溴氰菊酯泡腾片浸泡蚊帐对淡色库蚊和致倦库蚊的灭效观察

目的在实验室内观察溴氰菊酯泡腾片及乳油浸泡蚊帐对淡色库蚊和致倦库蚊的灭效。方法强迫接触法。结果当药剂浓度为2mg·ai／m2时，溴氰菊酯2种剂型浸帐对淡色库蚊的杀灭效果均达到100％，当药剂浓度达到10mg·ai／m2时，其对致倦库蚊杀灭效果不足100％。溴氰菊酯泡腾片浸泡蚊帐杀灭淡色库蚊的LC50为0．23mg·ai／ml，而乳油浸帐的LC50为0．31mg·ai/ml，方差分析结果表明，二者差异有统计学意义（t=3．04，P=0．023）；溴氰菊酯2种剂型浸帐对致倦库蚊的LC50分别为1．16和1．33mg·ai／ml，差异无统计学意义（t=1．65，P=0．470）。溴氰菊酯的2种剂型均采用5、10和20mg·ai／nl2 3种浓度浸泡蚊帐，对淡色库蚊和致倦库蚊的毒杀效果随着药物浓度的增高，LT50值明显缩短；溴氰菊酯泡腾片浸泡蚊帐对2种蚊虫的灭效均稍强于乳油浸泡蚊帐，且泡腾片浸泡蚊帐对2种蚊虫的击倒死亡时问均短于乳油浸帐。结论溴氰菊酯泡腾片作为一种新剂型浸泡蚊帐具有良好的灭蚊效果。     

烯虫酯对家蝇幼虫的毒性及滞育作用研究

目的观察研究烯虫酯对家蝇幼虫的毒性及滞育作用。方法采用饲料混药喂食法,针对不同质量浓度的烯虫酯对家蝇幼虫的致死作用及幼虫化蛹发育历期的影响,设置不同的处理组和重复。结果烯虫酯对家蝇幼虫的LC50为2.140 3×10-5 mg/kg;随着药剂质量浓度的提高,幼虫死亡率呈明显升高趋势。不同质量浓度的烯虫酯使家蝇幼虫化蛹的发育历期明显延长。结论烯虫酯对家蝇幼虫有明显的毒杀作用,并阻碍幼虫的发育及变态过程,从而影响成虫存活。     

5株虫生真菌对淡色库蚊幼虫的致病力研究

目的测定菌株对淡色库蚊幼虫的致病力,筛选出高致病力菌株,为淡色库蚊的防治提供理论依据。方法选择生物防治中常用的5株菌株,测定不同浓度的孢子悬浮液对淡色库蚊幼虫的累计死亡率,计算半数致死浓度（LC50）。结果菌株GIM3.428、GIM3.45、GIM3.431、GIM3.95以及GIM3.436对淡色库蚊幼虫均具有致病性,试验10d,淡色库蚊幼虫累计死亡率分别为100%、82%、79%、73%和57%,菌株对淡色库蚊幼虫的LC50分别为2.98×102、1.41×103、1.26×104、1.02×104、2.07×105孢子/ml。结论菌株GIM3.428对淡色库蚊幼虫的致病力最高,可将其应用于淡色库蚊的防治。     

S-烯虫酯抑制捕蝇笼诱饵蝇类羽化的研究

目的观察S-烯虫酯可湿性粉剂抑制捕蝇笼诱饵蝇类羽化的现场效果。方法捕蝇笼诱捕法。结果S-烯虫酯可湿性粉剂10、50、100 mg/kg 3个浓度组的羽化抑制率分别为17.97%、74.42%和91.76%,3个浓度组效果差别显著(χ2=302.653,P0.05),100 mg/kg浓度组效果最好。蝇类死于前蛹期、蛹期和羽化期,以蛹期为主,占68.28%。结论用100 mg/kg S-烯虫酯可湿性粉剂控制捕蝇笼诱饵的蝇类羽化效果明显,S-烯虫酯能够抑制蝇类羽化。     

实验用淡色库蚊、白纹伊蚊适宜取虫时间段的研究

目的明确实验用淡色库蚊、白纹伊蚊不同性别羽化时间段,确定实验用虫最佳取蚊时间,以提高工作效率,保证药效实验的快速顺利完成。方法对2种试虫进行标准化饲养,研究不同羽化时间段雌雄蚊的数量及比例。结果淡色库蚊和白纹伊蚊蛹开始羽化后,均在第2、3天达到高峰,且羽化成蚊主要在前4天内完成;在整个羽化过程中,前2天羽化成蚊以雄蚊占绝大多数,之后雌蚊比例逐渐增加;羽化结束,雌雄性比接近1:1。结论在驱、灭蚊制剂药效登记实验中,取第3～4天羽化的蚊虫作为实验用蚊备选群体,雌虫比例高,可方便、快捷地满足实验需求。     

