25%噻嗪酮可湿性粉剂防治核桃桑盾蚧试验

应用25％噻嗪酮可湿性粉剂在核桃桑盾蚧越冬代成虫期和第一代若虫期进行了林间防治试验,结果表明：25％噻嗪酮可湿性粉剂对桑盾蚧成虫没有杀灭作用,但对下一代若虫有一定的控制作用,100,200,400倍液喷雾防治控制效果分别为86.17％,74.57和64.25％,在生产中应用以100倍液效果最好;在若虫期施药对若虫的杀灭效果非常明显,500,1 000,1 500,2 000倍液防治效果分别为95.65％,95.4％,84.34％和65.94％,其中500,1 000倍液防治效果达到了95％以上,在生产上推广使用以1 000倍液浓度为宜.     

混剂中噻嗪酮和毒死蜱的气相色谱分析方法研究

以5%OV-101为色谱柱固定相,邻苯二甲酸双环己酯为内标物,利用GC-FID对噻嗪酮.毒死蜱混配制剂中2种组分进行测定。结果表明,噻嗪酮.毒死蜱混配制剂中2种组分及杂质得到了有效分离,毒死蜱和噻嗪酮的变异系数分别为0.74%和0.93%;回收率分别为99.52%～101.28%、99.23%～101.42%;线性相关系数分别为0.999 7和0.999 5。表明该方法测定噻嗪酮.毒死蜱混配制剂中2种有效成分的质量分数时分离效果好、准确度、精密度高、线性关系好、符合定量分析要求,是一种可行、实用的分析方法。     

超高效液相色谱-串联质谱法分析氟虫双酰胺和噻嗪酮在茭白中的残留及消解动态

建立了超高效液相色谱-串联质谱 (UPLC-MS/MS) 检测氟虫双酰胺和噻嗪酮在茭白中残留的方法。样品采用乙腈提取,乙二胺-N-丙基硅烷 (PSA) 净化,0.1%甲酸-甲醇梯度洗脱,电喷雾正离子扫描,多反应监测模式,超高效液相色谱-串联质谱测定,外标法定量。结果表明:在0.005~1 mg/kg添加水平下,氟虫双酰胺和噻嗪酮在茭白植株和茭白中的平均回收率在81%~107%之间,相对标准偏差在4.2%~11%之间。消解动态规律符合一级动力学方程,氟虫双酰胺和噻嗪酮的半衰期分别为2.3 d和2.8 d,属易降解农药。最终残留试验结果表明:10% 阿维·氟酰胺悬浮剂按制剂用量450~675 g/hm2分别施药2和3次,间隔期5 d,距最后一次施药后7、14和21 d采样,氟虫双酰胺在茭白中的残留量均<0.01 mg/kg;25% 噻嗪酮可湿性粉剂按制剂用量600~900 g/hm2分别施药2和3次,间隔期5 d,距最后一次施药后7、14和21 d采样,噻嗪酮在茭白中的残留量为<0.005~0.078 mg/kg。建议10%阿维·氟酰胺悬浮剂最高制剂用量为450 g/hm2,最多施药2次,安全间隔期以7 d为宜;25%噻嗪酮可湿性粉剂最高制剂用量为675 g /hm2,最多施药2次,安全间隔期以21 d为宜。     

Degradation kinetics and safety evaluation of buprofezin residues in grape (Vitis vinifera L.) and three different soils of India

BACKGROUND: This work was undertaken to determine the preharvest interval (PHI) of buprofezin to minimize its residues in grapes and thereby ensure consumer safety and avoid possible non‐compliance in terms of residue violations in export markets. Furthermore, the residue dynamics in three grapevine soils of India was explored to assess its environmental safety. RESULTS: Residues dissipated following non‐linear two‐compartment first + first‐order kinetics. In grapes, the PHI was 31 days at both treatments (312.5 and 625 g a.i. ha^?1), with the residues below the maximum permissible intake even 1 h after foliar spraying. Random sampling of 5 kg comprising small bunchlets (8–10 berries) collected from a 1 ha area gave satisfactory homogeneity and representation of the population. A survey on the samples harvested after the PHI from supervised vineyards that received treatment at the recommended dose showed residues below the maximum residue limit (MRL) of 0.02 mg kg^?1 applicable for the European Union. In soil, the degradation rate was fastest in clay soil, followed by sandy loam and silty clay, with a half‐life within 16 days in all the soils. CONCLUSION: The recommendation of the PHI proved to be effective in minimizing buprofezin residues in grapes. Thus, this work is of high practical significance to the domestic and export grape industry of India to ensure safety compliance in respect of buprofezin residues, keeping in view the requirements of international trade. Copyright © 2008 Society of Chemical Industry     

