I examined the impacts of the invasive red imported fire ant (RIFA, Solenopsis invicta) on native ants (Monomorium minimum, Paratrechina sp., S. krockowi, Pheidole metallescens, Forelius pruinosus, and Camponotus americanus) and litter removal in a post oak savannah community in central Texas. The study site was divided into 3 adjacent areas, and ant-toxic bait was used, along with additional colonies of RIFA, to establish 3 different densities of RIFA (naturally occurring, low, and high). I surveyed the ants in the 3 density areas and calculated the catch per unit effort for each species. Litter baits were placed in the 3 density areas for 14 12-hour trials. The masses of the litter removed were measured, and means were calculated for each speciesdensity/ trial/date/period/bait combination. The average amounts of litter removed by RIFA and native ant were different in the 3 density areas (0.42 g, 0.0 g, and 0.75 g for RIFA in the natural RIFA density area, low RIFA density area, and high RIFA density area, respectively; 0.0 g, 0.16 g, and 0.15 g for native ants in the natural RIFA density area, low RIFA density area, and high RIFA density area, respectively), indicating that RIFA does have an effect on native ant habitat use.

This research evaluated the new red imported fire ant (RIFA) bait Advion™. Advion™ contains the active ingredient indoxacarb which, following ingestion, must be metabolized into an N-decarbomethoxyllated metabolite known as JT333 in order to become acutely toxic. Laboratory experimentation was conducted to determine the most effective chemical form and concentration of indoxacarb, as well as the most appropriate grit size, for use in Advion™. The results indicated that Advion™ containing indoxacarb was more effective than Advion™ containing JT333, that 0.10%, 0.06%, and 0.045% were the most effective concentrations of indoxacarb, and that standard sized grit (~2 mm) was more effective than small sized grit (<1 mm). Field experimentation was conducted to determine the most effective concentration and quantity of Advion™, as well as the most effective placement of the bait, for obtaining maximum control of RIFA colonies via individual mound treatments. The results indicated that 10 g (2 Tbsp) of 0.045% Advion™ placed around the mound in a circle with a radius of 0.5-3.0 m was the most effective manner in which to treat individual RIFA mounds. Field experimentation was also conducted to compare the effectiveness of label-rate broadcast treatment with Advion™ to the effectiveness of both label-rate broadcast treatment with Amdro® and pre-baiting broadcast treatment with Advion™. Both pre-baiting broadcast treatment and label-rate broadcast treatment with Advion™ ultimately resulted in 98-99% RIFA colony mortality, which was significantly greater than the 87% colony mortality resulting from broadcast treatment with Amdro®. The 6.2 d LT90 for label-rate broadcast treatment with Advion™ was nearly one half that of the LT90 for pre-baiting broadcast treatment. Laboratory experimentation was conducted to determine whether RIFA workers were capable of metabolizing indoxacarb into the toxic metabolite, and the results clearly indicated that they were. Finally, field experimentation was conducted to evaluate the effectiveness of label-rate broadcast treatment with Advion™ at controlling multiple ant species. The results indicated that label-rate broadcast treatment with Advion™ resulted in control of the RIFA and Pogonomyrmex barbatus for at least 7 wk, and Monomorium pharaonis and Dorymyrmex pyramicus for some period of time between 3 and 7 wk.

