糙米中丁硫克百威及其代谢物的残留测定

[目的]监测与评价糙米中丁硫克百威及其代谢物克百威、3-羟基克百威的残留量。[方法]建立凝胶渗透色谱（GPC）净化、气相色谱-质谱（GC-MS）同时测定糙米中丁硫克百威及其代谢物克百威、3-羟基克百威残留的方法。样品中的待测农药组分采用环己烷-乙酸乙酯（1∶1,V/V）提取,GPC和中性氧化铝（A l2O3）小柱净化,GC-MS测定。[结果]丁硫克百威和克百威的最低检测量均为2.0×10-11g,3-羟基克百威为1.0×10-10g;最低检出质量分数均为0.1 mg/kg,各组分的添加回收率为77.8%～94.6%,变异系数为3.86%～6.58%。[结论]凝胶渗透色谱净化-气相色谱质谱法测定丁硫克百威及其代谢物在糙米中的残留方法灵敏度、准确度、精密度均符合农药残留分析的要求,可用于检测糙米中丁硫克百威及其代谢物的残留量。     

丁硫克百威在韭菜中的转化情况

[目的]探究丁硫克百威在韭菜中的降解情况。[方法]选取基质效应较重的韭菜做本底,采用配C18色谱柱的液质联用仪测定丁硫克百威在0.050、0.200 mg/kg 2种浓度水平下的添加回收率。[结果]丁硫克百威在测定中可转化为克百威和3-羟基克百威,并且在15 d左右基本降解到国家限量值以下。[结论]改进后的液质联用技术具有精密度高、前处理操作简便、稳定性好等优点,满足农药多残留分析要求。     

丁硫克百威与吡虫啉不同配比对苹果黄蚜的室内毒力测定

室内毒力测定表明 ,丁硫克百威与吡虫啉不同配比的混合物对苹果黄蚜均有一定的增效作用 ,其中 2∶1混配物的增效作用幅度最大。     

Management of the root-knot nematode Meloidogyne graminicola infesting rice in the nursery and crop field by integrating seed priming and soil application treatments of pesticides

The study evaluates the effects of seed priming (5 g or ml kg⁻¹ seed) and soil application (2 kg or l ha⁻¹) of eight organophosphate pesticides on rice root-knot disease caused by Meloidogyne graminicola. Seed priming (SP) or soil application (SA) of phorate, carbofuran and chlorpyriphos (1000 J₂ of M. graminicola kg⁻¹ soil) suppressed galling in the rice nursery by 92 and 99%, 80 and 88% and 76 and 80%, respectively, over control. Relatively similar decreases in the galling were recorded when this nursery was grown for four months in the sterilized soils in earthen pots. Rice cv. PS-5 grown in naturally infested soil in earthen pots (1000 J₂ kg⁻¹ soil) became stunted, showing chlorotic foliage, and terminal galls developed on the roots. The treatment of SP + SA 15 + 30 days after planting (DAP) with phorate, carbosulfan, and chlorpyriphos significantly suppressed the root-knot development and improved the plant growth of rice over the controls (P ≤ 0.05). The overall effect of the SP + SA 15 DAP treatments was marginally weaker than the SP + SA 15 + 30 DAP treatments but statistically on par. Under field conditions, the greatest decrease in the galling occurred due to SP + SA 15 + 30 DAP of phorate (69−71%) and SP + SA 15 DAP (65−67%) followed by carbosulfan and chlorpyriphos. The yield of rice plants was also highest with phorate (32−36% and 29−34%) over the control during the two years of the study. The soil population of M. graminicola decreased by 58–84% over four months due to the phorate treatments. The study demonstrates that seed priming with phorate effectively controls nematode infections in the nursery and that soil application at 15 DAP (2 kg ai ha⁻¹) prevents root-knot development in an infested field under irrigated conditions. Use of SP + SA 15 DAP may enable to avoid one soil application of phorate in the field.     

新农药防治抗性棉蚜试验

１９９３～１９９５年在太原、临猗等地进行了咪蚜胺、硫丹和丁硫克百威防治棉蚜田间药效试验。结果表明，这３种新农药对棉花苗期蚜虫均有良好的防治效果，尤以咪蚜胺和丁硫克百威的防效最为突出。在棉蚜发生盛期，２５％咪蚜胺可湿性粉剂以２０００倍液喷雾防治，２～１４天的防效可达９５％～１００％，持效期在１４大以上；２０％丁硫克百威乳油以１０００～２０００倍液喷雾，１～５天的防效可达９２％～１００％。试验充分说明咪蚜胺的防效和持效，明显好于对照农药４０％久效磷水剂，是理想的防治抗性棉蚜的替代药剂。     

吡虫啉等6种杀虫剂对河北省不同地区绿盲蝽的室内毒力

采用叶片浸渍法,测定了吡虫啉、氟虫腈、高效氯氟氰菊酯、丁硫克百威、马拉硫磷和辛硫磷6种杀虫剂对河北省不同地区绿盲蝽种群的室内毒力效果。结果表明：氟虫腈对河北省绿盲蝽毒力最高,高效氯氟氰菊酯和丁硫克百威次之,马拉硫磷、辛硫磷和吡虫啉毒力较低;河北省不同地区绿盲蝽种群对药剂敏感性的差异较小,其中保定地区绿盲蝽种群对各药剂的敏感性最高。攀     

丁硫克百威原药和制剂对蚯蚓的毒性及其降解产物克百威的动态变化

为了解蚯蚓急性毒性试验过程中丁硫克百威降解产物克百威的动态变化。采用固相萃取高效液相色谱柱后衍生荧光检测法检测土壤中克百威的动态变化，比较不同浓度的90％丁硫克百威原药和20％丁硫克百威乳油制剂在土壤主要代谢产物克百威中的动态变化及其对蚯蚓的毒性。结果表明：当90％丁硫克百威原药的浓度为42.74、85.47、170.94、341.88、512.82 mg/kg时，试验第7天，土壤中克百威的浓度分别为12.941、25.272、56.652、104.984、143.870 mg/kg；而当20％丁硫克百威制剂的浓度为42.74、85.47、170.94、341.88、512.82 mg/kg时，试验第7天，克百威的浓度分别18.445、41.793、67.709、119.515、144.538 mg/kg。第7天时丁硫克百威原药和制剂在土壤中对蚯蚓的LC50分别为170.514、113.757 mg/kg，实际测得的丁硫克百威对土壤中蚯蚓的毒性已演变成丁硫克百威及其降解产物的联合毒性。土壤中克百威的浓度，与添加丁硫克百威的浓度、时间呈正相关，20％丁硫克百威乳油制剂在土壤中的代谢能力及其对土壤中蚯蚓的毒性均高于原药。     

5%丁硫克百威颗粒剂防治稻水象甲幼虫的初步研究

以5%丁硫克百威颗粒剂为供试药剂,设计秧田期和移栽7 d后两个时期撒施,考察其对稻水象甲幼虫的防治效果以及对水稻产量的影响。结果表明:秧田期施药防治能有效降低虫口密度,减轻大田防治压力;与空白对照相比,秧田期防治和移栽7 d后防治的水稻产量分别提高了107.52%和60.26%。