大田条件下水稻锌营养强化方法探究及效果评估

通过田间试验,在水稻(华粳7号)分蘖期及扬花期进行施锌处理,研究在高施锌水平下水稻各器官锌含量的变化。结果表明,水稻各器官锌含量随施锌量的增加而增加,其中茎的增幅最大,叶次之。茎、叶、穗锌含量最高可分别达到666.7、461.6、185.5mg/kg。分蘖期施锌最多可使水稻糙米锌含量提高28.7%,而扬花期施锌最多可提高142.6%。由重复试验得出,扬花期施锌可稳定提高糙米锌含量,在水稻锌营养强化能力及稳定性上,扬花期施锌优于分蘖期。通过食用经强化后的大米,居民每日锌膳食摄入量可达到中国营养学会推荐的12.5mg。本研究结果对通过土施锌肥实现水稻籽粒锌水平的提升及解决我国居民普遍存在的锌营养摄入不足的现状具有理论和实际的指导意义。

Effect Evaluation on Method of Zinc Biofortification for Rice in Paddy Field

A field experiment was conducted to characterize zinc distribution in rice during the tilling and the flowering stages under a high level of zinc fertilization. The results showed that zinc contents in rice tissues were positively correlated with the amount of zinc fertilization. Compared with CK, zinc contents in stems, leaves, and spikes reached up to 666.7, 461.6 and 185.5 mg/kg, increased by 27.4, 19.6 and 8.7 times, respectively; zinc contents increased by up to 28.7% and 142.6% in unpolished rice after zinc fertilization during the tilling and the flowering stages, respectively. A conducted duplicate test confirmed that it is better and more reliable to increase zinc content in rice by zinc fertilization during the flowering stage. By consuming the biofortified rice, daily intake of zinc by Chinese citizens can reach up to 12.5 mg standard recommended by Chinese Nutrition Society. This study provided theoretical and practical references to fortify zinc in rice grain via zinc fertilization and then improved the deficiency of daily zinc intake.