Multiple Pseudacteon phorid fly species, including P. tricuspis and P. curvatus, have been released in the southern United States beginning in 1997 and 2003 (respectively) to serve as biological control agents against red imported fire ants Solenopsis invicta Buren (hereafter referred to as RIFA). Field research in the United States on phorid/RIFA interactions has addressed establishment and spread of released species. Additionally, studies are needed on phorid biology and ecology with respect to spatial distribution and phenology, phorid/habitat associations and phorid-mediated affects on RIFA foraging patterns. A suite of manipulative laboratory and field experiments/observations were conducted to 1) develop a novel phorid sampling device to provide uniform and repeatable sampling of flies, 2) assess spatial distributions and phenology of Pseudacteon tricuspis and P. curvatus, 3) assess P. tricuspis and P. curvatus habitat associations and 4) assess phorid-mediated affects on RIFA foraging patterns and caste ratios. PTS Traps (developed for this research) are significantly more effective than previous sampling methods in terms of mean number of flies collected, efficiency of use and % trap success. Data collected with these traps allowed for the determination of patterns of species-specific phenology and relative densities through time and speciesspecific numerical/spatial superiority (Chapter IV). P. curvatus was significantly more abundant than P. tricuspis in only one of the habitat types sampled (df (160) = 4.57, P < 0.005). P. tricuspis densities did not differ significantly among habitat type. Llaboratory experiments revealed that phorid-exposed RIFA colonies foraged less intensively diurnally (df = 1,558; P < 0.05) and more intensively nocturnally (df = 778; P < 0.05) relative to control colonies. Field data regarding this compensatory nocturnal foraging shift did not corroborate those of the laboratory work. In the field there was no significant difference in foraging intensity during nocturnal (df (18) = -0.486, P = 0.633) and diurnal (df (18) = 1.375 P = 0.186) sampling periods. Lastly, chi-square analysis of RIFA forager size-classes revealed significant differences between phorid-infested (treatment) and phorid-free (control) sites (X 2 = 6811.85, df = 3, P < 0.05) with a significantly greater proportion of small RIFA foragers at the phorid-infested site.

Thesis (M.S.) -- Mississippi State University. Department of Entomology and Plant Pathology. / Title from title screen. Includes bibliographical references.

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Phenacoccus solenopsis Tinsley (Hemiptera:Pseudococcidae) has a high morphological diversity, biological adaptations and ecological adjustments that give this species a high capacity to feed host plants. Chemical control is the main method used to control population outbreaks of this mealybug. However, it is difficult to fully control this mealybug with conventional insecticides because of the waxy material that covers the bodies of adult females. The objective of this research was to study the biological aspects of P. solenopsis in cotton leaf discs with and without kaolin. Kaolin is a white clay mineral with various agricultural applications. The film of kaolin particles creates a physical or mechanical barrier of protection against arthropods and pathogens. The work was carried out in the Embrapa Algodão Entomology Laboratory, Campina Grande, State of Paraíba, Brazil, in climatic chamber of type B.O.D. (Biochemical Oxygen Demand), adjusted to a temperature of 25 ± 1 °C, relative humidity of 60 ± 10% and photophase of 12 hours. The experimental design was completely randomized with two treatments and fifty replicates. The treatments consisted of spraying the immature and newly emerged adult stages of P. solenopsis and immersing cotton leaf discs in kaolin suspension (with kaolin) in distilled -1 water at 60 gL the immature stages of P. solenopsis were determined and, in the adult phase, the periods of or in distilled water (control, without kaolin). The duration and survival of pre-oviposition, oviposition, post-oviposition, longevity, fecundity, number of eggs/day, number of eggs/female/day. The parameters of the fertility and life expectancy tables of P. solenopsis were also estimated to determine the population growth potential of this mealybug in both treatments. The results obtained in this research demonstrate that the survival of the immature stages of P. solenopsis in cotton leaves disks was not affected by kaolin. However, it was observed a shorter duration of development of the second and third instars and of the egg period to the