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The drywood termite Cryptotermes brevis (Walker, 1853) (Kalotermitidae) is one of the most important wood structural pest in the world. Substances from the secondary metabolism of plants (e.g., essential oils) have been considered an environmentally safer form of control for urban pests, such as termites. In the present study, we analyzed the lethal and sub-lethal effects of essential oil of Lippia sidoides and its major components on C. brevis pseudergates in two routes of exposure (contact and fumigation). The essential oil of L. sidoides and thymol were more toxic to C. brevis pseudergates when applied by contact (LD = 9.33 and 8.20µgmg, respectively) and by fumigation (LC = 9.10 and 23.6µLL, respectively). In general, treatments changed the individual and collective behaviors of C. brevis pseudergates, as well as the displacement and walking speed. The essential oil of L. sidoides and its major components showed a high potential to control C. brevis pseudergates, due to the bioactivity in the two routes of exposure and the sub-lethal effects on the behavior and walking, important activities for the cohesion of C. brevis colonies.

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The leaf‐cutting ants of the genus Atta are of extreme importance for agriculture and forestry. Few active products can be employed to control these pests and, therefore, the discovery of new insecticidal products represents a fundamental strategy for its management. In this study, we evaluated the mortality, behaviour and locomotion of workers of Atta opaciceps (Borgmeier) exposed to synthesized indole derivatives. The most active compound was 4d [1‐(1H‐indol‐3‐yl)pentan‐1‐one] (LD50 = 0.018 μg/mg), while the 4e [1‐(1H‐indol‐3‐yl)hexan‐1‐one] (LD50 = 3.82 μg/mg) was the least active compound. These two derivatives reduced the survival of A. opaciceps over time and altered the behaviour and locomotion of these ants. This study demonstrates the potential of indole derivatives to produce new formicidal products, since, in addition to being effective, it also affects the ant's behaviour and locomotion.

Pesticides are commonly used to control weeds, diseases, and pests in soybean crops, although natural enemies are also key components of integrated pest management programs protecting soybean from pests. The predatory mite Neoseiulus idaeus Denmark & Muma is commonly found in soybeans associated with tetranychid mites. We determined the compatibility of some pesticides used in Brazilian soybean fields with N. idaeus on the basis of their lethal and sub-lethal effects. We assessed the acute toxicity of pesticides that are considered harmless to females of N. idaeus and evaluated the effects on the mite offspring. Acephate as well as imidacloprid and bifenthrin were most toxic to adult females and were classified as harmful. Chlorfenapyr, indoxacarb, and the neonicotinoid and pyrethroid mixtures were classified as slightly to moderately harmful. Immatures of N. idaeus were able to develop and reach the adult stage when treated with chlorantraniliprole, flubendiamide, glyphosate, and teflubenzuron, but immature survival was reduced to 42 and 64% for offspring of females treated with chlorantraniliprole or teflubenzuron, respectively. Reproduction was most affected in females exposed to chlorantraniliprole and teflubenzuron; these females had daily oviposition rates of 0.5 and 0.4 egg/female/day, respectively, and mean fecundities of 2.7 and 5.8 eggs/female, respectively. On the basis of sublethal effects and life table parameters, chlorantraniliprole was classified as moderately harmful, while the other pesticides tested were classified as harmless. In considering the use of pesticides while targeting the conservation of N. idaeus as a predator of important pests in soybean crops, one must prioritize pesticides that will most likely have less harmful effects on this predator in the field.