Seccacini Emilia, Juan Laura, Zerba Eduardo, Licastro Susana
Centro de Investigaciones de Plagas e Insecticidas (CIPEIN-CITEDEF-UNIDEF (MINDEF/CONICET), Juan Bautista de La Salle 4397, B1603ALO, Villa Martelli, Buenos Aires, Argentina.
Parasitol Res. 2014 Sep;113(9):3355-60. doi: 10.1007/s00436-014-3998-2. Epub 2014 Jul 1.
Natural materials such as beeswax or a paraffin/stearin mixture containing pyriproxyfen and used as a slow release formulation may convert any breeding place into a larvicidal ovitrap for Aedes aegypti (L.) control. Effectiveness and residual activity of beeswax and paraffin/stearin 1:1 discs containing from 10(-5) to 10(-1) % pyriproxyfen and sticked at the bottom of plastic jars were evaluated for adult emergence inhibition (EI) on late 3rd or early 4th instar A. aegypti larvae. At the initial time t = 0, the EI was 100% for vessels containing beeswax or paraffin/stearin 1:1 discs containing up to 10(-4)% pyriproxyfen. For the lowest pyriproxyfen concentration of 10(-5)%, paraffin/stearin mixture gave a higher EI% value than beeswax (100 and 50%, respectively). Jars were kept at room temperature, and water was totally replaced every 15 days. Bioassays for residual activity repeated monthly showed that at 30 days and for pyriproxyfen 10(-5) % and both matrices, the EI values were low and comparable to control values. For pyriproxyfen 10(-4) %, EI remained above 95% for at least 90 days and around 75% up to 180 days. The EI values are always higher for paraffin/stearin mixture than for beeswax. For all other higher concentrations, 100% EI was obtained at least during 300 days. In a semi-field trial, paraffin/stearin/sand O-rings (2:1:2), containing pyriproxyfen 1%, were sunken in 200-l water-storage tanks and held outdoors in a shadow place. After 72 h, a 250-ml aliquot was taken (t = 0) obtaining 100 % EI. Water level was completed to 200 l every 15 days and bioassays repeated monthly as before. Residual activity remains with 100% EI at least for 6 months.
诸如蜂蜡或含有吡丙醚的石蜡/硬脂混合物等天然材料，用作缓释制剂时，可将任何滋生地转变为用于控制埃及伊蚊的杀幼虫产卵诱捕器。评估了含有10⁻⁵至10⁻¹%吡丙醚并粘贴在塑料罐底部的蜂蜡和石蜡/硬脂1:1圆盘对埃及伊蚊三龄后期或四龄初期幼虫成虫羽化抑制（EI）的有效性和残留活性。在初始时间t = 0时，对于含有蜂蜡或含有高达10⁻⁴%吡丙醚的石蜡/硬脂1:1圆盘的容器，EI为100%。对于最低吡丙醚浓度10⁻⁵%，石蜡/硬脂混合物的EI%值高于蜂蜡（分别为100%和50%）。罐子保持在室温下，每15天完全更换一次水。每月重复进行的残留活性生物测定表明，在30天时，对于10⁻⁵%吡丙醚和两种基质，EI值较低且与对照值相当。对于10⁻⁴%吡丙醚，EI至少90天保持在95%以上，直至180天左右保持在75%左右。石蜡/硬脂混合物的EI值始终高于蜂蜡。对于所有其他较高浓度，至少在300天内获得100%的EI。在半田间试验中，将含有1%吡丙醚的石蜡/硬脂/沙子O形环（2:1:2）沉入200升储水箱中，并放置在户外阴凉处。72小时后，取250毫升等分试样（t = 0），获得100%的EI。每15天将水位补充至200升，并像之前一样每月重复进行生物测定。残留活性至少6个月保持100%的EI。