Evaluation of alternative rice planthopper control by the combined action of oil-formulated Metarhizium anisopliae and low-rate buprofezin

BACKGROUND: High resistance of brown planthopper (BPH) Nilaparvata lugens Stål to common insecticides is a challenge for control of the pest. An alternative control strategy based on the combined application of fungal and chemical agents has been evaluated. RESULTS: Three gradient spore concentrations of oil‐formulated Metarhizium anisopliae (Metschnikoff) Sorokin (Ma456) were sprayed onto third‐instar nymphs in five bioassays comprising the low buprofezin rates of 0, 10, 20, 30 and 40 µg mL^?1 respectively. Fungal LC₅₀ after 1 week at 25 °C and 14:10 h light:dark photoperiod decreased from 386 conidia mm^?2 in the buprofezin‐free bioassay to 40 at the highest chemical rate. Buprofezin (LC₅₀: 1647, 486 and 233 µg mL^?1 on days 2 to 4) had no significant effect on the fungal outgrowths of mycosis‐killed cadavers at the low application rates. The fungal infection was found to cause 81% reduction in reproductive potential of BPH adults. In two 40 day field trials, significant planthopper (mainly BPH) control (54–60%) was achieved by biweekly sprays of two fungal candidates (Ma456 and Ma576) at 1.5 × 10¹³ conidia ha^?1 and elevated to 80–83% by incorporating 30.8 g buprofezin ha^?1 into the fungal sprays. CONCLUSION: The combined application of the fungal and chemical agents is a promising alternative strategy for BPH control. Copyright © 2010 Society of Chemical Industry     

低浓度噻嗪酮与黄绿绿僵菌对褐飞虱协同作用的生物测定

在实验室中测定了低浓度噻嗪酮与黄绿绿僵菌 Metarhizium anisopliae var.acridum 对褐飞虱 Nilaparvata lugens 不同龄期若虫和成虫的协同致死作用。结果表明,低浓度噻嗪酮与黄绿绿僵菌混合施用时对褐飞虱表现明显的协同作用。与单独施用噻嗪酮相比,混合施用时对低龄若虫的 LT_(50)缩短了约22天;对高龄若虫的 LT_(50)缩短了约57天;单独施用时对成虫几乎没有作用,而混合施用时的 LT_(50)为3.77天。与单独施用黄绿绿僵菌相比,混合施用时对低龄若虫、高龄若虫、成虫的 LT_(50)也都缩短了1～2天。混合施用时对不同发育阶段的褐飞虱的毒力顺序为成虫>高龄若虫>低龄若虫。     

气相色谱法对毒死蜱、啶虫脒和噻嗪酮的定量分析

采用气相色谱法用SUBTM-5型毛细管柱,以双甲脒为内标物,NPD检测器对毒死蜱、啶虫脒和噻嗪酮3种农药制剂进行了同时定量分析。结果表明,毒死蜱的线性回归方程为y=1．570486x＋0．54676（r=0.9982）,有效成分含量为32．58％;啶虫脒的线性回归方程为y=0．544916x＋0.859651（r=0.9989）,有效成分含量为45.62％;噻嗪酮的线性回归方程为y=0．743658x＋1．243762（r=0．9997）,有效成分含量为27．83％。     

噻嗪·异丙威25%可湿性粉剂的气相色谱分析

本文介绍了以5%OV-101色谱柱固定相,邻苯二甲酸二丁酯为内标物,用FID检测器利用程序升温对噻嗪·异丙威25%可湿性粉剂2种组分的气相色谱分离测定方法。结果表明,噻嗪酮和异丙威的标准偏差分别为0.026、0.047,变异系数分别为0.32%、0.28%,噻嗪酮的回收率为99.34%～101.03%,异丙威的回收率为99.16%～101.47%。该方法简便、快捷、准确。     

褐飞虱对吡虫啉、噻嗪酮和氟虫腈的抗性监测

2005年10月至2007年10月,用稻茎浸渍法测定12个褐飞虱种群对吡虫啉、噻嗪酮和氟虫腈的敏感性。结果表明：12个褐飞虱种群对吡虫啉均达高或极高水平抗性;除2005年南宁、韶关和阳江,2006年阳江及2007年永州5个褐飞虱种群对噻嗪酮仍处于敏感水平外,其余种群处于敏感性降低或达到低水平抗性;而2006年阳江褐飞虱种群对氟虫腈处于敏感性降低阶段,其余的8个种群均达到了低或中等水平抗性。