn and the contribution of all organs to grain Zn were all in the order of leaf blades ＞ spikes ＞ leaf sheaths ＞ stems. 58.2%-60.3% of Zn in grains was redistributed from other organs, especially from leaves.【Conclusion】 The concentration and accumulation of Zn in all organs of wheat was high during early and middle growing periods, and the accumulation of Zn in grains during late growing period mainly depended on the redistribution from various organs. According to the characteristics of Zn absorption and accumulation, Zn should be applied as seed dressing or basal dressing, so as to accelerate the early growth and zinc absorption of wheat.

Key words: winter wheat, high yield, zinc, absorption, accumulation, distribution