High‐throughput sequencing technologies for plant pest diagnosis: challenges and opportunities

High‐throughput sequencing (HTS) technologies have revolutionized plant pest research and are now raising interest for plant pest diagnostics, with plant virus diagnostics at the forefront of development. However, the application of HTS in plant pest diagnostics raises important challenges that plant health regulators will have to address. Adapted infrastructures, technical guidelines and training are pivotal for further use and adoption of the HTS technologies in the phytosanitary framework.     

植保无人飞机施用农药应用研究进展及管理现状

植保无人飞机是现代植保施药机械,具有作业效率高、精准、节水省药、灵活机动和对施药人员安全等特点,然而,与传统施药方式不同,其用水量少,喷施农药浓度高,喷雾易飘移,存在潜在的应用风险。目前关于植保无人飞机施药应用研究主要集中在雾滴沉积分布、飘移影响因素和防治效果评价等领域,有关其在膳食风险、环境风险和职业暴露健康风险评估等方面研究较少,且药剂登记和管理标准法规等相对滞后。为全面了解植保无人飞机施药应用以及管理现状,本文综述了植保无人飞机施药应用、风险研究及国际航空植保农药登记管理情况,总结了我国在该领域发展潜力和管理建议,以期为我国植保无人飞机安全施用农药和登记科学管理提供参考。     

有害生物风险分析定量评估模型及其比较

全球化的进程使有害生物入侵问题日益严重,植物检疫工作备受重视。有害生物风险分析(pest risk analysis,PRA)是植物检疫的支撑技术之一,风险评估是其核心内容,定量评估模型的研究与应用成为近30年来该领域的热点。本文在收集、整理国内外PRA文献和相关信息的基础上,针对有害生物入侵风险半定量评估模型、定量评估模型及软件的发展进行了系统性的回顾和分析。同时,我们比较了主要模型和软件的特点、优势和局限性,归纳总结出了适用于不同起点的有害生物定量风险评估集成技术体系,并展望了我国有害生物风险分析技术的未来发展。本综述能够为我国生物入侵防控管理机构、推广部门、高等院校及科研单位提供重要的工作参考,对植物检疫工作具有理论和实践意义。     

实时定量PCR的原理及其在植物病理学研究中的应用

实时定量PCR(Real-time quantitative)是一种利用荧光信号实时监测每个循环的扩增产物,从而实现对模板进行定量分析的新技术。它具有快速、灵敏、精确等优点。该技术在分子诊断、分子生物学研究、动植物检疫以及食品安全检测等方面有广泛的应用。本文综述了实时定量PCR的原理、影响因素及其在植物病理学研究中的应用。     

宝鸡长青镇铅锌厂周围灰尘中铅的污染水平与健康风险

利用X-Ray荧光光谱仪,在宝鸡长青镇铅锌厂周围对灰尘中铅含量测试的基础上,采用污染指数及健康风险评价方法,对灰尘中铅的污染状况及健康风险进行分析。结果显示：宝鸡市长青镇铅锌厂周围灰尘中铅的平均含量为2 631.13 mg/kg,显著高于文献报道的其他城市街尘中铅的含量及陕西土壤背景值。污染指数评价结果表明,铅锌厂周围...     

The flexible scope of accreditation in GMO testing and its applicability to plant pathogen diagnostics1

Accreditation, as the formal recognition of a laboratory's competence, is increasingly important in the field of plant pathogen diagnostics. As it is necessary to consider the scope of accreditation this paper presents the main differences between the fixed and flexible scope of accreditation and discusses the applicability of the flexible scope to plant pathogen diagnostics. This assessment is supported by practical experience gained during the testing of genetically modified organisms (GMOs) according to standard ISO/IEC 17025, starting with the fixed scope in 2003 and proceeding to the partially flexible scope in 2006. With increasing flexibility, more responsibility is transferred to the laboratory during this process and procedures governing validations need to be clearly specified. Our processes of planning, performing, documenting, and evaluating results of in‐house method validations are general and applicable to the validation of different methods. They are presented here with the example of real‐time PCR validation, a method that is increasingly used in plant pathogen diagnostics due to its reliability and high sensitivity.     

