Palmer Lachlan J, Palmer Lyndon T, Rutzke Michael A, Graham Robin D, Stangoulis James C R
School of Biological Sciences, Flinders University, Bedford Park, South Australia, 5042, Australia.
Physiol Plant. 2014 Dec;152(4):729-37. doi: 10.1111/ppl.12211. Epub 2014 May 23.
In wheat, nutrients are transported to seeds via the phloem yet access to this vascular tissue for exudate collection and quantitative analysis of elemental composition is difficult. The purest phloem is collected through the use of aphid stylectomy with volumes of exudate collected normally in the range of 20-500 nl. In this work a new method using inductively coupled plasma mass spectroscopy (ICP-MS) was developed to measure the concentration of K, Mg, Zn and Fe in volumes of wheat (Triticum aestivum, genotype Samnyt 16) phloem as small as 15.5 nl. This improved method was used to observe changes in phloem nutrient concentration during the grain loading period. There were statistically significant increases in phloem Mg and Zn concentration and a significant decrease in K over the period from 1-2 days after anthesis (DAA) to 9-12 DAA. During this period, there was no statistically significant change in phloem Fe concentration.
在小麦中，营养物质通过韧皮部运输到种子，但要获取该维管组织以收集渗出液并对元素组成进行定量分析却很困难。最纯净的韧皮部渗出液是通过蚜虫口针切除术收集的，通常收集到的渗出液体积在20 - 500纳升范围内。在这项研究中，开发了一种使用电感耦合等离子体质谱法（ICP - MS）的新方法，用于测量低至15.5纳升的小麦（普通小麦，基因型Samnyt 16）韧皮部中钾、镁、锌和铁的浓度。这种改进的方法用于观察籽粒灌浆期韧皮部营养物质浓度的变化。从开花后1 - 2天（DAA）到9 - 12 DAA期间，韧皮部中镁和锌的浓度有统计学意义的增加，而钾的浓度显著下降。在此期间，韧皮部中铁的浓度没有统计学意义的变化。
