Tissue level distribution of toxic and essential elements during the germination stage of corn seeds (Zea mays, L.) using LA-ICP-MS
Tissue level distribution of toxic and essential elements during the germination stage of corn seeds (Zea mays, L.) using LA-ICP-MS
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使用 LA-ICP-MS 分析玉米种子 (Zea mays, L.) 发芽阶段有毒元素和必需元素的组织水平分布
DOI：
10.1016/j.envpol.2019.05.129
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发表时间：
2019
影响因子：
8.9
通讯作者：
Wu, Fengchang
中科院分区：
文献类型：
--
作者：
Gaiss, Shelby;Amarasiriwardena, Dulasiri;Alexander, David;Wu, Fengchang
必需的和有毒的金属污染物都通过在植物中的生物积累来影响农作物。本研究的目的是评价金属(类)在玉米种子中的组织水平空间分布。他们从湖南锡矿山锑矿附近受污染的玉米地采集了一份研究报告，并将其与马萨诸塞州阿默斯特一个农场种植的玉米(玉米、爆米花)进行了比较，作为对照，该农场实行了可持续农业。还研究了有毒和必需金属如何在萌发的早期阶段通过根和地上部转运。清洗后的玉米种子样品被固定在树脂块中，并纵向解剖成薄片。对激光消融参数进行了优化，并使用番茄叶标准物质(NIST SRM 1573a)对仪器进行了颗粒定标。采用电感耦合等离子体质谱(LA-ICP-MS)测定了玉米种子中砷、镉、汞、锑、锌等金属元素(Loid)S的组织水平分布。对对照农场的种子进行萌发，并对其根和地上部进行分析，以确定组织水平浓度及其空间分布。研究发现，中国新科斯矿区的种子由于从污染的矿区土壤中吸收了金属(固体)而具有较高的所有被分析元素的总浓度。与玉米种子的胚乳相比，胚芽(∼360 mg/kg)和果皮(∼0.48 mg/kg)中的金属类物质含量最高。必需元素锌存在于胚芽、萌发的胚芽鞘和胚根中。最后，在根和枝条中，元素浓度在顶端近端比远端浓度最高，然后转移到远端组织区域。这项研究提供了关于金属(Loid)在玉米中的生物积累和转移的独特见解，因此能够更好地跟踪金属(Loid)污染物在我们的食品系统中的运输。
Both essential and toxic metal contaminants impact agricultural crops by bioaccumulation in plants. The goal of this study was to evaluate the tissue-level spatial distribution of metal(loids) in corn seeds (Zea mays,L.) from contaminated corn fields near the Xikuangshan (XKS) antimony mine in Hunan, China, and compared them with corn (Zea mays evertaL., popcorn) grown in a farm in Amherst, MA that practices sustainable farming as a control. How toxic and essential metals translocate through the roots and shoots during early stages of germination was also investigated. The cleaned corn seed samples were mounted in resin blocks and longitudinally dissected into thin sections. The laser ablation parameters were optimized, and the instrument was calibrated using tomato leaf standard reference material (NIST SRM 1573a) in a pellet form. Tissue level distributions of metal(loid)s As, Cd, Hg, Sb and Zn in corn seeds collected were determined using (LA-ICP-MS). Seeds from the control farm were germinated and their roots and shoots were analyzed to determine tissue level concentrations and their spatial distributions. It was found that seeds from the XKS mine region in China had higher overall concentration of all elements analyzed due to metal(loids) absorbed from contaminated mine soils. Metal(loids) concentrations were highest in the embryo (∼360 mg/kg) and pericarp (∼0.48 mg/kg) compared with the endosperm of corn seeds. Essential element Zn was found in the embryo and emerging coleoptile and radicle. Finally, in both roots and shoots, element concentrations were highest proximally to the tip cap compared to distal concentrations and later translocated to distal tissue regions. This study offers unique insights of metal(loid) bioaccumulation and translocation in corn and thus is better able to track metal(loids) contaminants trafficking in our food systems.