The Dutch approach: a combination of meteo‐based decision‐support systems*

Reduction in the amount of active substance and reduced dependence on chemical plant production products are the main items in the Dutch Government Multiyear Crop Protection Plan. There are problems in reaching this goal, as weather conditions in The Netherlands are very beneficial to all kinds of fungal diseases. Such diseases have to be controlled by applications of preventive fungicides, and it is quite regular to use a spray interval of 6–7 days. Another problem is application at the wrong time. With the help of decision‐support systems (DSSs), it is possible to calculate the period of protection by a product, the danger of an infection period and the moment of highest efficacy. DLV‐Meteo offers advice based on five DSSs for individual pests (Prophy, onion leaf spot disease, Botrypré, Mycos and Contapré) and on a general DSS for application at the time of day that ensures highest efficacy (Gewis).     

A comparison of crop and non-crop plants as sensitive indicator species for regulatory testing

The effectiveness of regulatory non-target plant testing using crop species to predict the phytotoxicicity of herbicides to non-crop species was evaluated for eleven herbicides. These herbicides were representative of eight chemical classes and six modes of action. Data for non-crop plants from pre-emergence and post-emergence efficacy screening studies were compared with those for the most sensitive crop species defined by regulatory tests conducted to meet US EPA requirements. Testing under pre-emergence conditions for ten compounds indicated that for five of the compounds (K-815910, trifluralin, pyridyloxy A, pyridyloxy B and cyanazine), the most sensitive crop species was more sensitive than all the non-crop species evaluated. For metsulfuron-methyl, chlorimuron-ethyl, hexazinone and bromacil, only one of the non-crop species evaluated was more sensitive than the most sensitive crop species from regulatory tests. Data for the tenth compound, chloroacetamide, showed that four of 32 non-crop species tested in efficacy screens had at least one rate at which greater visual effects were observed than were observed for the most sensitive crop response in a regulatory test. The results of post-emergence exposure comparisons for five of the compounds (pyridyloxy A, cloransulam-methyl, chlorimuron-ethyl, cyanazine and hexazinone) indicated that the most sensitive crop species were more sensitive than all the non-crop species evaluated. Data for pyridyloxy B, metsulfuron-methyl and bromacil indicated that only one of the non-crop species evaluated was more sensitive than the most sensitive crop species. For trifluralin, three of the eight non-crop species were more sensitive than the most sensitive crop species. Data for K-815910 indicated that four of the fourteen non-crop species tested were marginally more sensitive than the most sensitive crop, but were within the same range of sensitivity. These results indicate that the current regulatory test batteries and methods using crop species effectively provide suitable sensitive indicator plants for the eleven diverse herbicides evaluated. This comparison indicates that crop species sensitivity to test substances is likely to be representative of non-crop herbaceous species response, regardless of chemical class, mode of action and magnitude or route of exposure.     

Sugar concentration in nectar: a quantitative metric of crop attractiveness for refined pollinator risk assessments

Those involved with pollinator risk assessment know that agricultural crops vary in attractiveness to bees. Intuitively, this means that exposure to agricultural pesticides is likely greatest for attractive plants and lowest for unattractive plants. While crop attractiveness in the risk assessment process has been qualitatively remarked on by some authorities, absent is direction on how to refine the process with quantitative metrics of attractiveness. At a high level, attractiveness of crops to bees appears to depend on several key variables, including but not limited to: floral, olfactory, visual and tactile cues; seasonal availability; physical and behavioral characteristics of the bee; plant and nectar rewards. Notwithstanding the complexities and interactions among these variables, sugar content in nectar stands out as a suitable quantitative metric by which to refine pollinator risk assessments for attractiveness. Provided herein is a proposed way to use sugar nectar concentration to adjust the exposure parameter (with what is called a crop attractiveness factor) in the calculation of risk quotients in order to derive crop‐specific tier I assessments. This Perspective is meant to invite discussion on incorporating such changes in the risk assessment process. © 2016 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