adults of P. solenopsis females in the treatment with kaolin suspension and a longer period of oviposition, fecundity and number of eggs per female in that same treatment. In addition, the shortest time required for the P. solenopsis population to double time (TD) associated with the highest values of gross (TBR) and net reproductive rate (Ro), intrinsic (rm) and finite rates of increase (λ), survival, specific fertility (mx), reproductive value (VRx) and life expectancy (ex) in treatment with kaolin suspension indicate that spraying of this product on cotton plants infested by mealybug should be avoided because they favor its growth populational. / A cultura do algodão é bem conhecida do homem desde antiguidade, porém um dos principais problemas dessa a cultura é o ataque de pragas. A cochonilha Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) apresenta uma grande diversidade morfológica, adaptações biológicas e ajustes ecológicos que conferem a essa espécie uma alta capacidade de se alimentar de plantas hospedeiras. O controle químico é o principal método empregado para controlar os surtos populacionais dessa cochonilha. No entanto, é difícil controlar plenamente essa cochonilha com inseticidas convencionais, devido ao material ceroso que recobre os corpos das fêmeas adultas. O objetivo deste trabalho foi estudar os aspectos biológicos de P. solenopsis em discos de folhas de algodão com e sem caulim. O caulim é um mineral de argila branca com diversas aplicações agrícolas. O filme de partículas de caulim cria uma barreira física ou mecânica de proteção contra os artrópodes e patógenos. O trabalho foi conduzido no Laboratório de Entomologia da Embrapa Algodão, município de Campina Grande, Estado da Paraíba, Brasil, em câmaras climatizadas do tipo B.O.D. (Biochemical Oxygen Demand), ajustadas para à temperatura de 25 ± 1 ºC, umidade relativa de 60 ± 10% e fotofase de 12 horas. O delineamento experimental foi inteiramente casualizado com dois tratamentos e cinquenta repetições. Os tratamentos consistiram da pulverização dos estágios imaturos e adultos recém-emergidos de P. solenopsis e da imersão dos discos de folhas de -1 algodoeiro em suspensão de caulim (com caulim) em água destilada a 60 gL destilada, testemunha (sem caulim). sobrevivência dos estágios imaturos de P. solenopsis e, na fase adulta, os períodos de pré- ou em água Foram determinados o tempo de duração e a oviposição, oviposição, pós-oviposição, longevidade, fecundidade, número de ovos/dia, número de ovos/fêmea/dia. Foram também estimados os parâmetros das tabelas de fertilidade e de esperança de vida de P. solenopsis para se determinar o potencial de crescimento populacional dessa cochonilha em ambos os tratamentos. Os resultados obtidos nesta pesquisa demonstram que a sobrevivência dos estágios imaturos de P. solenopsis em discos de folhas de algodoeiro não foi prejudicada pelo caulim. No entanto, observou-se menor duração do desenvolvimento dos segundo e terceiro instares e do período de ovo à adultos de fêmeas de P. solenopsis no tratamento com suspensão de caulim e um maior período de oviposição, fecundidade e número de ovos por fêmea nesse mesmo tratamento. Além disso, o menor tempo necessário para a população de P. solenopsis duplicar em número de indivíduos (TD) associado aos maiores valores das taxas bruta (TBR) e líquida de reprodução (Ro), razões intrínseca (rm) e finita de crescimento (λ), sobrevivência, fertilidade específica (mx), valor reprodutivo (VRx) e esperança de vida (ex) no tratamento com suspensão de caulim, indicam que as pulverizações desse produto nas lavouras de algodoeiro infestadas pela cochonilha devem ser evitadas porque favorecem seu crescimento populacional.

Orientadores: Woodruff Whitman Benson, Jose Roberto Trigo / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-06T14:03:47Z (GMT). No. of bitstreams: 1 Dall'Aglio-Holvercem_ChristianeGoncalves_D.pdf: 1459643 bytes, checksum: 5ed521529fb7303e231df7d9f2ebbda3 (MD5) Previous issue date: 2006 / Resumo: Este trabalho discute alguns aspectos da ecologia da formiga lava-pés Solenopsis invicta e seus parasitóides, as moscas do gênero Pseudacteon (familia Phoridae), e da taxonomia de S. invicta e S. saevissima, ambas nativas da América do Sul. A alometria de colônias de S. invicta no sudeste do Brasil foi estudada através de medições das dimensões do ninho acima do solo, seguidas por escavação e medida da profundidade, biomassa e número de operárias da colônia, assim como da largura média da cabeça das operárias. Análise de regressão dos dados para 28 colônias forneceu novas relações alométricas que podem ser usadas para estimar o volume do ninho (acima e abaixo da