An operational risk assessment framework for a plant health diagnostic laboratory

The establishment of an operational risk assessment framework (ORAF) for effective management of risks is vital to any organization. An ORAF at the Ministry for Primary Industries (MPI) Plant Health and Environment Laboratory (PHEL), Auckland, New Zealand has identified the key risks in the laboratory operations and methods for mitigating and managing these risks. Ultimately, clear accountabilities have been set for risk management so that PHEL can maximize its ability to meet its strategic objectives and the wider goals of MPI. In addition, this framework provides an opportunity to affirm the effectiveness of the existing business process and continuously builds upon it to address gaps and also centralizes risk management information for staff. This study presents the steps that PHEL has undertaken to develop, implement and enhance its ORAF. The potential risks faced by plant diagnostic laboratories, planning of staff resources and development of the tools required to undertake risk assessment activities are included. This study also explains how the laboratory implements treatment plans, mitigates risk events and monitors and maintains the framework. Finally, this study explains some of the challenges faced by PHEL during the establishment of the ORAF.     

@RISK在有害生物定量风险评估中的应用

定性风险评估和定量风险评估是有害生物风险分析的主要方法,@RISK是进行定量风险评估的重要软件工具之一。本文在回顾有害生物定性风险评估与定量风险评估概念、关系及优缺点的基础上,综合分析了国内外使用@RISK软件针对植物病原物和害虫进行定量风险评估的发展现状,并就@RISK的未来应用提出了相关建议。     

Aiming at decision making in plant disease protection and phenotyping by the use of optical sensors

Protection of crops against plant diseases is crucial in crop production. Agricultural practice and scientific research is confronted with new challenges. Environmentally friendly and sustainable solutions are increasingly demanded. Therefore, the precise detection of primary infection sites and disease dynamics is fundamental to make a decision for a subsequent management practice. In this context, optical sensors can provide an accurate and objective detection of plant diseases. This has awoken the interest and expectation from the public, farmers, and companies for sophisticated optical sensors in agriculture, providing promising solutions. Nevertheless, the application of optical sensors in a practical context in the field is still challenging, and sophisticated data analysis methods have to be developed. In general, the entire system pipeline, consisting of the type of sensor, the platform carrying the sensor, and the decision making process by data analysis has to be tailored to the specific problem. Here, we briefly recount the possibilities and challenges using optical sensors in research and practice for plant disease protection. Optical sensor-based approaches are considered as a key element in plant phenotyping. This overview addresses mainly hyperspectral imaging as it determines several plant parameters that represent the basis for more specific sensors in the future.     

Recent developments in pathogen detection arrays: implications for fungal plant pathogens and use in practice

ABSTRACT The failure to adequately identify plant pathogens from culture-based morphological techniques has led to the development of culture-independent molecular approaches. Increasingly, diagnostic laboratories are pursuing fast routine methods that provide reliable identification, sensitive detection, and accurate quantification of plant pathogens. In addition, since plants or parts thereof can be infected by multiple pathogens, multiplex assays that can detect and quantify different pathogens simultaneously are highly desirable. Technologies that can meet these requirements, especially those involving polymerase chain reaction, are being developed and implemented in horticultural and agricultural practice. Currently, DNA array technology is the most suitable technique for multiplex detection of plant pathogens. Recently, a quantitative aspect was added to this technology, making DNA arrays highly attractive for various research and practical applications. Here, we review the most important recent advances in molecular plant pathogen diagnostics, with special attention to fungal molecular diagnostics. In addition to their applicability in practice, the different criteria that have to be fulfilled for developing robust detection procedures that can routinely be used by diagnostic laboratories are discussed.     

Exposure assessment for terrestrial non-target arthropods

Concerns regarding the potential of pesticides to harm terrestrial non-target arthropod populations have led to the increased use of ecotoxicological test systems for terrestrial Non-target Arthropod risk assessment. Whilst some useful guidance on terrestrial invertebrate test systems is available, there are significant gaps in guidance for terrestrial non-target arthropod exposure estimates. The typical exposure in the standard test systems is by application of the test substance at the field rate (i. e. gram substance per hectare field) on to a two dimensional surface. However, under field conditions such a spray deposit will be diluted over the total available 3-Dimensional plant and soil surface. The recommendation is to use published leaf area index and crop interception values to standardize terrestrial dilution factors, which can then be used to predict exposure on a 3-Dimensional plant surface. Based on average crop/time specific LAI data for 26 crops, a surrogate off-crop dilution factor of 12 was calculated which can be used to convert 2-Dimensional spray drift exposure to 3-Dimensional off-crop plant surface exposure. Another significant terrestrial exposure guidance gap is how to calculate predicted environmental concentrations (PECs) for multiple application products. Based on spray interval and half-life data from 32 representative multiple application plant protection products, the typical worst-case PECs for accumulation of residues were calculated after up to 8 applications. These data showed that Multiple Application Factors (MAFs = accumulated PEC/initial PEC), increased from 1 to 3.5 after 1 to 8 applications, respectively. Finally, overall 90^th percentile spray deposit values have been proposed for deriving off-crop multiple applications PECs (1 to 8 applications) based on published spray drift data. The recommended equations for terrestrial exposure assessment include the use of:-application rate, the 90^th percentile drift value, the multiple application factors (MAF) and the standard dilution factor (for 3-Dimensional plant surface). This proposed terrestrial non-target arthropod exposure scheme is comparable with other first tier exposure assessment schemes eg aquatic exposure assessment.     