广西大石山区农业干旱灾害综合风险管理战略

伴随着我国干旱灾害管理从危机模式到综合风险模式的转变,以广西大石山岩溶区为研究对象,在对该区近20年农业干旱灾害调查分析的基础上,采用模糊信息扩散方法对该区26个县农业干旱风险进行了评估。研究结果表明:广西大石山区近20年来平均每2年至少会发生农业干旱1次,且强度呈逐渐增加的变化趋势;该区平均发生轻度、中度、重度和特大农业干旱灾害的频次分别为1.3年/次、2.2年/次、6.3年/次、15.3年/次。根据区域干旱灾害风险模型:区域干旱灾害风险=(危险性H×暴露性E×脆弱性V)/抗旱减灾能力C,加强该区抗旱减灾能力建设是有效应对日益复杂的干旱灾害和减轻灾害风险最有效的途径和手段。广西大石山区应开展具有可操作性的干旱防备与应对系统以实现该区干旱灾害综合风险管理战略的实施。     

GEWIS,a weather‐based decision support system for timing the application of plant protection products*

Weather circumstances before, during and after the application of plant protection products are very important for efficacy. Knowledge of the behaviour of products in relation to weather circumstances can be an aid to achieving better efficacy and even serve as a tool for reducing the dose in well‐defined applications. Formulation type and dynamic build‐up of the wax layer on the upper side of the leaf are important for sticking and the speed and method of uptake of active substances into the leaves. It is difficult for farmers to combine all the important processes. Knowledge of the relations between plant protection products and meteorological conditions is combined in a decision support system (DSS) with the acronym GEWIS. The system calculates (hourly based) the physical behaviour of products at different stages in the process. With the help of this DSS, the farmer can choose the best moment of the day to apply a product with the optimum dose. Furthermore, users learn when it is possible to apply lower dosages and when not to apply at all.     

基于点评估方法的渤海湾产区苹果中农药残留膳食暴露风险研究

为评估渤海湾产区苹果中主要农药的残留情况及其产生的风险,在山东、辽宁及河北3个主要省份的150个生产基地进行了苹果样品采集与测定分析,并对我国不同人群的膳食暴露风险进行了评估。结果表明:93.3%的苹果样品检出有低浓度农药残留,经最大残留限量值(MRL)判定后100%合格,82.0%的样品中农药残留种类在3种及以下;共检出17种农药残留,大多为低毒或无毒农药,无禁用和高毒农药。采用点评估方法,选择检出率在20%以上的多菌灵、毒死蜱、啶虫脒和戊唑醇进行不同消费人群暴露点评估。结果显示:4种农药的急性和慢性摄入风险均为儿童高于成年人,绝大多数女性人群的摄入风险高于男性;4种农药急性摄入风险均高于慢性摄入风险,风险水平由高到低为多菌灵毒死蜱戊唑醇啶虫脒,但点评估结果均远低于100%,说明通过食用苹果摄入的农药残留极其微量,不会对人体产生急性或慢性风险。     

PP 1/296 (1) Principles of efficacy evaluation for low‐risk plant protection products

Specific scope

This Standard describes the principles for determining the requirements for an efficacy evaluation of low‐risk plant protection products in a registration procedure. Low‐risk plant protection products are products with low risk to human and animal health and the environment.

Specific approval and amendment

First approved in 2017‐09.     

Resistance risk assessment within herbicide authorisation – a call for sensitivity data

In most European countries, the risk of herbicide resistance is assessed as part of the authorisation of herbicides in accordance with EPPO Standard PP 1/213(2). Because the susceptibility of weed populations to a certain herbicide may vary greatly, one part of resistance risk assessment is the testing for sensitivity variation among different populations of target weed species with a high resistance risk. This paper emphasises the importance of sensitivity data provision with regard to the recent EU Regulation (EC) 1107/2009 concerning the placing of plant protection products on the market and outlines the main technical requirements for sensitivity data. A useful principle is that sensitivity data should be provided for all herbicides with a high resistance risk regardless of whether resistance has already evolved against the herbicidal substance. Methodical details regarding the generation of sensitivity data are discussed, together with remaining questions that will need to be addressed if a harmonised assessment of herbicide resistance risk is to be achieved. Copyright © 2012 Society of Chemical Industry     

Perspective: service‐based business models to incentivize the efficient use of pesticides in crop protection

