植物性杀虫剂防治玉米象的研究进展

本文系统介绍了各种植物性杀虫剂防治玉米象的研究方法，阐述了目前在玉米象防治中已利用的植物性杀虫剂的研究成果和应用价值。     

Residual toxicities and persistence of organophosphorus insecticides mixed with carbaryl as structural treatments against three liposcelidid psocid species (Psocoptera: Liposcelididae) infesting stored grain

Four organophosphorus insecticides, azamethiphos, fenitrothion, chlorpyrifos-methyl, and pirimiphos-methyl were each mixed with carbaryl and evaluated as structural treatments on concrete and galvanized steel panels (0.3×0.3 m) against adults of three liposcelidid psocids: Liposcelis bostrychophila Badonnel, L. entomophila (Enderlein), and L. paeta Pearman. Residual toxicities and persistence of these insecticide mixtures were assessed at 30±1°C, 70±2% r.h., and a photoperiod of 12:12(L:D) h from 1 day after treatment (0 week) and at weeks 1, 2, 4, 6, and 8, and then every 4 weeks up to week 40. Mortality was recorded at exposure periods of 6 h and then every 24 h until end-point was achieved. Significant enhancement in residual toxicities was observed in azamethiphos plus carbaryl against L. entomophila, and chlorpyrifos-methyl plus carbaryl and pirimiphos-methyl plus carbaryl against all three species on steel surfaces, compared with the individual effectiveness of these insecticides reported earlier. We conclude that combining carbaryl with either azamethiphos, chlorpyrifos-methyl, or pirimiphos-methyl as a structural treatment will provide long-term protection (up to 40 weeks) against infestation by all three psocid species on steel storage structures, whilst carbaryl with fenitrothion will give shorter protection (up to 8 weeks). On concrete structures, however, only azamethiphos plus carbaryl will provide long-term protection against L. bostrychophila (up to 28 weeks) and L. paeta (up to 16 weeks). None of the four insecticide mixtures studied would provide long-term protection against an L. entomophila infestation on concrete surfaces.     

食品中新烟碱类杀虫剂污染与控制研究进展

新烟碱类杀虫剂的问世给世界农业、畜牧业带来空前影响,在全球杀虫剂市场占有率达25％,然而新烟碱类杀虫剂可以对人类健康产生不利影响,其大量使用导致的食品污染引起了人们更多的关注与研究.目前国内外关于新烟碱类杀虫剂在食品中残留现状的研究调查报道较少,对于新烟碱类杀虫剂在食品中的危害和防治没有系统研究,本文查阅现有的研究文献...     

Detoxification of Synthetic Pyrethroid Insecticides by Thermophilic Microorganisms

Microbially-mediated detoxification of five synthetic pyrethroid insecticides was achieved by a mixed culture growing anaerobically at 75°C. These pyrethroids were hydrolysed to non-insecticidal products after a period of 4–8 weeks' incubation. Of these five permethrin was the most readily transformed and Fastac the most recalcitrant. The mixed culture consisted of a facultative anaerobe and two other obligate anaerobes including a methanogen. This culture was derived from terrestrial sediments from hot-springs in New Zealand. This is the first reported microbial biotransformation of these xenobiotics at a temperature of 75°C. © 1997 SCI.     

Enhancing the potential use of microparticulate insecticides through removal of particles from raw grain

The current study presents the design and evaluation of a laboratory device combining mechanical motion of wheat grain and turbulent air streaming inside a positive pneumatic conveyor system. The device recovers microparticulate nano-engineered alumina insecticide powders (NAIP) from treated grain. The particle removal efficiency of the conveying system was experimentally quantified by using a laboratory prototype assembled by attaching an electrostatic filter (EF) to the conveyors exhaust. Then, the NAIP particles detached from the grain inside the conveyor were drawn by the conveyors’ exhaust air stream into the EF, where particles bound to the electrodes due to electric charge differences. The NAIP particle load bound to the EF electrodes was removed and weighed to determine the efficiency of the wheat grain cleaning process. Our experimental results, under laboratory conditions, show that the recovery efficiency of the prototype averaged 98.0% (±1.4). Thus, the present study provides an innovative strategy to remove NAIP insecticide particles after storage, once their role as insecticide in stored grain has been fulfilled. This technology provides advancement in grain technology allowing the possibility to provide insecticide-free grain to the food market.     

氟碳丙烯酸酯对聚丙烯酰胺的改性

用N-丙基,N-羟乙基全氟辛基磺酰胺(FC)与丙烯酸反应得到了N-丙基,N-羟乙基全氟辛基磺酰胺丙烯酸酯(FCA),再通过与丙烯酰胺共聚得了氟碳改性聚丙烯酰胺P(AM—FCA)。考察了共聚物中FCA单体含量、溶液温度、盐浓度、P(AM—FCA)质量分数对溶液粘度的影响．结果表明．在实验范围内．共聚物溶液的表现粘度随P(AM—FCA)质量分数和盐浓度的增加而增加,随溶液温度和FCA单体含量的增加出现极值,共聚物和聚丙烯酰胺相比,具有良好抗温、耐盐性能,可望作为三次采油用驱油荆。     

Insecticidal effect of thiamethoxam against seven stored-product beetle species

Bioassays were carried out in order to assess the insecticidal value of the neonicotinoid thiamethoxam in different concentrations against seven important beetle species that are major pests of stored grains. These species were Prostephanus truncatus (Horn), Rhyzopertha dominica (F.), Sitophilus oryzae (L.), Sitophilus granarius (L.), Oryzaephilus surinamensis (L.), Tribolium confusum Jacquelin du Val, and Cryptolestes ferrugineus (Stephens). Adults of these species were exposed to grains treated with thiamethoxam at dose rates of 0 (control), 0.01, 0.1, 0.5, 1, 2, 5 or 10 ppm. Our results indicate that with the increase of the insecticide concentration, there was also an increased adult mortality and a reduction in progeny production. To illustrate the relative sensitivity to thiamethoxam of the seven insects, starting with the most susceptible, we can classify them as P. truncatus > R. dominica = S. granarius = S. oryzae > T. confusum = O. surinamensis > C. ferrugineus. The findings of the present research show that thiamethoxam can be recommended for its efficacy at a rate of 10 ppm and duration of 14 days that could be used to control all insects and their progeny.     

我国农药工业现状及问题思考

我国农药工业发展趋势良好。2003年杀虫剂、杀菌剂和除草剂分别达到20．7万t、4．7万t和8．8万t，占农药消费量比例分别为59％．13％和25％。这三种农药的出口量和创汇均远大于进口量和花费的外汇。我国农药出口金额占行业总销售额17.4％。文中从行业管理、产品和产业结构、知识产权、市场、三废处理等方面讨论了我国农药工业发展中存在的问题及解决方法。     

14种农药防治蔗头象虫药效试验初报

本文报道了１４种农药防治蔗头象虫的试验结果。１４种农药均较对照增产增糖亩挽回损失最高在达２８０１ｋｇ，最低为３２０ｋｇ，甘蔗田间锤度增加０．３１－３．０７°Ｂｘ以杀死虫兰珠，甲基异柳磷等１１种农药效果较好，乙敌粉、杀虫双、巴丹３种农药效果较差。