Exposure assessment for terrestrial non-target arthropods

Concerns regarding the potential of pesticides to harm terrestrial non-target arthropod populations have led to the increased use of ecotoxicological test systems for terrestrial Non-target Arthropod risk assessment. Whilst some useful guidance on terrestrial invertebrate test systems is available, there are significant gaps in guidance for terrestrial non-target arthropod exposure estimates. The typical exposure in the standard test systems is by application of the test substance at the field rate (i. e. gram substance per hectare field) on to a two dimensional surface. However, under field conditions such a spray deposit will be diluted over the total available 3-Dimensional plant and soil surface. The recommendation is to use published leaf area index and crop interception values to standardize terrestrial dilution factors, which can then be used to predict exposure on a 3-Dimensional plant surface. Based on average crop/time specific LAI data for 26 crops, a surrogate off-crop dilution factor of 12 was calculated which can be used to convert 2-Dimensional spray drift exposure to 3-Dimensional off-crop plant surface exposure. Another significant terrestrial exposure guidance gap is how to calculate predicted environmental concentrations (PECs) for multiple application products. Based on spray interval and half-life data from 32 representative multiple application plant protection products, the typical worst-case PECs for accumulation of residues were calculated after up to 8 applications. These data showed that Multiple Application Factors (MAFs = accumulated PEC/initial PEC), increased from 1 to 3.5 after 1 to 8 applications, respectively. Finally, overall 90^th percentile spray deposit values have been proposed for deriving off-crop multiple applications PECs (1 to 8 applications) based on published spray drift data. The recommended equations for terrestrial exposure assessment include the use of:-application rate, the 90^th percentile drift value, the multiple application factors (MAF) and the standard dilution factor (for 3-Dimensional plant surface). This proposed terrestrial non-target arthropod exposure scheme is comparable with other first tier exposure assessment schemes eg aquatic exposure assessment.     

Risk assessment of thiacloprid and its chemical decontamination on eggplant,Solanum melongena L.

BACKGROUND: Thiacloprid [(Z)‐3‐(6‐chloro‐3‐pyridylmethyl)‐1,3‐thiazolidin‐2‐ylidenecyanamide; Calypso^?] is a systemic insecticide having persistence in the plant system. It was chosen for the management of the eggplant shoot and fruit borer, Leucinodes orbonalis Guen. Management of this insect pest is difficult because it harbours inside the shoot and fruit portions of eggplant. The persistence of thiacloprid on eggplant has not been studied in India. The Food and Agriculture Organisation (FAO) has proposed its maximum residue limit (MRL) on eggplant as 0.7 mg kg^?1, and there is a need to validate this value. Since residues were found to be above this level, five different decontamination agents were tested for the decontamination of thiacloprid from eggplant. RESULTS: The half‐life of thiacloprid was 11.1 and 11.6 days from trials in 2 years. Safety factors such as theoretical maximum daily intake (TMDI) and maximum permissible intake (MPI) were used to arrive at a risk assessment to human health from the analytical data obtained from the field trials. Thiacloprid at the doses tested (30 and 60 g AI ha^?1) was not effective in managing eggplant fruit borer. A waiting period of 3 days before harvest of the fruits after insecticide application and a processing factor (PF) could not ensure a sufficient margin of safety (MOS). Subjecting the data to a processing factor of 60% could not bring the residues below the proposed MRL. CONCLUSION: Thiacloprid is not found to be an appropriate and effective agent for application to eggplant. Either the proposed MRL needs to be revised or good agricultural practice involving thiacloprid for plant protection in eggplant cultivation is required. Copyright © 2008 Society of Chemical Industry     

Requirements for safeguarding the health of applicators of plant protection products - an overview1

For the purpose of preventive health protection, specific instructions for applicator protection are required in the directions for use of plant protection products. A risk assessment for applicators is obligatorily made before the specific instructions are selected. The principle of the German model, the steps of risk asscssinent. and the consequent derivation of specitic instructions for health protection are presented.     

