ABSTRACT

Silicon (Si) is classified as a beneficial element in higher plants. Although there is an abundance of literature on Si extraction and analysis in graminaceous crops such as rice and sugarcane, there is limited information on the validation of these methods for most dicotyledonous horticultural crops. These methods include gravimetric extraction, which requires a larger sample size the smaller the Si content in the test plant. A autoclave inductive digestion is considered effective by some and criticized by others due to the use of a strong oxidant and its sensitivity to the level of Si in the plant material. Microwave digestion method occurs in a closed system, which avoids contamination, is quick and results in a high recovery rate due to its high extraction temperature. The aim of this experiment was to validate Si measurement following microwave digestion using inductively coupled plasma optical emission spectrometry (ICP-OES) and molybdenum blue colorimetry. The recovery of Si additions as SiO₂ was 82%-96% by ICP-OES and 85–94% by colorimetry. The recoveries did not differ between measurement methods (P > .05) but the ICP-OES results were more consistent. The limit of detection for Si determination by means of ICP-OES and that for the spectrophotometry method were 48 µg L⁻¹ and 200 µg L⁻¹, respectively.

摘要

硅 (Si) 被归类为高等植物中的有益元素。尽管有大量关于禾本科作物（如水稻和甘蔗）Si 提取和分析的文献，但关于对大多数双子叶园艺作物验证这些方法的信息有限。这些方法包括重力提取，测试设备中的硅含量越小，则需要越大的样本量。由于使用强氧化剂及其对植物材料中 Si 水平的敏感性，高压釜感应消化被一些人认为是有效的，但也被其他人批评。微波消解方法在封闭系统中进行，避免了污染，由于其提取温度高，因此速度快且回收率高。本实验的目的是使用电感耦合等离子体发射光谱法 (ICP-OES) 和钼蓝比色法验证微波消解后的硅测量。以 SiO 形式回收 Si 添加物₂ ICP-OES 为 82%-96%，比色法为 85-94%。不同测量方法的回收率没有差异 ( P > .05)，但 ICP-OES 结果更加一致。通过ICP-OES 和分光光度法测定Si 的检测限分别为48 µg L ^-1和200 µg L ^{- 1}。