小麦生长周期的甲基汞器官分布

Methylmercury Organ Distribution in Whea(tTriticum aestivum L.)During the Growing Season

通过温室模拟,动态监测了小麦生长周期中各器官中甲基汞的浓度及总量分布的变化,探讨了小麦生长周期中,甲基汞是否在子实中富集及其过程。研究结果表明,甲基汞从土壤中经根系吸收进入小麦体内并逐步向地上部分转运。小麦生长过程中,土壤和小麦根部的甲基汞浓度随着小麦生长变化不明显,茎、叶中甲基汞浓度先上升后稳定,子实中甲基汞浓度不断上升。茎、叶在小麦生长过程中向子实输送甲基汞,甲基汞富集于小麦子实之中。研究证实了在属于陆生植物的小麦子实中存在甲基汞的富集现象。

To investigate the process of methylmercury（MeHg）accumulation in wheat seeds,a green-house study was designed,and the MeHg levels and MeHg transfer in specific organs of wheat plants during a full wheat growing season was investigated.The results suggested that MeHg in soil was first absorbed by roots and then transferred gradually to the above-ground organs.During the full wheat growing season,the MeHg level increased in the seeds,and it remained constant in the stems and leaves after a period of increase.The MeHg levels remained constant in soil and the roots during the growing season.In the flowering stage,the majority of MeHg in the wheat accumulated in the stems and leaves.MeHg was transferred to seeds from stems and leaves and eventually accumulated in its edible parts.At the end of the filling stage,about half of the MeHg accumulated in the seeds of the wheat.This study supports that MeHg accumulation in seeds exists in wheat and probably other terrestrial plants,although the accumulation mechanism of wheat for MeHg is different from aquatic plants like rice.