新形势下加强农药市场监管的思考

本文从分析红河州农药执法监督和农药市场经营现状入手,结合当前农业由传统农业向现代农业转变的经济发展新常态,创新工作思路,提出整合农药监管资源,联合执法检查,建立农产品安全监管综合服务体系的思考,对保障新形势下农业生产及农产品质量安全的方式方法进行探索。     

基于点评估方法的两广地区番木瓜中农药残留膳食暴露风险研究

为评估两广地区番木瓜中主要农药的残留情况及其产生的风险,采集了广东、广西地区40个生产基地的番木瓜样品进行测试分析,研究其生产过程中使用的杀虫剂、杀菌剂、杀螨剂和植物生长调节剂等各种农药残留情况,并对我国不同人群的膳食暴露风险进行了评估。结果显示,40批次番木瓜中检出农药残留32批次;在检出的32份番木瓜样品中,检出率超过10%的有咪鲜胺、吡虫啉、多菌灵、啶虫脒和苯醚甲环唑5种农药,检出率分别为51.1%、21.5%、13.3%、11.1%、10.9%。采用点评估方法,选择检出率在10%以上的咪鲜胺、吡虫啉、多菌灵、啶虫脒和苯醚甲环唑,进行农药残留慢性膳食摄入风险（%ADI）评估、急性膳食摄入风险（%ARfD）评估,并进行不同消费人群暴露点评估。结果显示：检出的5种农药%ADI均低于100.00%,为0.00023%~0.0059%;%ARfD远低于100%,为0.50%~28.3%,5种农药的急性和慢性摄入风险均为儿童高于成年人,绝大多数女性的摄入风险高于男性;5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咪鲜胺>啶虫脒>苯醚甲环唑>多菌灵>吡虫啉,但点评估结果均远低于100%,说明通过食用番木瓜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。     

欧盟、美国和日本加工农产品中农药残留评估现状

本文介绍了欧盟、美国和日本评估加工农产品中农药残留的数据要求和试验准则,以及开展膳食摄入风险评估和推荐农药最大残留限量(MRL)的方法,汇总了用于农药残留评估的加工农产品及其分类,分析了加工农产品中农药MRL制定现状,为进一步提高我国相关领域技术提供借鉴。比较分析结果表明,欧盟和美国在农药登记资料要求中明确提出了加工试验数据要求并且制定了相应的试验准则,美国在试验准则中描述了加工农产品中农药MRL的推荐原则;美国和日本制定了一定数量的加工农产品中农药MRL,欧盟建立了适用于监管农药MRL的加工因子数据库;欧盟、美国和日本均在相关法规中规定了加工农产品中农药残留的合规性判定。     

超高效液相色谱-串联质谱法测定柑橘中的草甘膦及其代谢物残留

本研究首次建立了一种超高效液相色谱-串联质谱法(UHPLC-MS/MS)同时测定柑橘中草甘膦及其代谢物N-乙酰草甘膦?氨甲基磷酸(AMPA)和N-乙酰AMPA?样品经过0.5%甲酸水提取, 以十八烷基硅烷键合硅胶柱(C18)净化, 利用水和200 mmol/L碳酸氢铵溶液(含0.1%氨水)作为流动相梯度洗脱, 在多反应监测模式下定量分析?结果表明, 草甘膦及其代谢物在0.05~1 mg/kg范围内线性关系良好, 相关系数均大于0.99; 草甘膦及其3个代谢物在柑橘全果和果肉基质中3个加标水平下回收率为 70.5%~109.5%, 相对标准偏差(RSD)为0.6%~10.1%, 定量限为0.05 mg/kg?本方法的前处理样品无需衍生, 简便?快捷?高效?准确可靠, 可用于柑橘中草甘膦及其代谢物N-乙酰草甘膦?AMPA和N-乙酰AMPA的定量检测?     

Challenges and opportunities of unmanned aerial vehicles as a new tool for crop pest control

The application of pesticides is not simply delivering chemicals to the target area. It also involves considering the negative aspects and developing strategies to deal with them during the application process, to ensure the maximization of pesticides use efficiency and the maintenance of the ecosystem. Unmanned aerial vehicle (UAV) sprayers demonstrate unique advantages compared to traditional ground sprayers, particularly in terms of maneuverability and labor intensity reduction, showed great potential for chemical application in pest control. It is undeniable that there exist challenges in the practice of UAV spraying, such as higher potential risks of pesticide drift or pathogen transmission, uncertainty canopy deposition for different crops, and unexpected leaf breakage induced by downwash flow. Maximizing the utilization of downwash flow while avoiding lateral air movement outside the intended target crop area is a major issue for chemical application with UAV sprayers, particularly in light of the increasingly apparent consensus on the need for enhanced environmental protection during the chemical application process. It must be considered that the operation strategy in different scenarios and for different crop targets is not the same, unique requirements should be given on nozzle atomization, flight parameters, adjuvants and aircraft types in specific working situations. In future, the implementation of spray drift prediction, technical procedures development, and other solutions aimed at reducing pesticide drift and improving deposition quality, is expected to promote the adoption of UAV sprayers by more farmers. © 2023 Society of Chemical Industry.     

Ace and ace-like genes of invasive redlegged earth mite: copy number variation,target-site mutations,and their associations with organophosphate insensitivity

Background

Invasive Australian populations of redlegged earth mite, Halotydeus destructor (Tucker), are evolving increasing organophosphate resistance. In addition to the canonical ace gene, the target gene of organophosphates, the H. destructor genome contains many radiated ace-like genes that vary in copy number and amino acid sequence. In this work, we characterise copy number and target-site mutation variation at the canonical ace and ace-like genes and test for potential associations with organophosphate insensitivity. This was achieved through comparisons of whole-genome pool-seq data from alive and dead mites following organophosphate exposure.

Results

A combination of increased copy number and target-site mutations at the canonical ace was associated with organophosphate insensitivity in H. destructor. Resistant populations were segregating for G119S, A201S, F331Y at the canonical ace. A subset of populations also had copy numbers of canonical ace > 2, which potentially helps overexpress proteins carrying these target-site mutations. Haplotypes possessing different copy numbers and target-site mutations of the canonical ace gene may be under selection across H. destructor populations. We also detected some evidence that increases in copy number of radiated ace-like genes are associated with organophosphate insensitivity, which might suggest potential roles in sequestration or breakdown of organophosphates.

Conclusion

Different combinations of target-site mutations and (or) copy number variation in the canonical ace and ace-like genes may provide non-convergent ways for H. destructor to respond to organophosphate selection. However, these changes may only play a partial role in organophosphate insensitivity, which appears to have a polygenic architecture. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.