Department of Entomology and Plant Pathology, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, Rio de Janeiro 28013-602, Brazil.
Parasit Vectors. 2014 Apr 25;7:198. doi: 10.1186/1756-3305-7-198.
Entomopathogenic fungi are potential candidates for use in integrated vector management, with recent emphasis aimed at developing adult mosquito control methods. Here we investigated the persistence of the fungus Metarhizium anisopliae when tested against female A. aegypti under field conditions.
Black cotton cloths impregnated with M. anisopliae conidia, formulated in vegetable oil + isoparaffin, were maintained on a covered veranda for up to 30 days. At specific times, pieces of the cloths were removed, placed in Tween 80 and the resuspended conidia were sprayed directly onto mosquitoes. The persistence of conidia impregnated on black cloths using three different carriers was evaluated in test rooms. Fifty mosquitoes were released into each room and after a 5 day period, the surviving insects were captured. Another 50 insects were then released into each room. The capacity of the fungus at reducing mosquito survival was evaluated over a total of 35 days.
Conidia extracted from cloths maintained on the veranda for 2 to 18 days remained virulent, with 28 to 60% mosquito survival observed. Mosquito survival following exposure to fungus impregnated cloths showed that fungus + Tween caused similar reductions to that of fungus + vegetable oil. Mosquitoes exposed to the formulation fungus + vegetable oil had survival rates of 36% over the first 5 days of the experiment. Following the release of the second cohort of mosquitoes (6-11days), survival increased to 50%. The survival of the 12-17 day cohort (78%) was statistically equal to that of the controls (84%). Formulation of the fungus in vegetable oil + isoparaffin increased the persistence of the fungus, with the 18-23 day cohort (64% survival) still showing statistical differences to that of the controls (87% survival).
The potential of entomopathogenic fungi for the control of adult A. aegypti was confirmed under field conditions. Vegetable oil + isoparaffin formulations of M. anisopliae significantly increased the effectiveness of the fungus, thus reducing the need for frequent changes of black cloths in residences. Our future aim is to obtain effective control of mosquito populations, with cloths only needing to being replaced once a month.
昆虫病原真菌是综合病媒管理的潜在候选物，最近的重点是开发针对成蚊的控制方法。本研究旨在野外条件下测试真菌绿僵菌对雌性埃及伊蚊的持久性。
用绿僵菌分生孢子和植物油+异链烷烃制成的浸有分生孢子的黑棉布，保存在带顶棚的门廊上长达 30 天。在特定时间，取出布块，放入吐温 80 中，重新悬浮的分生孢子直接喷洒到蚊子上。在测试室内评估了三种不同载体上浸渍黑布的分生孢子的持久性。将 50 只蚊子释放到每个房间，5 天后，捕获存活的昆虫。然后将另外 50 只昆虫释放到每个房间。在总共 35 天的时间里，评估了真菌降低蚊子存活率的能力。
在门廊上保持 2 至 18 天的布上提取的分生孢子仍然具有毒力，观察到 28%至 60%的蚊子存活。用浸渍真菌的布暴露后的蚊子存活率表明，真菌+吐温 80 与真菌+植物油的效果相似。用真菌+植物油处理的蚊子在实验的前 5 天的存活率为 36%。第二批蚊子（6-11 天）释放后，存活率增加到 50%。第 12-17 天组（78%）的存活率与对照组（84%）统计学上相等。真菌在植物油+异链烷烃中的配方增加了真菌的持久性，第 18-23 天组（64%的存活率）与对照组（87%的存活率）仍有统计学差异。
在野外条件下，昆虫病原真菌控制埃及伊蚊成蚊的潜力得到了证实。绿僵菌的植物油+异链烷烃配方显著提高了真菌的效果，从而减少了居民家中频繁更换黑布的需要。我们的未来目标是获得有效的蚊子种群控制，每月只需更换一次布。
