ABSTRACT Leafcutter ants are a serious pest for forestry plantations and crops in Latin America. They have been traditionally controlled using chemical synthetic pesticides, which are known to have many negative effects to non-target organisms and the environment. Therefore, there is an urgent need for the development of alternative strategies of control, among which the biological control using fungal pathogens is a promising one. We evaluated in laboratory 3 strains of Beauveria bassiana (B5, B6, B7) against workers from 4 to 7 field colonies from 5 species of Acromyrmex leafcutter ant species which are considered pests in the region. Our results showed that all strains were pathogenic, although there are some ant species that turned out to be more susceptible either due to their intrinsic immunity or the natural load of pathogens they carried. The three strains were similarly effective for 3 of the 5 species, A. ambiguus, A. crassispinus, and A. lundii, being responsible for more than 80% of their mortality overriding the effect of their natural pathogens. Only strain B6 was able to kill a similar percentage of ants of A. heyeri, and strain B7 half of them. B5 in A. heyeri, as well as all three strains in A. lobicornis, were responsible for up to 30% of the mortality, but with the additive effect of the pathogens naturally brought by these ants accounted for a 70% of their mortality. We recommend using B6 to test the control of Acromyrmex leaf-cutting ants in the field.

中文翻译：

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白僵菌用于控制切叶蚁：菌株和寄主差异

摘要 切叶蚁是拉丁美洲林业种植园和农作物的严重害虫。它们传统上是使用化学合成杀虫剂来控制的，众所周知，这些杀虫剂对非目标生物和环境有许多负面影响。因此，迫切需要开发替代控制策略，其中利用真菌病原体的生物控制是一种很有前景的方法。我们在实验室中评估了白僵菌的 3 株（B5、B6、B7）对来自该地区被认为是害虫的 5 种 Acromyrmex 切叶蚁的 4 到 7 个田间菌落的工人。我们的结果表明，所有菌株都具有致病性，尽管有一些蚂蚁物种由于其固有的免疫力或它们携带的病原体的自然负荷而变得更易感。这三种菌株对 5 种物种中的 3 种同样有效，即 A. ambiguus、A. crassispinus 和 A. lundii，超过 80% 的死亡率超过了其天然病原体的影响。只有菌株 B6 能够杀死相似比例的 A. heyeri 蚂蚁，菌株 B7 能够杀死一半的蚂蚁。A. heyeri 中的 B5 以及 A. lobicornis 中的所有三个菌株造成了高达 30% 的死亡率，但这些蚂蚁自然带来的病原体的累加效应占了它们死亡率的 70%。我们建议使用 B6 来测试对 Acromyrmex 切叶蚁在田间的控制。只有菌株 B6 能够杀死相似比例的 A. heyeri 蚂蚁，菌株 B7 能够杀死一半的蚂蚁。A. heyeri 中的 B5 以及 A. lobicornis 中的所有三个菌株造成了高达 30% 的死亡率，但这些蚂蚁自然带来的病原体的累加效应占了它们死亡率的 70%。我们建议使用 B6 来测试对 Acromyrmex 切叶蚁在田间的控制。只有菌株 B6 能够杀死相似比例的 A. heyeri 蚂蚁，菌株 B7 能够杀死一半的蚂蚁。A. heyeri 中的 B5 以及 A. lobicornis 中的所有三个菌株造成了高达 30% 的死亡率，但这些蚂蚁自然带来的病原体的累加效应占了它们死亡率的 70%。我们建议使用 B6 来测试对 Acromyrmex 切叶蚁在田间的控制。