吡虫啉亚致死剂量对2种色型豌豆蚜生长发育和种群参数的影响

以不同亚致死剂量的吡虫啉分别处理2种色型豌豆蚜,采用实验种群生命表的方法,测定了不同亚致死剂量的吡虫啉处理2种色型豌豆蚜后其F₀及F₁代生长发育和种群参数的变化。结果表明：经处理的2种色型成蚜后,其平均产蚜量均显著低于同色组对照（P<0.05）,平均寿命表现为LC₂₀处理后均显著短于同色组对照（P<0.05）,而LC₁₀和LC₅处理后平均寿命与对照无显著差异,LC₂₀处理后红、绿色型成蚜的平均产蚜量（16.82和 21.44头）和平均寿命（2.84 d,3.60 d）均达到最小值;LC₂₀处理2种色型成蚜后,F₁代若虫期与同色组对照差异不显著,而成虫寿命显著短于同色组对照（P<0.05）,若蚜存活率均高于LC₁₀处理,LC₅处理后F₁代红、绿色型豌豆蚜平均繁殖力均达到最大值81.95头和72.27头;不同亚致死剂量处理后F₁代2种色型成虫产蚜高峰期也存在差异,绿色型均集中在3～7 d,而红色型产蚜高峰期均晚于绿色型;除LC₂₀处理后F₁代绿色型豌豆蚜净增殖率（R₀）（44.22）,平均世代周期（T）（11.29）与同色组对照差异显著外,2种色型豌豆蚜的其余参数在LC₂₀,LC₁₀和LC₅处理下均与同色组对照差异不显著。表明吡虫啉不同亚致死剂量处理2种色型成蚜后,对其F₀代寿命和繁殖力均起到抑制作用,且红色型较绿色型敏感,但对F₁代影响表现为高浓度较低浓度显著。     

Optimizing dosage and preventing leaching of imidacloprid for management of hemlock woolly adelgid in forests

Hemlock woolly adelgid (Adelges tsugae Annand) threatens native hemlock (Tsuga canadensis and T. caroliniana) in the eastern United States. Imidacloprid used as a soil-applied systemic insecticide is effective against A. tsugae in natural forests and in landscapes. Non-target impacts are a special concern because hemlock is ecologically important; often growing next to streams which contain aquatic species that are sensitive to imidacloprid, some of which are protected or endangered fauna. Environmental risk can be mitigated by determining the minimum effective dosage in forests. Adelgid populations responded to imidacloprid dosage with approximately a linear relationship between the percent population reduction (probability scale) vs. log of dosage; 50% reduction in populations could be achieved with 0.15 g per 2.5 cm of trunk diameter at breast height (dbh), or 10% of the maximum labeled dosage. However, effectiveness was found to vary based on dbh; the dosage predicted to give ∼90% reductions in adelgid populations is given by the equation log(dosage) = 0.0153 × dbh − 1.074, where the dosage is g imidacloprid per 2.5 cm of trunk dbh, and dbh is measured as cm. For trees less than 82 cm dbh, these dosages are less than the typical 1.5 g imidacloprid per 2.5 cm dbh currently used. Formulation into tablets rather than as a wettable powder reduced the maximum imidacloprid concentration in soil solution at 5 cm depth from 80 to 1.6 ppm in columns constructed with the organic soil found beneath forest hemlocks. A combination of optimum dosing of trees and adoption of the tablet formulation when treating trees in sensitive habitats should minimize the risk of contaminating aquatic resources with imidacloprid.     

Effects of alternative pesticides on greenhouse whitefly in protected cultivation

The greenhouse trials were conducted to determine the efficacy of environmentally safe insecticides/fungicides with physical mode of action [Agri-50E (propylene glycol alginate, hydrated) and SB Plant Invigorator] against Trialeurodes vaporariorum (Westwood). The efficacy of Agri-50E on adults and nymphs (first, second, third, and fourth instars) was compared to the commercially available standard Boxer 200 SL (imidacloprid) and an untreated control on greenhouse-grown poinsettia. Insecticides were applied by foliar spraying, Agri-50E (2 or 3 ml/l) two times and Boxer 200 SL (1 ml/l) once. Three and 7 days after first application (DAFA), imidacloprid was more effective than both concentrations of Agri-50E in controlling T. vaporariorum adults, whereas 10 DAFA there were no differences between insecticides. Twelve DAFA, imidacloprid was more effective than Agri-50E in controlling first, second and third instars and after 19 days in controlling second, third, and fourth instars. The results obtained from the poinsettia study, indicated that Agri-50E (2 or 3 ml/l) is successful in controlling T. vaporariorum adults and moderately effective against T. vaporariorum immature stages. In the second experiment, the efficacy of Agri-50E on adults was compared to SB Plant Invigorator (SBPI), the standard treatment Calypso 480 SC (thiacloprid), and an untreated control on greenhouse-grown tomato. Agri-50E (3 ml/l) and SBPI (2 ml/l) were applied four times while Calypso 480 SC (0.4 ml/l) was applied twice. The results obtained from tomato study showed that SBPI was the most effective insecticide against T. vaporariorum adults, followed by Agri-50E and Calypso 480 EC. Beside the ecological benefits, the alternative insecticides Agri-50E and SBPI might have an important role to play in future pest management programs.     