Several problems limit the productivity and acceptance of crop protection, including pesticide overuse, pesticide resistance, poor adoption of integrated pest management (IPM), declining funding for research and extension, and inefficiencies of scale. We discuss the proposition that alternative business models for crop protection can address these problems by incentivizing and benefiting from efficiency of pesticide use. Currently, business models are not linked to the adoption of IPM and are sometimes at odds with IPM practices. We explore a business model based on the provision of pest management adequacy through services rather than the sale of pesticide products. Specifically, we advocate for establishment of crop protection adequacy standards that would allow a market system to maximize efficiency. Changing some of the relationships between agricultural companies and producers from one based on products to one based on services is an idea worthy of debate and evaluation for improving the efficiency of pest management. Contemporary information technology enhancing monitoring and coordination warrants attention in this debate. © 2019 Society of Chemical Industry     

A model of the decision‐support scheme for express pest risk analysis using a Bayesian network implemented in Excel

A model was developed to accompany the EPPO decision support scheme for express pest risk analysis (PRA) and provide a calculated overall risk and uncertainty for the PRA and so act as a reference for the judgement of overall risk and uncertainty provided by expert working groups. Implemented in Excel, it is readily accessible to PRA practitioners and offers: (a) a consistent and explained weighting of the different risk factors and a rationale for the way they are combined, (b) a calculated integration of the risk factor distributions to facilitate judgement of overall uncertainty, and (c) an account of the interaction between the rating and the uncertainty score so that, for example, an overall rating of moderate is not necessarily used to reflect uncertainty about assessments in which the risk is neither obviously high nor low. Of the nine published express PRAs examined, the rating and uncertainty predicted by the model were: in agreement with five; differed in both rating and uncertainty in one case; differed in rating only in one case; and differed in uncertainty only in two cases. Possible reasons for these differences were examined and the interpretation of model results to inform assessments is discussed.     

Development of comparable agro‐climatic zones for the international exchange of data on the efficacy and crop safety of plant protection products1

Data on the efficacy and crop safety of plant protection products can be used for registration purposes in other countries, provided crop growth conditions are comparable. This article identifies the main conditions which are relevant in this respect, with particular emphasis on climatic conditions. Comparison of several systems of agro‐climatic classification developed for the EPPO region, particularly the climate diagrams of Walter & Lieth, the climate classification system of Köppen & Geiger, the agro‐climatic areas of Thran & Broekhuizen and natural vegetation maps, has led to a division of the EPPO region (Europe, Mediterranean area, Middle East) into four agro‐climatic zones (Mediterranean, Maritime, North‐east, Central) within which conditions can be considered comparable.     

Lessons from 10 years of stakeholder adoption of a soil bioassay for assessing the risk of spinach Fusarium wilt

Although the maritime Pacific Northwest (PNW) is the only region of the United States suitable climatically for spinach seed production, the acidic soils are highly conducive to spinach Fusarium wilt caused by Fusarium oxysporum f. sp. spinaciae. A soil bioassay developed to quantify the risk of spinach Fusarium wilt in fields has been offered to seed growers annually since 2010. Soil sampled from growers' fields each winter was planted with highly susceptible, moderately susceptible, and partially resistant spinach inbred lines, and the plants rated weekly to calculate a Fusarium wilt severity index (FWSI) and the area under the disease progress curve (AUDPC). Results for 147 soils tested from 2010 to 2013 have been published. This study examined results for an additional 248 soils tested from 2014 to 2019 with the bioassay modified to include an option of agricultural limestone amendment to the soils tested. FWSI and AUDPC were affected significantly (p < .001) by the main effects of soil and spinach inbred line, and the interaction of these factors. Correlation analyses showed a range in degree of association of FWSI and AUDPC with spinach seed crop rotation duration and soil properties, depending on the spinach inbred line (r = −.255 to –.267, n = 172 soils with characteristics suitable for correlation analyses). Stepwise regression models for 172 soils with relevant parameters for regression analyses identified spinach seed crop rotation interval, rate of agricultural limestone amendment, soil pH, and soil Fe, Mn, and Zn concentrations as most strongly associated with FWSI and AUDPC. However, the models accounted for ≤33.4% (R²) of the variability in Fusarium wilt risk. The soil bioassay remains a primary tool for spinach seed growers to select fields with low risk of Fusarium wilt.