superfície do solo), a biomassa de formigas, e o número de operárias a partir do volume do ninho acima do solo. A biomassa de formigas por unidade de volume do ninho, o número de operarias por unidade de volume do ninho, o peso médio por operária, e a largura média da cabeça das operárias foram essencialmente independentes do tamanho da colônia. Em contraste, estas quatro quantidades aumentam com o tamanho da colônia entre colônias de S. invicta na América do Norte. O ciclo sazonal e abundância de moscas parasitóides do gênero Pseudacteon na vizinhança de colônias de S. invicta no sudeste do Brasil foi observado ao longo de um período de 3 anos em li áreas de gramíneas nos arredores de Campinas. O número médio N de forídeos atraídos para um ninho de formigas lava-pés ao longo de um período padrão de observação (15 min) foi usado como uma medida da abundância de forídeos. As dimensões do ninho e algumas variáveis meteorológicas foram também registradas em cada ninho de formigas lava-pés. Pseudacteon tricuspis foi a espécie mais comum (70.4%), seguido por P. curvatus (23.8%), P. obtusus (1.9%) e P.litoralis (3.9%). As características mais notáveis das flutuações sazonais da abundância de Pseudacteon são picos abruptos com duração aproximada de um mês (valores máximos de N entre 4 e 10 forídeos/ninho), que ocorreram em abril e junho de alguns anos; para comparação, valores típicos de N estavam entre 0.2 e 2 forídeos/ninho. As populações de forídeos parecem ser destruídas por incêndios e inundações, mas recuperam-se em uma escala de tempo da ordem de meses. Nenhuma correlação significativa foi encontrada entre a abundância de Pseudacteon e variáveis meteoro lógicas, densidade, ou volume de ninhos de S. invicta, sugerindo que a abundância de Pseudacteon não está diretamente ligada a abundância de S. invicta. Flutuações quase idênticas em abundância de Pseudacteon foram observadas ao longo de um período de 6 meses em duas áreas de estudo separadas por cerca de 3 km, o que pode ser causado por dispersão de forídeos e conseqüente uniformização de densidades sobre áreas de vários quilômetros quadrados. Os números de forídeos atraídos pelos vários ninhos de S. invicta incluídos neste estudo seguiram uma distribuição de Poisson em baixas abundâncias de Pseudacteon (N < 0,5 forídeos/ninho); a distribuição tornava-se mais e mais contagiosa com o aumento da abundância de Pseudacteon (até o máximo observado, de N = 10 forídeoslninho). Esta observação sugere que a atratividade de um ninho de formigas lava-pés aos parasitóides aumenta com o número de forídeos que foram previamente atraídos para o ninho. Critérios quantitativos eficientes foram desenvolvidos para distinguir entre S. invicta e S. saevissima, que são morfológicamente muito similares e cujas distribuições geográficas na América do Sul se sobrepõe significativamente. Estes critérios resultaram da análise de 68 amostras de formigas lava-pés de 9 localidades espalhadas pelo estado de São Paulo (sudeste do Brasil) através de cromatografia gasosa e espectrometria de massa. 22 hidrocarbonetos cuticulares e 18 alcalóides piperidínicos foram identificados nas amostras estudadas, e suas abundâncias relativas foram analisadas utilizando análises de componentes principais e de funções discriminantes. Estas análises mostraram uma separacão nítida entre as duas espécies em um plano com certas coordenadas (P,Q), que são funções das abundâncias relativas dos hidrocarbonetos cuticulares. As amostras provenientes de uma das localidades (São José do Rio Preto) têm uma composição de hidrocarbonetos que é claramente diferente de todas as outras amostras consideradas neste estudo, mas também apresentam algumas caracteristicas em comum com cada uma das duas espécies. Uma possibilidade é que esta população constitua um hibrido de S. invicta e S. saevissima. As duas espécies também exibem uma separação razoavelmente nítida em um plano com coordenadas (R$), que são funções das abundâncias relativas de alcalóides piperidínicos. Os resultados das identificações de espécies baseados nestes critérios de separação quimica concordam com os resultados baseados em um critério morfológico, a presença ou ausência do dente clipeal mediano. A população "anômala" de São José do Rio Preto é morfologicamente classificada como S. invicta / Abstract: This work discusses some aspects of the ecology of the fire ant species Solenopsis invicta and its phorid parasitoid flies ofthe genus Pseudacteon, and ofthe taxonomy of S. invicta and S. saevissima, both of which are native to South America. The allometry of S. invicta colonies in southeast Brazil was studied by measurement of mound (aboveground) dimensions, followed