Instituto Tecnológico de Veracruz UNIDA, Laboratorio de Genética, Av. Miguel A. de Quevedo #2779, Colonia Formando Hogar, Veracruz, Ver. México C.P. 91897.
J Econ Entomol. 2010 Jun;103(3):570-6. doi: 10.1603/ec09372.
The insecticidal activity after field exposure of an aluminum-carboxymethylcellulose microencapsulated formulation of Bacillus thuringiensis israelensis (Bti) spore-toxin complex, with malachite green as photoprotective agent, was evaluated using third-instar Aedes aegypti (L.) larvae in laboratory bioassays in Veracruz, México. Four insecticide treatments and an untreated control were compared at low and high doses over 96 d of field exposure under full sun or full shade conditions: 1) microencapsulated Bti spore-toxin complex, 2) nonmicroencapsulated Bti spore-toxin complex, 3) a commercial Bti formulation, 4) a commercial formulation of temephos, and 5) an untreated control. The low and high doses corresponded to the LC50 and LC90 concentrations for the Bti insecticides and to 0.5 and 1.0 mg/liter for temephos; the corresponding values for the microencapsulated Bti and commercial Bti, estimated in this study, were 0.061 and 0.14 mg/ml and 0.13 and 0.30 mg/ml, respectively. Overall, the study demonstrated that microencapsulation with aluminum-carboxymethylcellulose improved the activity against Ae. aegypti larvae of B. t. israelensis spore-toxin complex over that of a nonmicroencapsulated spore-toxin complex and that the improvement was particularly important under full sun and high dose. Moreover, insecticidal activity of the microencapsulated B. thuringiensis israelensis spore-toxin complex was superior to that of a commercial B. thuringiensis israelensis formulation and comparable to that of the chemical insecticide temephos. Finally, it was suggested that the microencapsulated B. thuringiensis israelensis formulation should be evaluated for field use in Veracruz because its activity against Ae. aegypti larvae remained high through 31 d and this would allow halving of the current insecticide application frequency.
在墨西哥韦拉克鲁斯的实验室生物测定中，用三龄埃及伊蚊幼虫评估了野外暴露下含微囊化苏云金芽孢杆菌以色列亚种（Bti）孢子毒素复合物和孔雀石绿作为光保护剂的羧甲基纤维素铝微囊化制剂的杀虫活性。在全阳光或全阴凉条件下，经过 96 天的野外暴露，比较了 4 种杀虫剂处理和 1 种未处理对照：1）微囊化 Bti 孢子毒素复合物，2）非微囊化 Bti 孢子毒素复合物，3）一种商业 Bti 制剂，4）一种商业灭多威制剂，5）未处理对照。低剂量和高剂量分别对应 Bti 杀虫剂的 LC50 和 LC90 浓度以及灭多威的 0.5 和 1.0 mg/L；本研究中估算的微囊化 Bti 和商业 Bti 的相应浓度分别为 0.061 和 0.14 mg/ml 以及 0.13 和 0.30 mg/ml。总体而言，该研究表明，用羧甲基纤维素铝微囊化可提高 B. t. israelensis 孢子毒素复合物对埃及伊蚊幼虫的活性，优于非微囊化孢子毒素复合物，在全阳光和高剂量下效果更为显著。此外，微囊化 B. t. israelensis 以色列亚种孢子毒素复合物的杀虫活性优于商业 B. t. israelensis 制剂，与化学杀虫剂灭多威相当。最后，建议评估微囊化 B. t. israelensis 制剂在韦拉克鲁斯的野外使用，因为它对埃及伊蚊幼虫的活性在 31 天内仍然很高，这将使当前杀虫剂的施药频率减半。