斑地锦(Euphorbia maculata)入侵特征、地理分布和风险评估

通过对文献和资料的整理,在了解斑地锦生物学和生态学特性、历史和地理分布、扩散模式等的基础上,采用2种风险评估体系,即澳大利亚(或新西兰)风险评估体系(WRA)和中欧风险评估体系(WGWRA)对其入侵风险进行评估。斑地锦原产于北美洲,最早于20世纪40年代在我国东南沿海地区发现归化;目前,已在我国25省70市有分布,并呈现随时间推移不断扩大其分布区的趋势。斑地锦为大戟科有毒植物,种子产量大、耐逆性强,适应多种多样的气候环境,可以在农田、草坪、道旁及荒地等多种生境中建植和归化。一旦入侵成功,则威胁到当地的生态安全和生物多样性。风险评估结果表明,WG-WRA分值为22分,入侵等级为中等风险Ⅱ;WRA风险评估分值为29分,具有很高的入侵风险;其中,农业和环境方面的分值分别为16分和15分。2个风险评估都表明斑地锦在我国有较高的入侵风险,是需要引起警示的外来植物。因此,必须加强对于斑地锦的预报和监测,并做好相应的防控工作。     

中国主要蜜源作物上登记的农药品种及其中杀虫剂对蜜蜂的初级风险评估

对目前中国主要蜜源作物上登记的农药品种进行了梳理,并采用现有的风险评估标准方法,对其中毒死蜱、吡虫啉等共61种杀虫剂对蜜蜂的风险进行了初级评估。结果表明:在58种喷雾施用的杀虫剂中,35种对蜜蜂的风险商值均大于1,风险为不可接受;其余23种的风险商值小于1,风险为可接受;所评估的6种土壤或种子处理内吸性杀虫剂中,5种对蜜蜂的风险商值大于1,风险为不可接受,仅氯虫苯甲酰胺的风险商值小于1,风险为可接受。但由于文中是以药剂在所登记作物上的单次最高施药剂量为暴露量进行的初级评估,并未考虑农药在花粉、花蜜中的降解及降雨引起的淋洗损耗,以及施药时间与作物花期之间的关系等影响因素,因而使得评估结果具有较大的保守性。研究结果一方面可为这些农药的合理使用和管理提供参考,另一方面提示了目前中国关于农药对蜜蜂的初级风险评估程序需进一步优化。     

高通量测序技术在植物及昆虫病毒检测中的应用

在过去的十几年中,测序技术的发展为分子生物学领域带来了革命性的变化。第二代测序(next-generation sequencing,NGS)技术以快速、高灵敏性、高通量、非序列依赖性等特点极大地促进了病毒诊断学研究领域的发展。NGS技术可以在不了解病毒的生物学特性、血清学特点及基因组信息情况下快速检测未知病毒。通过对总核酸样本进行NGS可以获得某个特定生态环境或种植系统中的所有病毒序列,即病毒组。通过大量的NGS数据可以分析寄主中某一病毒的基因组变化、构建病毒的准种以及研究病毒的进化和起源。本文介绍了高通量测序的方法在植物和昆虫病毒检测中的应用。     

Pest risk analysis for Solanum elaeagnifolium and international management measures proposed

Solanum elaeagnifolium Cav., originating from the Americas, has been unintentionally introduced in all the other continents as a contaminant of commodities, and is considered one of the most invasive plants worldwide. In the Euro‐Mediterranean area, it is a huge threat in North African countries. It is also present in European Mediterranean countries (France, Greece, Italy and Spain), but still has a limited distribution. Through a logical sequence of questions, pest risk analysis (PRA) assessed the probability of S. elaeagnifolium entering, establishing, spreading and having negative impacts in European and Mediterranean countries. As this assessment revealed that the entry of the pest would result in an unacceptable risk, pest risk management options were selected to prevent the introduction of the plant. Preventive measures on plants or plant products traded internationally may directly or indirectly affect international trade. According to international treaties, PRA is a technical justification of such international preventive measures.