Susceptibility of female populations of <Emphasis Type="Italic">Panonychus ulmi</Emphasis> (Koch) (Acari: Tetranychidae) to some acaricides in apple orchards

The levels of susceptibility of adult female European red mite, Panonychus ulmi (Koch) populations collected from apple orchards in Bursa region of Turkey, to acaricides, dicofol, bromopropylate and fenpyroximate belong to two different groups and an acaricide–insecticide, amitraz, were determined by a petri leaf disk-Potter spray tower method. When compared with the susceptible population, resistance ratios, as indicated by LC₅₀ values, ranged from 2.2 to 11.9, 0.8 to 3.6, 1.0 to 22.5 and 0.9 to 7.9, while LC₉₀ values varied from 1.6 to 9.8, 1.0 to 5.4, 1.0 to 47.4, 1.4 to 36.6, respectively, for amitraz, dicofol, bromopropylate and fenpyroximate. An examination of bioassay responses showed that susceptibility was lower for fenpyroximate and bromopropylate than for the other two compounds in the order of amitraz < dicofol. In conclusion, P. ulmi susceptibility to tested compounds varied widely from location to location.     

气相色谱/串联质谱法测定芒果中的腈苯唑和溴螨酯残留

建立了气相色谱/三重串联四级杆质谱分析芒果中腈苯唑和溴螨酯农药残留的方法。采用乙腈提取,Carbon/NH2固相萃取小柱净化后采用气相色谱/三重串联四级杆质谱多反应(MRM)模式下进行外标法定量测定,并对腈苯唑和溴螨酯的基质效应进行分析。结果表明:2种农药在0.01~1.00 mg/L范围内线性关系均良好。该方法对腈苯唑和溴螨酯的检出限(LOD)分别为0.003、0.002 mg/kg,定量限(LOQ)分别为0.010、0.008 mg/kg。在0.01~0.05 mg/kg浓度添加水平下,2种农药的平均回收率处于76.5%~89.6%之间,相对标准偏差(RSD)不大于10.3%。该方法背景干扰少,灵敏度高,重复稳定性好,可用于分析芒果中腈苯唑和溴螨酯的残留测定。     

白菜和黄瓜中溴螨酯的残留方法研究

建立了白菜和黄瓜中溴螨酯残留的测定方法。样品经乙腈提取,弗罗里硅土固相萃取小柱净化,采用气相色谱-电子捕获检测器测定。实验证明,白菜和黄瓜中溴螨酯的平均添加回收率在87．6％～99．5％之间,变异系数在3．5％～8．7％之间,最低检出浓度为0．005mg／kg。     

气相色谱法同时检测蜂蜜中溴螨酯、蝇毒磷、氟胺氰菊酯和氟氯苯氰菊酯残留

本文建立了同时测定蜂蜜中溴螨酯、蝇毒磷、氟胺氰菊酯和氟氯苯氰菊酯等四种农药残留的分析方法.蜂蜜样品用水溶解后经正己烷-二氯甲烷提取,Oasis HLB固相萃取柱萃取净化,正己烷-二氯甲烷洗脱吹干后,用内标溶液定容,采用气相色谱电子捕获检测器进行测定.在0.004mg/kg～0.160mg/kg添加水平,四种农药的回收率在70%～110%之间,各农药的检出限在0.004mg/kg～0.008mg/kg之间.