Lead (Pb) is the most prevalent heavy metal pollutant in the natural environment. Pb is not a fundamental element for plants, but they absorb it when it is present in their environment, having no known physiological activity. The aim of our research was to evaluate the efficacy of laser photoacoustic spectroscopy as a tool to monitor changes induced by Pb in plant respiration by highlighting two molecular markers (C2H4 and CO2). To better understand Pb phytotoxicity, we monitored the plantlets evolution as well as the morphology of the root cells. Firstly, we showed that the treatment hinders the plantlet’s development. Furthermore, using laser photoacoustic spectroscopy, we found a decrease in the concentration of C2H4 and CO2 vapors measured in the respiration of treated plants. Finally, fluorescence microscopy results showed that in Pb treated plantlets, the cell roots morphology is clearly altered as compared with the untreated ones. All the results are well correlated and can help further in understanding Pb phytotoxicity.

中文翻译：

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使用 CO2 激光光声光谱法分析种子中铅的植物毒性

铅 (Pb) 是自然环境中最普遍的重金属污染物。铅不是植物的基本元素，但当它存在于环境中时，它们会吸收它，没有已知的生理活性。我们研究的目的是通过突出两种分子标记（C2H4 和 CO2）来评估激光光声光谱作为监测植物呼吸中铅引起的变化的工具的功效。为了更好地了解 Pb 的植物毒性，我们监测了小植株的进化以及根细胞的形态。首先，我们表明处理阻碍了小植物的发育。此外，使用激光光声光谱，我们发现在处理过的植物呼吸中测量的 C2H4 和 CO2 蒸气的浓度降低。最后，荧光显微镜结果表明，与未处理的相比，Pb 处理的植株的细胞根形态发生了明显的改变。所有结果都具有良好的相关性，可以帮助进一步了解 Pb 的植物毒性。