植物粗提物对淡色库蚊幼虫的生物活性

目的筛选对淡色库蚊有生物活性的植物资源,为植物源农药的开发研制提供理论依据。方法分别利用水、乙醇和丙酮3种溶剂提取植物的有效成分,测定不同溶剂植物粗提物对淡色库蚊幼虫的生物活性,挑选12种效果好的植物,进一步研究其乙醇提取物对淡色库蚊幼虫的毒杀效果。结果 55种供试植物中有43种植物对淡色库蚊幼虫有生物活性,12种植物的乙醇提取物24 h对淡色库蚊幼虫的LC50〈3 mg/ml,其中7种植物的LC50〈1mg/ml。结论自然界中对淡色库蚊有生物活性的植物种类多,为植物源农药的开发研制提供了资源。     

S-烯虫酯控制城市雨水井蚊幼虫羽化的效果观察

目的观察S-烯虫酯缓释块抑制城市雨水井蚊幼虫羽化的现场防治效果。方法 S-烯虫酯在居民住宅雨水井中每月投放1次抑制蚊幼虫羽化,投放剂量为1 mg/L。评价方法是采集现场雨水井中的Ⅲ龄幼虫(蛹)带回实验室观察羽化情况。结果投药后10 d与30 d的蚊虫羽化抑制率分别为86.44%和86.42%,两者与对照组相比均有显著性差别(分别为χ~2=568.935 6,P=0.000 0和χ~2=354.751 1,P=0.000 0)。结论S-烯虫酯缓释块能够有效地控制城市雨水井中的蚊幼虫羽化为成虫,持效期较长。     

吡丙醚5%水乳剂和0.5%颗粒剂对淡色库蚊幼虫及蛹杀灭效果的观察

目的观察有效成分为吡丙醚的5%水乳剂和0. 5%颗粒剂对淡色库蚊幼虫和蛹的杀灭效果,为蚊虫防治提供依据。方法选取Ⅲ龄期的淡色库蚊幼虫放入装有脱氯自来水的白瓷盆内,按推荐使用剂量施药于盆内,每天观察并记录施药后幼虫及蛹的死亡数和正常羽化虫数。结果 1 g/m 25%吡丙醚水乳剂和10g/m 20. 5%吡丙醚颗粒剂对幼虫和蛹都有良好的杀灭效果,幼虫总死亡率分别为35. 0%和27. 3%,蛹死亡率均为100%,正常羽化为0。结论吡丙醚对淡色库蚊幼虫和蛹具有良好的杀灭效果,可用于蚊虫孳生地防治蚊虫,水乳剂对幼虫杀灭率略高于颗粒剂。     

2018年许昌市淡色库蚊对5种常用杀虫剂抗药性调查

目的了解河南省许昌市淡色库蚊对5种常用杀虫剂的抗药性水平,为科学合理选择和使用杀虫剂,防控蚊媒传染病提供理论依据。方法现场采集淡色库蚊卵块,实验室饲养繁殖至三龄末四龄初,采用幼虫浸渍法测定淡色库蚊抗药性。结果2018年淡色库蚊对氯菊酯的抗性为抵抗,半数致死浓度(LC50)为0.0827 mg/L,抗性倍数为3.23倍;对溴氰菊酯抗性为高抗,LC50为0.0121 mg/L,抗性倍数为60.50倍;对高效氯氰菊酯抗性为抵抗,LC50为0.0150 mg/L,抗性倍数为3.85倍;对仲丁威抗性为敏感,LC50为0.6841 mg/L,抗性倍数为1.16倍;对双硫磷抗性为敏感,LC50为0.0011 mg/L,抗性倍数为2.20倍。结论淡色库蚊对拟除虫菊酯类杀虫剂产生了不同程度的抗药性,对有机磷类和氨基甲酸酯类杀虫剂尚未产生抗药性。应继续加强对淡色库蚊的抗药性调查工作,坚持采用综合防制的办法,科学合理使用杀虫剂,以延缓蚊虫抗药性的发生和发展。     

