Efeito de iscas formicidas granuladas sobre a biodiversidade de mirmecofauna não alvo em serapilheira de eucalipto

The effect of systematic use of granulated bait for leaf-cutting ants control was assessed on a community of non-target ants in eucalyptus in the municipality of Vera, Mato Grosso State, Brazil. The ants were collected using the Winkler extractors, in 50 samples of 1 m2 of litter in each stage: eight days before the distribution of baits, eight days after the distribution of baits and subsequently each month, totaling 13 collections. Each sample were taken at distances of 50 meters from each other. Copies of ants were assembled via dry, labeled and identified in genus and species level. The analysis of the residual effect was conducted by comparing the number of individuals and species over the months. A total of 273 ants were distributed into nine genera, four subfamilies and 13 species. It was found that diversity index at the end of the study period did not return to initial levels observed before treatment with the ant, suggesting that the active ingredient in bait alters the patterns of diversity pre-existing, causing adverse impact on non-target myrmecofauna. This is the first work in this region and serves as support for future studies on ant diversity in leaf litter of Eucalyptus.Avaliou-se o efeito do uso sistemático de iscas granuladas destinadas ao controle de formigas cortadeiras sobre a comunidade de formigas não-alvo da serapilheira em eucaliptais do município de Vera, Mato Grosso. As formigas foram coletadas, usando o método de extrator de Winkler, em 50 amostras de 1m² de serapilheira, em cada uma das fases: oito dias antes da distribuição das iscas, oito dias depois da distribuição das iscas e posteriormente a cada mês, totalizando 13 coletas. Cada amostra teve distância mínima de 50 m uma da outra. Os exemplares de formicídeos foram montados via seco, etiquetados e identificados em nível de gênero e de espécie. A análise do efeito residual foi realizada pelo comparativo do número de indivíduos e espécies ao longo dos meses. Um total de 273 formigas foi distribuído entre nove gêneros, quatro subfamílias e treze espécies. Constatou-se que o índice de diversidade ao final do período de estudo não voltou aos níveis iniciais encontrados antes do tratamento com o formicida, sugerindo que o princípio ativo da isca formicida altera os padrões de diversidade pré-existentes, causando impacto negativo na mirmecofauna não alvo. Este é o primeiro trabalho realizado na região e serve como subsídio para trabalhos futuros sobre diversidade de formigas em serapilheira de eucaliptos. Effect of formicid granulated baits on non-target antsbiodiversity in eucalyptus plantations litterAbstractThe effect of systematic use of granulated bait for leaf-cutting ants control was assessed on acommunity of non-target ants in eucalyptus in the municipality of Vera, Mato Grosso State, Brazil.The ants were collected using the Winkler extractors, in 50 samples of 1 m2 of litter in each stage:eight days before the distribution of baits, eight days after the distribution of baits and subsequentlyeach month, totaling 13 collections. Each sample were taken at distances of 50 meters from eachother. Copies of ants were assembled via dry, labeled and identified in genus and species level.The analysis of the residual effect was conducted by comparing the number of individuals andspecies over the months. A total of 273 ants were distributed into nine genera, four subfamilies and13 species. It was found that diversity index at the end of the study period did not return to initiallevels observed before treatment with the ant, suggesting that the active ingredient in bait altersthe patterns of diversity pre-existing, causing adverse impact on non-target myrmecofauna. Thisis the first work in this region and serves as support for future studies on ant diversity in leaf litter ofEucalyptus