Stewart-Jones Alex, Poppy Guy M
Ecology and Evolutionary Biology Group, School of Biological Sciences, University of Southampton, Bassett Crescent East, Southampton, SO16 7PX, UK.
J Chem Ecol. 2006 Apr;32(4):845-64. doi: 10.1007/s10886-006-9039-6. Epub 2006 May 12.
Plants release volatile chemicals into their surrounding air space that can affect the physiology of neighboring plants and influence the behavior of insects. In studying these interactions, it is desirable to collect volatiles from plants that have not been excised and are growing under as natural conditions as possible. We compared a vessel of borosilicate glass and Nylon-6 or polyester [poly(ethyleneterephthalate) or PET] cooking bags for enclosing plants during collection of volatiles. A push-pull airflow system was used, and volatiles were trapped on Tenax TA and analyzed by gas chromatography after thermal desorption. Low levels of impurities were found for the glass vessel and polyester bags. Nylon bags contained higher levels and more impurities. Recoveries of standards of 10 plant volatiles were measured in static and dynamic systems. In a static air system, there was good recovery only from the glass vessel. In a dynamic system, there was generally good recovery from both the glass vessel and polyester bags. Recoveries of alpha-pinene and (Z)-jasmone were poor throughout. The former was shown to have a very low breakthrough volume on the Tenax TA adsorbent, and the latter may be strongly adsorbed on glass. All three materials were essentially transparent in the IR and visible (photosynthetic) range but with significantly different absorptions in the UV range. In a simulated dynamic entrainment in full sunlight, internal vessel temperatures were higher than ambient by up to 9.5 degrees C in the glass vessel and 7.5 degrees C in the polyester bag. Lower increases in temperature relative to ambient (<1 degrees C) were recorded when entrainments were conducted in the shade. In a field trial, the profiles of volatiles collected from an apple tree infested with rosy apple aphid using a glass vessel and a polyester bag were similar. Polyester bags are recommended as more convenient than glass vessels for the enclosure of plants during the collection of volatiles.
植物会向周围的空气空间释放挥发性化学物质，这些物质会影响邻近植物的生理机能，并对昆虫的行为产生影响。在研究这些相互作用时，最好从未被切除且尽可能在自然条件下生长的植物中收集挥发物。我们比较了用于在收集挥发物期间封闭植物的硼硅酸盐玻璃容器以及尼龙 - 6或聚酯（聚对苯二甲酸乙二酯或PET）烹饪袋。使用了推挽式气流系统，挥发物被捕集在Tenax TA上，并在热脱附后通过气相色谱法进行分析。发现玻璃容器和聚酯袋中的杂质含量较低。尼龙袋中的杂质含量较高且杂质更多。在静态和动态系统中测量了10种植物挥发物标准品的回收率。在静态空气系统中，只有从玻璃容器中才有良好的回收率。在动态系统中，玻璃容器和聚酯袋通常都有良好的回收率。α-蒎烯和（Z）-茉莉酮的回收率一直很差。前者在Tenax TA吸附剂上的穿透体积非常低，而后者可能会强烈吸附在玻璃上。所有这三种材料在红外和可见光（光合）范围内基本上是透明的，但在紫外范围内具有明显不同的吸收。在全光照下的模拟动态夹带中，玻璃容器内的温度比环境温度高9.5摄氏度，聚酯袋内的温度比环境温度高7.5摄氏度。在阴凉处进行夹带时，相对于环境温度的温度升高较低（<1摄氏度）。在田间试验中，使用玻璃容器和聚酯袋从感染玫瑰苹果蚜的苹果树上收集的挥发物谱相似。推荐使用聚酯袋，因为在收集挥发物期间封闭植物时，聚酯袋比玻璃容器更方便。
