ABSTRACT

The objective of this work was to evaluate the effects of the new neonicotinoid insecticide (clothianidin) on the population of beneficial arthropods in cotton in Brazil. The arthropods evaluated were ladybug (Cycloneda sanguinea), spiders and bigeyed bug (Geocoris sp). The experiment was installed in field conditions and was conducted with Deltapine Ita-90 cultivar, using the design of randomized blocks, with 6 treatments and 4 replicates. The evaluations seeking to verify the mortality of the treatments on the population of these natural enemies in field conditions. The sampling method was plant-shaking. The results showed that the insecticide clothianidin WP, at the doses of 75 and 100 g a.i./ha and clothianidin SC, at the doses of 80 and 100 g a.i./ha caused medium percentages of mortality of the ladybug of 40% one day after the application. To the 14 days after the application, the population of ladybugs was reestablished in all the treatments. For spiders, clothianidin WP at the dose of 100 g a.i./ha caused percentages of mortality of 46%, one day after the application. Clothianidin SC and clothianidin WP at dose of 75 g a.i./ha were selective for spiders. For bigeyed bug, clothianidin WP at the doses of 75 and 100 g a.i./ha and clothianidin SC at the dose of 100 g a.i./ha caused medium percentages of mortality of the bugs of 30% until 7 days after the application. To the 14 days after the application, the population of bigeyed bug was reestablished in all the treatments. Clothianidin SC at the dose of 80 g a.i./ha was selective for the bug.