Univ Rennes, Université de Rennes 1, CNRS, ECOBIO [(Ecosystems-Biodiversity-Evolution)] - UMR 6553, Campus de Beaulieu, 263 avenue du Général Leclerc, F-35042 Rennes Cedex, France.
Univ Rennes, Université de Rennes 1, CNRS, ECOBIO [(Ecosystems-Biodiversity-Evolution)] - UMR 6553, Campus de Beaulieu, 263 avenue du Général Leclerc, F-35042 Rennes Cedex, France.
Sci Total Environ. 2019 Dec 1;694:133661. doi: 10.1016/j.scitotenv.2019.133661. Epub 2019 Jul 31.
Soil pollution by anthropogenic chemicals is a major concern for sustainability of crop production and of ecosystem functions mediated by natural plant biodiversity. The complex effects on plants are however difficult to apprehend. Plant communities of field margins, vegetative filter strips or rotational fallows are confronted with agricultural pollutants through residual soil contamination and/or through drift, run-off and leaching events that result from chemical applications. Exposure to xenobiotics and heavy metals causes biochemical, physiological and developmental effects. However, the range of doses, modalities of exposure, metabolization of contaminants into derived xenobiotics, and combinations of contaminants result in variable and multi-level effects. Understanding these complex plant-pollutant interactions cannot directly rely on toxicological or agronomical approaches that focus on the effects of field-rate pesticide applications. It must take into account exposure at root level, sublethal concentrations of bioactive compounds and functional biodiversity of the plant species that are affected. The present study deals with agri-environmental plant species of field margins, vegetative filter strips or rotational fallows in European agricultural landscapes. Root and shoot physiological and growth responses were compared under controlled conditions that were optimally adjusted for each plant species. Contrasted responses of growth inhibition, no adverse effect or growth enhancement depended on species, organ and nature of contaminant. However, all of the agricultural contaminants under study (pesticides, pesticide metabolites, heavy metals, polycyclic aromatic hydrocarbons) had significant effects under conditions of sublethal exposure on at least some of the plant species. The fungicide tebuconazole and polycyclic aromatic hydrocarbon fluoranthene, which gave highest levels of responses, induced both activation or inhibition effects, in different plant species or in different organs of the same plant species. These complex effects are discussed in terms of dynamics of agri-environmental plants and of ecological consequences of differential root-shoot growth under conditions of soil contamination.
人为化学物质对土壤的污染是作物生产可持续性和受自然植物生物多样性调节的生态系统功能的主要关注点。然而，这些污染物对植物的复杂影响却难以理解。农田边缘、植被过滤带或轮作休耕区的植物群落通过残留土壤污染以及由于化学物质应用而产生的漂移、径流和淋溶事件，面临着农业污染物的影响。外来生物和重金属的暴露会导致生化、生理和发育效应。然而，暴露剂量、暴露方式、污染物代谢为衍生外来生物以及污染物的组合，导致了不同的、多层次的影响。理解这些复杂的植物-污染物相互作用不能直接依赖于侧重于田间施药剂量的毒理学或农艺学方法。它必须考虑到根部暴露、生物活性化合物的亚致死浓度以及受影响植物物种的功能生物多样性。本研究涉及欧洲农业景观中农田边缘、植被过滤带或轮作休耕的农业环境植物物种。在为每种植物物种最佳调整的受控条件下，比较了根和茎的生理和生长反应。受抑制生长、无不利影响或生长增强的对比反应取决于物种、器官和污染物的性质。然而，在所研究的所有农业污染物（农药、农药代谢物、重金属、多环芳烃）下，在亚致死暴露条件下，至少对一些植物物种产生了显著影响。杀菌剂戊唑醇和多环芳烃荧蒽，它们引起了最高水平的反应，在不同的植物物种或同一植物物种的不同器官中，诱导了激活或抑制作用。这些复杂的影响将根据农业环境植物的动态和土壤污染条件下根-茎生长的生态后果进行讨论。