淡色库蚊和致倦库蚊对杀虫剂抗药性的调查研究

目的 了解我国不同地区淡色库蚊和致倦库蚊对常用拟除虫菊酯类杀虫剂的抗性水平,为合理有效地使用化学杀虫剂提供依据.方法 采用滤纸接触筒法测定成蚊对10 000 mg/L溴氰菊酯和10 000 mg/L氯菊酯的1h击倒率和24 h死亡率.结果 北京市、河北和海南省淡色库蚊及致倦库蚊在溴氰菊酯和氯菊酯区分剂量下的24 h死亡率均＜80％,均为抗性种群.7株淡色库蚊对10 000 mg/L氯菊酯的24 h死亡率均＜50％;13株蚊虫对10 000 mg/L溴氰菊酯的抗性高低不一,24 h死亡率1％～66％不等.结论 北京市、河北及海南省淡色库蚊和致倦库蚊对拟除虫菊酯类杀虫剂均产生了高抗性,蚊虫抗药性的产生与杀虫剂的使用密切相关,在创建文明卫生城市工作中要科学合理用药,开展抗药性监测,采取适当措施延缓蚊虫抗药性的产生和发展.     

洗涤灵杀灭白纹伊蚊蛹的效果观察

目的研究日用洗涤灵对白纹伊蚊蛹杀灭效果。方法试验设洗涤灵0．05、0．1、0．2、0．5、1．0mL／L5个浓度组和一个脱氯自来水对照组。每个浓度加试验液200ml．放30只蛹。观察试验当天（T＋0d）、24h（T＋1d）、48h（T＋2d）、72h（T＋3d）蛹死亡数、活蛹数、成功羽化数和羽化后成蚊淹死数。每组均做2次平行试验。比较不同浓度组蛹死亡率、蛹平均死亡时间、羽化率、平均羽化时间、成蚊淹死率差异,用Bliss法计算洗涤灵致蛹死亡的LD50.结果洗涤灵高浓度组蛹死亡率明显高于低浓度组和对照组（x^2=252．8,P=0）;洗涤灵致蛹死亡的LD50为0．1ml／L。洗涤灵高浓度组蛹平均死亡时间低于低浓度组和对照组（x^2=92．3,P=0）;洗涤灵高浓度组羽化率明显低于低浓度组和对照组（x^2=255．4,P=0）;不同浓度的洗涤灵对蛹的平均羽化时间没有影响（x^2=0．478,P=0．784）;洗涤灵浓度达到0．1ml／L时,成蚊淹死率已达100％。0．05ml／L浓度组成蚊淹死率明显高于对照组（x^2=49．3,P=0）。结论洗涤灵较低浓度能对白纹伊蚊蛹起到很好的防治效果,其机理可能与洗涤灵降低水的表面张力后干扰蛹呼吸和阻止羽化后成蚊飞离水面有关．     

高效液相色谱法同时测定多种食品添加剂方法研究

[目的]建立高效液相色谱法同时测定食品中安赛蜜、苯甲酸、山梨酸、糖精钠。[方法]水超声提取样品,必要时用亚铁氰化钾溶液（106g／L）和乙酸锌溶液（220g／L）净化;样液采用Kromasil C18柱（150mm×4．6mm,5μm）色谱柱,流动相为甲醇-0．02mol／L乙酸铵溶液（6：94,V／V）,二极管阵列检测器进行检测;以保留时间和紫外吸收光谱图结合定性,外标法测定食品种4种食品添加剂含量。[结果]4种食品添加剂的检出限分别为安赛蜜9．00×10^-5mg／ml、苯甲酸1．20×10^-4mg／ml、山梨酸1．00×10^-4mg／ml、糖精钠1．60×10^-4mg／ml;各组分回收率在89．0％～100．0％之间;各组分测定RSD均小于5％。[结论]该法特异性强、灵敏度高,操作简便快速,测定结果可靠,适用于食品中上述4种添加剂的常规分析。     

Survival, mobility, and membrane-bound enzyme activities of freshwater planarian, Dugesia japonica, exposed to synthetic and natural surfactants