粮食作物中残留吡虫啉的提取净化和分析方法

系统综述了在水稻、小麦、玉米等粮食作物中,对残留吡虫啉的提取、净化以及分析方法,这些方法具有简便、快速、准确等特点,各项技术指标均能满足残留检测的要求。     

不同浓度吡虫啉对枸杞果实主要次生物质与枸杞多糖的影响

[目的]探索吡虫啉农药在枸杞生产中的适宜使用方法,为合理使用吡虫啉农药提供科学依据。[方法]在田间条件下研究了10%WP吡虫啉不同浓度及喷药时间对枸杞果实主要次生物质类胡萝卜素、黄酮及多糖、总糖的影响。[结果]不同浓度吡虫啉对枸杞果实次生物质和枸杞多糖含量有显著影响,药后1、7、14 d的黄酮、多糖、总糖含量有依次增加的趋势,类胡萝卜素有降低的趋势。随稀释倍数的增加,黄酮、多糖、总糖含量有增加的趋势,而类胡萝卜素含量有降低的趋势,但都以1 800倍液最高。[结论]吡虫啉10%WP的喷药剂量应以1 800倍液为宜。     

几种药剂对花椒棉蚜防治试验

选用4种杀虫剂,每种3个浓度,对花椒棉蚜进行室内防治试验,结果显示,1.8%阿维菌素乳油和10%吡虫啉可湿性粉剂对蚜虫有较强的杀伤效果。田间防治试验结果表明,上述两种药剂对花椒棉蚜也有相似防治效果,是棉蚜有效的防治药剂。     

山东省桃蚜(Myzus persicae)对啶虫脒、吡虫啉的抗药性

采用浸叶生测法,测定山东省桃蚜5个田间种群(寿光、济南、泰安、烟台、临沂)对啶虫脒、吡虫啉两种常用杀虫剂的敏感性。结果表明:除烟台种群对吡虫啉尚处于敏感状态,山东省供试其他地区的桃蚜种群均对啶虫脒、吡虫啉产生了不同水平的抗性。相对于敏感种群,泰安种群对啶虫脒的抗药性最高,LC50为451.2641mg·L-1,相对抗性倍数为23.63;临沂种群对吡虫啉的抗药性最高,LC50为317.9446mg·L-1,相对抗性倍数为14.40;5个供试桃蚜田间种群对两种杀虫剂均未表现出高等及以上水平的抗药性。在实际防治桃蚜时,应注意与其他作用方式的杀虫剂交替轮换使用。     

Field efficacy and safety of a combination of moxidectin and imidacloprid for the prevention of feline heartworm (Dirofilaria immitis) infection

Throughout the end of March to beginning of May 2006, 212 owned cats and 608 owned dogs from a heavy endemic area for canine heartworm (HW) disease in northern Italy have been examined to assess HW infection prevalence. Both cats and dogs were clinically examined and blood samples were taken from each animal to be examined for HW antibody (Ab). Ab-positive cats were further examined for circulating microfilariae, HW antigens (Ag) and by echocardiography (ECHO) to assess the presence of adult worms. Dogs were clinically examined and blood samples taken from each animal were examined for circulating microfilariae and for HW Ag. Ten cats (4.7%) were found Ab positive. Of these, 6 cats were Ag positive (2.6%) and in 4 (1.8%) the worms were visualized by ECHO. HW prevalence in dogs was 36% (221/608). One hundred and seventy-six (29%) were both microfilaraemic and Ag positive, 40 (7%) had occult infections (no circulating microfilariae) and 7 (1%) were microfilaraemic but Ag negative. Upon owners’ consent, 132 cats (including cats Ab and/or Ag and ECHO positive) were prophylactically treated against HW disease with an imidacloprid/moxidectin spot-on combination (10% imidacloprid/1% moxidectin) monthly administered for 6 months. Cats were re-examined for HW infection in November, 1 month after the last drug administration, and in May–June 2007, 7–8 months after the last treatment. All 122 cats found HW negative before treatment, were found negative at the two examinations at the end of study. The 4 cats Ab positive, 2 cats Ab and Ag positive and 1 Ab, Ag and ECHO positive at the beginning of treatment were found negative. Throughout the treatment, transitory hypersalivation and generic signs of annoyance were reported by owners in 6 cats (4.5%). All signs regressed spontaneously.     

吡虫啉亚致死剂量对桃蚜实验种群的胁迫效应

室内测定了吡虫啉亚致死剂量对桃蚜F0代成蚜的干扰作用,同时通过组建吡虫啉亚致死剂量胁迫下桃蚜F1代的实验种群生命表,利用生命表参数、种群趋势指数（I）以及干扰作用控制指数（IIPC）系统分析了吡虫啉对桃蚜的胁迫效应。结果表明,吡虫啉亚致死剂量对桃蚜室内种群F0代成蚜的胁迫效应主要表现为降低繁殖力与缩短成蚜寿命;对F1代的胁迫效应表现为降低种群的内禀增长率、净增殖率和周限增长率,延长平均世代历期和种群加倍时间,以及压低种群趋势指数。吡虫啉亚致死剂量胁迫下对桃蚜实验种群的干扰作用控制指数均小于1。研究结果说明吡虫啉亚致死剂量对桃蚜具有持续控制作用,不存在刺激桃蚜增殖的现象。     

吡虫啉与联苯菊酯混配对麦长管蚜的毒力及增效作用

参照FAO推荐的浸渍法,研究了吡虫啉与联苯菊酯的5种配比对麦长管蚜的防治效果。结果表明,吡虫啉和联苯菊酯混配后,表现增效作用的配比为1∶1,2∶1,共毒系数(CTC)分别为273.22,126.17;表现相加作用的配比为1∶2,5∶1,共毒系数(CTC)为95.28,104.65;表现拮抗作用的配比为1∶5,共毒系数(CTC)为60.46。5种配比中以1∶1的配比增效作用最强。