Hjorth Maibritt, Mondolot Laurence, Buatois Bruno, Andary Claude, Rapior Sylvie, Kudsk Per, Mathiassen Solvejg K, Ravn Helle W
Department of Terrestrial Ecology, National Environmental Research Institute, 25 Vejlsøvej, PO Box 314, Silkeborg, Denmark.
Pest Manag Sci. 2006 Jun;62(6):515-21. doi: 10.1002/ps.1194.
A new, easy, rapid and relatively inexpensive method using microscopy has been developed for the detection of herbicide effects in leaves of grass weed species displaying no visual signs of damage. The method has potential to be used as a tool to indicate future death of grass species due to herbicide exposure by observing phytochemical effects, i.e. early-warning effects. In the present study, Apera spica-venti (L.) Beauv., Bromus hordeaceus L., Alopecurus myosuroides Huds., Lolium perenne L. and Poa annua L. were exposed to lethal rates of four herbicides with different mode of action. The herbicides investigated were the thiocarbamate: prosulfocarb, the sulfonylurea: iodosulfuron, the aryloxyphenoxypropionate: fenoxaprop-P-ethyl and the organophosphate glyphosate. Autofluorescence of leaves was studied under a microscope using ultraviolet and blue light. The fluorescence of leaves treated to enhance flavonoids was also examined. To confirm the results, microspectrofluorometry was performed. Effects indicating future death of the grasses were observed in visually healthy leaves following treatment with prosulfocarb, glyphosate and iodosulfuron. No changes were detected following treatment with fenoxaprop-P-ethyl. After exposure to glyphosate or iodosulfuron, changes in the content of flavonoids and other compounds with a conjugation system and rigid structure and a decrease in the content of chlorophyll were detected in the leaves. Prosulfocarb treatment resulted in changes in the content of flavonoids and other compounds with a conjugation system and rigid structure and an increase in the content of chlorophyll in the leaves. The results obtained from microspectrofluorometry indicated that exposure to prosulfocarb caused a reduction in the flavonoids quercetin, naringenin and/or naringin.
一种新的、简便、快速且相对廉价的利用显微镜检测禾本科杂草叶片中除草剂效果的方法已被开发出来，这些杂草叶片没有明显的损伤迹象。该方法有潜力作为一种工具，通过观察植物化学效应，即早期预警效应，来指示禾本科杂草因接触除草剂而未来死亡的情况。在本研究中，将鼠尾看麦娘、野燕麦、黑麦草、多年生黑麦草和一年生早熟禾暴露于四种具有不同作用模式的除草剂致死率下。所研究的除草剂分别是硫代氨基甲酸盐类：丙草胺，磺酰脲类：碘磺隆，芳氧苯氧丙酸酯类：精恶唑禾草灵和有机磷类草甘膦。在显微镜下使用紫外线和蓝光研究叶片的自发荧光。还检测了经处理以增强类黄酮的叶片的荧光。为了证实结果，进行了显微分光荧光测定。在用丙草胺、草甘膦和碘磺隆处理后，在外观健康的叶片中观察到了指示禾本科杂草未来死亡的效应。用精恶唑禾草灵处理后未检测到变化。暴露于草甘膦或碘磺隆后，叶片中类黄酮和其他具有共轭体系和刚性结构的化合物含量发生变化，叶绿素含量降低。丙草胺处理导致叶片中类黄酮和其他具有共轭体系和刚性结构的化合物含量发生变化，叶绿素含量增加。显微分光荧光测定的结果表明，接触丙草胺会导致黄酮类化合物槲皮素、柚皮素和/或柚皮苷的含量降低。
