Mineral-element transport into and distribution in seeds

增加主粮作物的微量营养素密度被认为是克服营养不良的最有效方法，特别是在发展中国家。然而，生物强化策略的主要限制是对控制植物中微量营养素运输、装载和在籽粒内分布的相关生理和分子过程的理解不足。这就需要能够在种子中微量定位矿物质元素的分析工具。在为数不多的可能的分析方法中，激光烧蚀电感耦合等离子体质谱（LA-ICP-MS）迄今尚未应用。假设LA-ICP-MS提供了一个有价值的工具，不仅可以提高我们对种子中金属分布的基因型差异的了解，还可以利用稳定同位素了解金属在种子中的转运。两个具体的假设将被实验解决：(i)使用适当的时间供应，结合形式，并与N和S化合物的结合，可以改变种子中微量营养素金属的浓度，特别是分布，以达到在胚乳中的高浓度。有益和不利的重金属通常在种子中共同定位，但更好地了解种子内的空间分布将有助于设计解开这种关系的策略，以便能够单独集中目标金属。

Increasing the micronutrient density in staple food crops is regarded as a most effective way of overcoming malnutrition, particularly in the developing world. However, the major limitation to biofortification strategies is a poor understanding of relevant physiological and molecular processes controlling micronutrient transport in plants, loading into and distribution within grains. This requires analytical tools capable of micro-localising mineral elements in seeds. Among the few possible analytical approaches to the task, Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) has not been applied so far. It is hypothesised that LA-ICP-MS provides a valuable tool to enhance our knowledge not only on genotypic differences in metal distribution in seeds but also on metal transport into and in the seeds using stable isotopes. The two specific hypotheses to be experimentally addressed are: (i) using the proper timing of the supply, binding form, and association with N and S compounds, the concentration and particularly the distribution of the micronutrient metals in the seeds can be altered to achieve a high concentration in the endosperm. (ii) Beneficial and unfavourable heavy metals are normally co-localized in seeds, but a better knowledge of the spatial distribution within the seeds will allow designing strategies for untying this relationship so that targeted metals can be concentrated individually.