Collaborative Research: The Role of Plants in the Environmental Fate of Growth Promoters and Antibiotics Used in Concentrated Animal Feed Operations

提案题目：合作研究：植物在动物浓缩饲料生产中使用的生长促进剂和抗生素的环境命运中的作用院校：俄亥俄州立大学；申请号：CBET-0965863；集中的动物饲料操作（CAFO）废物和土地应用中使用的其他来源的动物粪便含有激素（天然和管理），模拟激素活性的合成物质和抗生素。这些物质可以随径流进入地表水，并可能对水生生态系统产生有害影响，例如在极低浓度（ng/L）下使本地鱼类雌性化。虽然微生物降解已被证明是主要的降解途径，但其中一些物质在使用CAFO废物后可以持续数月。植物的吸收和净化可能是一种经济有效的方法，可以拦截这些废物中的激素、它们的合成类似物和抗生素，这些废物已通过使用沿地表水道的河岸缓冲带应用于农田。此外，有证据表明，植物和土壤的吸收也可以阻止这些物质进入地下水。在这项提案中，pi希望研究经济作物植物是否可以转化这些化合物或仅仅积累它们。他们将测试以下假设：(1)激素（合成类似物和天然的）和抗生素可以根据这些物质的物理化学性质被植物吸收；(2)植物既能积累这些物质，又能将其转化为良性衍生物；(3)植物吸收和降解是土壤自然衰减的补充，两者结合是被动处理这些物质的有效手段。为了验证这些假设，他们将研究植物对17<s:1> -雌二醇及其代谢物雌酮、zeranol（一种非激素生长促进剂）和tylosin（一种抗生素）的吸收和降解情况。杂交杨树，一种可以理想地用于河岸缓冲的树；还有箭根，一种原生的非入侵水生植物。他们将评估1)目标化合物的吸收/解吸特性以及这一过程将如何影响它们对植物的生物利用度，2)转化是否在植物中发生，3)化合物及其代谢物在植物组织中的积累位置，以及4)土壤和根际微生物群落在这些化合物的整体降解中的作用。从CAFO废物中释放到地表水中的激素、它们的合成类似物和其他药物对水生生态系统构成威胁。尽管自然衰减可以降解其中的许多化合物，但在土地施用数月后，粪肥仍然可以滤出这些物质，对水生生物造成危害。植物的吸收和降解与天然微生物的降解相辅相成，两者结合可将CAFO废物中这些物质的浓度降低到较低的有害水平。建议的工作将支持两名学生的研究生教育。pi还积极向科学界和广大公众传播这些信息。其中包括包括K-12学生、私家侦探和他们的研究小组在内的积极项目。最后，他们将与各自的大学推广项目协调努力，帮助农业社区处理农业废弃物。

Proposal Title: Collaborative Research: The Role of Plants in the Environmental Fate of Growth Promoters and Antibiotics Used in Concentrated Animal Feed OperationsPrincipal Investigators: Chin, Yu-Ping; Schnoor, JeraldInstitutions: Ohio State University; University of IowaProposal No: CBET-0965863; CBET-0966683Concentrated animal feed operation (CAFO) waste and other sources of animal manure used in land applications contain hormones (natural and administered), synthetic substances that mimic hormonal activity, and antibiotics. These substances can enter surface waters with runoff and may have deleterious effects on aquatic ecosystem such as the feminization of native fish at exceedingly low concentrations (ng/L). While microbial degradation has been documented to occur and is believed to be the primary degradation pathway, some of these substances can persist for months after the application of CAFO waste. Uptake and depuration by plants may be a cost effective means to intercept hormones, their synthetic analogs, and antibiotics in these wastes that have been applied to croplands through the use of riparian buffer strips along surface waterways. Further, evidence show that plants and sorption to soils can also prevent the introduction of these substances to groundwater. In this proposal the PIs wish to examine whether economic crop plants can transform these compounds or merely accumulate them. They will test the hypotheses that: (1) hormones (synthetic analogs and natural) and antibiotics can be taken up by plants based upon the physicochemical properties of these substances; (2) plants can both accumulate and transform these substances to benign derivatives; and (3) plant uptake and degradation complement natural attenuation in soils and in combination are an effective means to passively treat these substances.To test these hypotheses, they will examine the plant uptake and degradation of 17â-estradiol, its metabolite estrone, zeranol (a non-hormone growth promoter), and tylosin (an antibiotic) using soybean plants, a row crop plant; hybrid poplars, a tree that can be ideally used in riparian buffers; and arrow root, a native non-invasive aquatic plant. They will assess 1) sorption/desorption characteristics of the target compounds and how this process will affect their bioavailability to the plants, 2) whether transformation occurs in the plants, 3) where the compounds and their metabolites accumulate in plant tissues, and 4) the role of microbial communities in soils and the rhizosphere in the overall degradation of these compounds.Hormones, their synthetic analogs, and other pharmaceuticals released to surface waters from CAFO waste pose a threat to aquatic ecosystems. Even though natural attenuation can degrade many of these compounds, manure fertilizer can still leach these substances at levels that can harm aquatic organisms months after land application. Plant uptake and degradation complements native microbial degradation and in combination may reduce the concentration of these substances in CAFO waste to less harmful levels. The proposed work will support the graduate education of two students. The PIs are also active in disseminating this information to both the scientific community and the public at large. These include active programs involving K-12 students, the P.I.s, and their research groups. Finally, they will coordinate their efforts with their respective university extension programs to help farm communities cope with agricultural waste.