Surfactants are a major class of emerging pollutants widely used in large quantities in everyday life and commonly found in surface waters worldwide. Freshwater planarian was selected to examine the effects of different surfactants by measuring mortality, mobility, and membrane-bound enzyme activities. Among the 10 surfactants tested, the acute toxicities of betaine and polyethylene glycol (PEG-200) to planarians were relatively low, with a median lethal concentration (LC50) greater than 10,000 mg/L. The toxicity to planarians of the other eight surfactants based on 48-h LC50 could be arranged in the descending order of cetylpyridinum chloride (CPC)?>?4-tert-octylphenol (4-tert-OP)?>?ammonium lauryl sulfate?>?benzalkonium chloride?>?saponin?>?sodium lauroylsarcosinate?>?dioctyl sulfosuccinate?>?dodecyl trimethyl ammonium bromide (DTAB). Both CPC and 4-tert-OP were very toxic to planarians, with 48-h LC50 values <1 mg/L. The median effective concentrations (EC50s) of planarian mobility were in the 0.1 to 50 mg/L range and were in the same range as the 24-h LC50 of planarians exposed to different surfactants, except for DTAB. In addition, significant inhibition of cholinesterase activity activities was found in planarians exposed to 4-tert-OP at 2.5 and 5 mg/L and to saponin at 10 mg/L after 2-h treatments. This result suggests that planarian mobility responses can be used as an alternative indicator for acute toxicity of surfactants after a very short exposure period.     

多重耐药质粒RP4在膜生物反应器中的水平转移

目的研究多重耐药质粒RP4在膜生物反应器(MBR)中水平转移情况,进而预测MBR处理含有耐药基因污水的生态风险。方法向正常运行的MBR中接种E.coli K12(RP4)Rif,利用含有不同抗生素的营养琼脂培养基选择性平板计数,得出可培养接合子数量和接合转移率;并利用实时定量PCR方法检测污泥中耐药质粒RP4;同时监测MBR对NH4+-N、CODCr的去除效率和污泥浓度(MLSS),以评价MBR运行效能。结果接种供体菌后,可培养接合子数量、转移频率由0逐渐升高,接种供体菌后第9 d,接合子数量增加到3.38×104cfu/ml、接合转移率达1.70×10-3/cell;随后,可培养接合子数量、接合转移率都呈现波动下降(于第23天分别下降至2.55×102cfu/ml、3.20×10-5/cell);与实时定量PCR检测结果基本一致。供体菌的引入对MBR去除NH4+-N、CODCr的效率都有一定影响,即先降低后逐渐升高,污泥浓度由2200 mg/L逐渐降低至约1100 mg/L。结论实验过程中,RP4质粒在反应器中发生了较高频率的接合转移,并对反应器NH4+-N、CODCr的去除效率都产生影响。     

龙胆抗病毒有效部位(RG2-1)体外抗呼吸道合胞病毒作用机制的初步研究

目的研究龙胆抗病毒有效部位(RG2-1)体外抗呼吸道合胞病毒(RSV)的作用及其作用机制。方法经水提醇沉得到RG2-1,MTT法检测细胞毒性,以利巴韦林为阳性对照药物,通过细胞病变效应(CPE)观察RG2-1对RSV感染细胞的封闭作用、直接灭活作用、对RSV在细胞内增殖的抑制作用以及预防作用,从而对其抗病毒机制进行初步研究。结果RG2-1的半数中毒浓度(TC50)为11.07mg/ml,药物直接灭活作用、对RSV在细胞内增殖的抑制作用以及预防作用的半数有效浓度(EC50)分别为0.43、0.42和0.48mg/ml,治疗指数(TI)为25.75、26.36和23.06。结论RG2-1在体外能明显抑制RSV引起的CPE效应,CPE抑制率随着药物浓度的增加而增高;RG2-1能通过多种途径发挥抗RSV的作用。     

The short-term toxicity of some feed additives to different freshwater organisms

Summary The short-term toxicity (EC₅₀ respectively LC₅₀ after 2 or 4 days) of 13 feed additives was determined to 4 freshwater organisms of different trophical levels: Chlorella pyrenoidosa, Daphnia magna, Lebistes reticulatus and Salmo gairdneri. The most toxic (LC(EC)₅₀ < 1 mg/1) were robenidine (to all tested organisms) and stenorol (to Daphnia); moderately toxic (1 < LC(EC)₅₀ < 10 mg/1) was pyrimethamine. Amprolium, ethopabate, furazolidone and zoalene proved to be little toxic (LC (EC)₅₀ > 10 mg/1); whereas buquinolate, carbadox, clopidol, decoquinate, grofas and sulfaquinoxaline were under the experimental conditions not toxic for the tested organisms.     

