Quantifying and understanding uptake of plant protection products from soil into plants

量化和了解植物保护产品从土壤到植物的吸收

• 批准号: 1642222
• 金额: --
• 依托单位: University of Reading
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2015
• 资助国家: 英国
• 起止时间: 2015 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-1642222
• 关键词: Quantifying; understanding; uptake; plant; protection

This project brings together the Product Safety Division of Syngenta and Soil Research Centre at the University of Reading to address the uptake of pesticides by plants from soil solution. The collaboration addresses issues raised at the EUregPUF workshop, York, 2013 regarding a standardized protocol for the determination of the plant uptake factor (PUF) and subject areas identified in the Syngenta call for proposals i.e. Pesticide metabolism, transport and uptake in fungi, plants and insects (inc.modelling & prediction) and Movement of chemicals in soil and uptake into roots.AimsTo establish the relationship between plant uptake in hydroponic solution against that in soil.To improve environmental fate models by quantifying field variability and streamlining model structure.ExperimentalThe project will use the protocol developed by Sweeney et al. to determine the PUF of a range of pesticides with varying physicochemical characteristics from hydroponic solution. There is some debate whether the PUF can be greater or less than 1 and whether hydroponic systems are a realistic surrogate for uptake by plants from soil. The protocol will be marginally altered in order to provide more realism i.e. sand as the substrate to improve root growth with nutrients added to ensure plant vitality.In lysimeters/small field plots selected active ingredients will be examined to measure the plant uptake and fate in soil. Soil pore water concentration will be measured both in-situ (PECAM and TECAM) and ex-situ (centrifuge technique). The measurements will be taken at a range of distances from the plant to determine the root influence across a fixed area of soil enabling an integrated value for a whole field to be determined. Data from an on-site meteorological station will be used to calculate the plant transpiration which when multiplied by the PUF determines the mass of pesticide removed by the crop.The field and laboratory values will be compared and the factors responsible for the primary differences in plant uptake identified, their variability will be recorded for the modelling phase.ModellingThere are considerable gaps to be addressed when modelling the fate of pesticides in soils. For example; model complexity is frequently not justified, the validation rarely uses an independent data set and single parameter values are used without knowledge of their variability. Frequently, models used for regulatory purposes within the EU such as PEARL and PELMO use a single parameter to represent plant uptake as a result of abstraction of water from soil to satisfy evapotranspiration demand. Such a simple approach does not take into consideration the pH of soil pore water (pH is known to affect uptake of ionisable compounds) and the split between adsorption to roots and translocation into shoots. Of particular interest are soil sorption and pesticide transformation parameters which are an order of magnitude more sensitive than water flow parameters in pesticide leaching fluxes.The project will use the existing Syngenta suite of models and determine the sensitive parameters within these. The data from the experimental studies will be used to establish the extent to which existing models of environmental fate accurately represent the observed uptake of pesticides from soil in the field. Sensitivity and uncertainty analyses will be used to improve the models.OutcomeAt the conclusion of the project Syngenta will have an independently validated system for the determination of pesticide PUFs and the robustness of these values will have been tested against field data. The latter will underpin a model validation and calibration exercise to improve Syngenta's capability to predict the fate of field applied pesticides.

该项目汇集了先正达产品安全部门和阅读大学土壤研究中心，以解决植物从土壤溶液中吸收农药的问题。此次合作旨在解决2013年约克欧洲农药吸收因子研讨会上提出的关于确定植物吸收因子（PUF）的标准化方案的问题，以及先正达征求建议书中确定的主题领域，即农药在真菌中的代谢、运输和吸收，植物和昆虫（包括建模和预测）土壤中化学物质的迁移和根系吸收.目的建立植物在水培溶液中的吸收与土壤中化学物质的迁移和根系吸收之间的关系.土壤。通过量化田间变异性和简化模型结构来改进环境归宿模型。实验该项目将使用Sweeney等人开发的协议来确定一系列具有不同物理化学特性的农药的PUF。有一些争论是否PUF可以大于或小于1，以及水培系统是否是一个现实的替代吸收植物从土壤中。该方案将略有改变，以提供更多的现实主义，即沙子作为基质，以改善根系生长，并添加营养素，以确保植物的活力。在蒸渗仪/小田间小区中，将检查选定的活性成分，以测量植物的吸收和土壤中的命运。将在现场（PECAM和TECAM）和非现场（离心技术）测量土壤孔隙水浓度。测量将在距植物一定距离的范围内进行，以确定固定土壤区域内的根系影响，从而确定整个田地的综合值。从现场气象站获得的数据将用于计算植物蒸腾作用，当乘以PUF时，确定作物去除的农药质量。将比较田间和实验室值，并确定导致植物吸收主要差异的因素，在建模阶段，将记录其变异性。在土壤中。比如说：模型的复杂性通常是不合理的，验证很少使用独立的数据集，并且在不了解其可变性的情况下使用单个参数值。通常，欧盟内部用于监管目的的模型（如PEARL和PELMO）使用单个参数来表示植物吸收，作为从土壤中提取水以满足蒸散需求的结果。这种简单的方法没有考虑到土壤孔隙水的pH值（已知pH值会影响可电离化合物的吸收）以及吸附到根部和转运到地上部之间的分离。特别令人感兴趣的是土壤吸附和农药转化参数，这些参数在农药沥滤通量方面比水流参数敏感一个数量级，本项目将使用现有的先正达模型套件，并确定其中的敏感参数。实验研究的数据将用于确定现有的环境归宿模型在多大程度上准确地代表了实地观察到的土壤中农药吸收情况。在项目结束时，先正达将拥有一个独立验证的系统，用于确定农药的多不饱和脂肪酸，并将根据实地数据测试这些值的稳健性。后者将支持模型验证和校准工作，以提高先正达预测田间施用农药的结果的能力。