新型植物源杀虫剂--血根碱对苹果二斑叶螨控制效果初探

2001—2002年，在湖北广水进行的2年1％血根碱可湿性粉剂防治苹果二斑叶螨的田间药效试验表明，1％血根碱可湿性粉剂对苹果二斑叶螨有良好的灭杀效果，使用浓度在2500倍时，防治效果与生产上推广使用的20％哒螨灵可湿性粉剂2500倍液相当。     

高效液相色谱法测定柑桔中噻菌灵残留量的研究

以乙酸乙酯为溶剂，超声波振荡法提取柑桔中的噻菌灵，采用反相高效液相色谱法测定，流动相为甲醇 水 氨水，体积比为70：30：0．6。用外标(峰高)——标准曲线法定量，回收率为80％—89．94％；检测限为0．1mg/kg，符合残留量测定的要求。     

两种复配剂对美洲斑潜蝇的防治效果

摘要以50%灭·丹WP1000～2000倍液,1.8%阿·高氯EC1000倍液防治美洲斑潜蝇,其杀虫效果90%左右,保苗效果80%左右,持效期10天以上。试验浓度范围内对黄瓜苗安全。     

亚热带果树病虫害动态咨询网站的构建及其功能

网站由病虫识别、网络咨询、植物医院、专家论坛、信息快车、BBS等子系统组成。在Frontpage 2000和Dreamweaver 4.0网页编辑工具下开发,采用ASP动态网页技术提高咨询性能,可提供在线病虫识别、发生规律、防治措施、农药品种和防治处方咨询。系统动态性强,果树病虫害最新信息可在网上发布,为同行间的协作提供畅通的交流渠道。网站采用后台管理模式,进行数据添加、修改和维护。     

超临界萃取技术在农药残留分析中的应用研究进展

从超临界流体萃取的原理和特点、提取剂种类、样品前处理、萃取条件的选择、超临界萃取与3种经典提取方法的比较等5个方面进行了综述,并展望了其应用前景,旨在使国内对这项技术在农药残留上的应用引起重视。     

生物组织中多种农药成分的GC/MS分析

本文介绍了对多种农药中毒死亡者体内样品进行检验的方法。组织样品经过液-液萃取及GC／MS检测,从胃组织样品中检出了敌敌畏、克百威、毒鼠强、甲基对硫磷、敌百虫、氯氰菊酯、甲胺磷、马拉硫磷等8种农药残留,并检出甲基对硫磷的代谢产物甲基对氧磷;肝组织、血液样品均检出敌敌畏、克百威、毒鼠强、甲基对硫磷、敌百虫、甲胺磷等6种成分。本文在生物样品中同时检出多种不同极性的残留农药．为在刑事技术领域内毒物的检测、代谢和分布提供了一定的经验及实验数据。     

农药精确对靶施用及其系统设计

提出了减小农药环境污染、增强生态系统可持续性和保护操作者身心健康的精确农药施用系统。系统包括目标树木图像采集处理系统和喷雾控制系统等。树木图像采集处理系统包括CCD摄像头、图像采集卡、计算机软件和试验装置。设计的软件包括采集、提取和处理树木视频图像的关键帧,设计了相对色彩因子从背景中分割出绿色目标,通过分割图像测量获取目标的形态和位置特征。喷雾控制系统包括喷雾台架、喷头、电磁阀和继电器等,以实现数据通讯和将喷雾决策结果转换为指令来控制喷雾执行系统。试验结果表明开发的系统能识别树木图像和树冠类型,并能实现精确对靶喷雾至预定树木目标,从而减小非目标农药污染。     

基于电动比例调节阀的变量施药装置

利用电动比例调节阀作为流量调节执行器,以PLC为控制器,设计了基于流量直接控制方式的变量施药装置,并开发了相应的测控软件。通过试验得出了施药流量与电动比例调节阀开口度的关系,设计出适用于本装置的流量控制算法。试验显示,流量控制时最大平均误差为0.35L/min,最小平均误差为0.01L/min,表明装置能满足变量施药的要求。     

Mineralization of [14C] glyphosate and its plant-associated residues in arable soils originating from different farming systems

The biomineralization of [¹⁴C]glyphosate, both in the free state and as ¹⁴C-residues associated with soybean cell-wall material, was studied in soil samples from four different agricultural farming systems. After 26 days, [¹⁴C]carbon dioxide production from free glyphosate accounted for 34–51% of the applied radiocarbon, and 45–55% was recovered from plant-associated residues. For three soils, the cumulative [¹⁴C]carbon dioxide production from free glyphosate was positively correlated with soil microbial biomass, determined by substrate-induced heat output measurement and by total adenylate content. The fourth soil, originating from a former hop plantation, and containing high concentrations of copper from long-term fungicide applications, did not fit this correlation but showed a significantly higher [¹⁴C]carbon dioxide production per unit of microbial biomass. Although the cumulative [¹⁴C]carbon dioxide production from plant-associated ¹⁴C-residues after 26 days was as high as from the free compound, it was not correlated with the soil microbial biomass. This indicates that the biodegradation of plant-associated herbicide residues, in contrast to that of the free compound, involves different degradation processes. These encompass either additional steps to degrade the plant matrix, presumably performed by different soil organisms, or fewer degradation steps since the plant-associated herbicide residues are likely to consist mainly of easily degradable metabolites. Moreover, the bioavailability of plant-associated pesticide residues seems to be dominated by the type and strength of their fixation in the plant matrix. ©1997 SCI     

Towards the construction of a resistance risk evaluation scheme

Pesticide resistance management needs an indication of the risk of resistance developing in pests against pesticide applications. This paper describes an evaluation system for the ranking of these risks. The term pests includes all organisms which are causing economic damage in agriculture, including weeds and plant pathogens. The system distinguishes six broad risk categories. It is based on expert judgement of answers to a maximum of ten questions on crop husbandry, pest biology and pest control. The system has been developed for registration purposes in The Netherlands, and is currently being discussed within the European and Mediterranean Plant Protection Organisation (EPPO). ©1997 SCI