龙胆抗病毒有效部位RG2-1体外抗RSV作用的实验研究

目的了解龙胆抗病毒有效部位RG2-1对呼吸道合胞病毒（RSV）的体外抑制作用。方法经水提取、二氯甲烷萃取、离心后，得到龙胆抗病毒有效部位RG2-1，并以利巴韦林为阳性对照药物，采用细胞病变抑制实验观察其在Hela细胞中对RSV的抑制作用。结果RG2-1的半数中毒浓度（TC50）为10．66mg／ml^-1，抑制RSV的半数有效浓度（EC50）为0．42mg／ml，治疗指数（TI）为25．38；随着药物浓度的增加，CPE抑制率明显增高，且对RSV的抑制作用存在明显的量效反应关系（P〈0．05）。结论RG2-1在Hela细胞中对RSV具有明显的抑制作用。     

Effects of insect growth regulators on the nontarget soil arthropod Folsomia candida (Collembola)

The aim of this study was to assess the effect of several insect growth regulators (IGRs) on the nontarget soil arthropod Folsomia candida (Collembola). The survival and reproduction rates of F. candida were evaluated after 28 days of exposure to six IGRs (methoprene, fenoxycarb, precocene II, tebufenozide, hexaflumuron and teflubenzuron) and to one herbicide (diuron) in artificial soil. The differences in the sensitivity of F. candida to these different substances are high. The chitin synthesis inhibitors teflubenzuron and hexaflumuron were the most toxic compounds with an EC50 of 0.05 mg/kg (dry weight) for teflubenzuron and an EC50 of 0.6mg/kg for hexaflumuron. Teflubenzuron is toxic for F. candida at concentrations that are probably close to environmental levels of this insecticide. Inhibition of reproduction is strongly related to adult survival for the juvenile hormone agonist methoprene and for the antijuvenile hormone precocene II, with an EC50 of 173 mg/kg and a LC50 of 178mg/kg for methoprene and an EC50 of 15 mg/kg and a LC50 of 26 mg/kg for precocene II. Fenoxycarb, another juvenile hormone analog, showed a dose-response curve for mortality different from that of methoprene; at concentrations such as 3052 mg/kg no effect on adult survival was observed. However, the EC50 value of 113mg/kg is of the same order of magnitude as that obtained for methoprene. A test with compressed soil contaminated with fenoxycarb was conducted to observe parameters such as numbers of eggs laid and juveniles hatched. No differences were observed between these two endpoints for fenoxycarb. An EC50 of 109 mg/kg was obtained for the ecdysone agonist tebufenozide. The herbicide diuron showed a relatively high toxicity for F. candida with an EC50 of 20 mg/kg. Our results show that some of the tested IGRs can have effects on Collembola at environmentally relevant concentrations (toxicity/exposure ratios < 5 for teflubenzuron, hexaflumuron, and diuron).     

Use of Japanese Medaka (Oryzias latipes) and Tilapia (Oreochromis mossambicus) in Toxicity Tests on Different Industrial Effluents in Taiwan

In Taiwan, aquatic toxicity tests for industrial effluents are not required for discharge permits. However, relying on traditional chemical and physical characteristics of an effluent to monitor and regulate such discharges to manage water quality of a receiving water is insufficient. In this study, we used two fish species, Japanese medaka (Oryzias latipes) and tilapia (Oreochromis mossambicus), and three toxic endpoints, including acute and subacute toxicity, to determine toxicity of seven different types of industrial effluents. Prior to the study, two reference toxicants were tested on two fish species. The LC50s of CdCl₂ for tilapia and medaka juveniles were 29.6 ± 15.3 mg/L and 2.2 ± 1.2 mg/L, respectively. The sensitivity of medaka embryo mortality and hatching inhibition to CdCl₂ were about the same, with the LC50 and EC50 of 0.3 ± 0.1 mg/L and 0.1 ± 0.1 mg/L, respectively. The LC50s for tilapia and medaka juveniles to sodium dodecyl sulfate (SDS) were 19.7 ± 10.6 mg/L and 12.5 ± 5.9 mg/L. The medaka embryo was less sensitive to SDS than to CdCl₂. The embryo's LC50 for SDS was 5.8 ± 2.8 mg/L and the hatching inhibition EC50 was 1.3 ± 1.1 mg/L. Results of toxicity tests on different effluents showed that the electroplating effluent was the most toxic, followed by acrylonitrile manufacturing and pulp/paper mill discharges. The LC50s of the electroplating effluent to different assays were in the range of several percents of the whole effluent. The pulp/paper effluent was toxic only to the medaka embryo. The rest of the industrial effluents tested showed either moderate or no toxicity to the animals. Received: 12 June 2000/Accepted: 6 September 2000