Abstract:

Objective　The efficacy of fipronil baits against Solenopsis invicta was determined and the technical specifications for application of the baits were developed. Methods　A combination of small?scale field experiments and single nest experiments was used. Results　The  results  of  small?scale  field  experiments  using  the  three  concentration  gradients, 0.0005%, 0.005% and 0.05%, showed that the 0.05% fipronil baits had the best killing effect, which was evident beyond 3 d after application on a dose of 6 g for each ant nest in the experiment areas. The adjusted decrease rate of active ant nests was 9.52%, and that of worker ants was 43.94%. Significant control effects were observed beyond 6 d after application of the baits, the adjusted decrease rate of active ant nests being 74.03% and that of worker ants 98.05%. At day 27 and 30, both decrease rates reached 100%. Additionally, the baits had no obvious effect on any other arthropod. The results of single nest experiments showed that the optimal dosage of the 0.05% fipronil baits for 25-30 cm mature nests was 5 g/nest. It was shown that the active time of feeding for S. invicta was beyond 17:00 in summer and from 9:00 to 17:00 in winter. Evenly spraying the baits on the surface of ant hills would contribute to the shortest time for worker ants to deposit the baits. Conclusion　The 0.05% fipronil baits can rapidly and completely kill S. invicta  ants  while  sparing  non?target  arthropods. The  technical  specifications  for  application are as follows: based on the recognized optimal dosage, 5 g/nest, for 25-30 cm mature nests, the actual application amount can be adjusted according to the size of nest. The optimal application time was after 17:00 in summer and from 9:00 to 17:00 in winter. The best way to apply the baits is by evenly spraying them on the surface of ant hills.

Key words: Solenopsis invicta, Fipronil, Bait, Application method

摘要：

目的　观察氟虫腈饵剂对红火蚁的防控效果，并制定其施用技术规范。方法　采用野外小区试验和单蚁巢试验相结合的方法。 结果　0.0005％、0.005％、0.05％ 3个浓度梯度的小区试验结果表明，0.05％氟虫腈饵剂的杀灭效果最理想，供试小区内每巢投药量6 g， 施药3 d 后即可见效， 活动蚁巢校正减退率为9.52％， 工蚁校正减退率为43.94％； 施药6 d后即可达到明显的控制效果，活动蚁巢校正减退率为74.03％，工蚁校正减退率为98.05％；施药27和30 d后，工蚁减退率和活动蚁巢减退率均达到100％，并且该药剂对其它节肢动物类群没有明显影响。单蚁巢试验结果表明，0.05％氟虫腈饵剂对25～30 cm成熟蚁巢的最适施药量为5 g/巢，夏季红火蚁取食活跃时间为17：00以后，冬季为9：00－17：00，将饵剂均匀撒施在蚁丘表面的施药方式工蚁搬运时间最短。结论　0.05%氟虫腈饵剂具有作用快速，杀灭彻底，对非靶标节肢动物安全的特点。其施用技术规范为25～30 cm的成熟蚁巢的最适施药量为5 g/巢，并应以此为标准视蚁巢大小增减施药量，夏季最适施药时间为17：00以后，冬季为9：00－17：00，最佳施药方式为将饵剂均匀撒施在蚁丘表面。

关键词: 红火蚁, 氟虫腈, 饵剂, 施用技术