by excavation and measurement of the colony depth, biomass, number of workers, and mean worker head width. Regression anaIysis of data for 28 colonies yielded new allometric relationships which can be used to estimate nest volume (above and below ground), ant biomass, and number ofworkers ITom mound (aboveground) volume. Ant biomass per unit nest volume, number of workers per unit nest volume, mean worker weight, and mean worker head width were nearly independent of colony size. In contrast, these four quantities increase with colony size among S. invicta colonies in North America. The seasonal cycle of abundance of Pseudacteon phorid flies in the vicinity of S. invicta colonies in southeast Brazil was observed over a 3-year period in 11 grass-covered areas in the outskirts of Campinas. The average number N of phorids attracted to a fire ant nest over a standard observation period (15 min) was used as a measure of phorid abundance. Mound dimensions and meteorological variables were also recorded at each fIre ant nest. Pseudacteon tricuspis was the most common species (84.2%), followed by P. curvatus (12.6%), P. obtusus (2.7%) e P. litoralis (0.5%). The most remarkabIe featores of the seasonal fluctuations of Pseudacteon abundance are sharp month-Iong peaks (peak N values between 4 and 10 phorids/nest) which occurred in Abril and June of some years; for comparison, at other times N was typically between 0.2 and 2 phorids/nest. Phorid populations seem to be destroyed by rifes and floods, but recover on a time scale of months. No significant correlation was found between Pseudacteon abundance and meteorological variables, density, or volume of S. invicta nests, suggesting that Pseudacteon abundance is not determined by, and does not determine, the abundance of S. invicta. Almost identical fluctuations in Pseudacteon abundance were observed over a 6-month period in two study areas separated by about 3 km, which may be due to phorid dispersaI and consequent density uniformization over areas of several square kilorneters. The nurnbers of phorids attracted by the various S. invicta nests inc1uded in this study followed a Poisson distribution at 10w Pseudacteon abundances (N < 0.5 phorids/nest), becoming more and more contagious at high Pseudacteon abundances (up to N= 10 phorids/nest). This observation suggests that the attractiveness oftire ant nests to phorid parasitoids increase with the nurnbeer ofphorids which have been previously attracted to the nest. Efficient quantitative criteria were developed for distinguishing between S. invicta and S. saevissima, which are morphologically very similar and whose geographical ranges in South Arnerica significantly overlap. These criteria resulted from the analysis of 68 tire ant samples from 9 localities across São Paulo state (southeast Brazil) via gas chromatography/mass spectrometry. 22 cuticular hydrocarbons and 18 piperidine alkaloids were identified in the studied samples, and their relative abundances were analyzed using principal component and discrirninant function analyses. These analyses showed a sharp separation between the two species in a plane with certain coordinates (P,Q), which are functions of the relative abundances of cuticular hydrocarbons. The fire ant samples from one of the localities (São José do Rio Preto) had a hydrocarbon composition which was markedly different from ali other samples considered in this study, but had some features in common with each ofthe two species. One possibility is that this population constitutes a hybrid of S. invicta and S. saevissima. The two species also show a reasonably sharp separation in a plane with coordinates (R,S), which are functions of the relative abundances of piperidine alkaloids. The species identification results based on these chernical separation criteria agree with those based on a morphological criterion, the presence or absence of the median clypeal tooth. The "anomalous" population from São José do Rio Preto is rnorphologically c1assified as S. invicta / Doutorado / Ecologia / Doutor em Ecologia

The relationship of ant community composition to various habitat characteristics is compared across four habitat types and 12 environmental variables in Mississippi. The four habitat types include pasture, prairie, and oak-hickory forests in the Black Belt and forests in the Flatwoods physiographic region. Ants were sampled using pitfall traps, litter sampling, baiting and hand collecting. A total of 20,916 ants representing 68 species were collected. NMS and ANCOVA both revealed three distinct ant communities (pasture, prairie, and ?forests?) based on species composition and mean ant abundance per habitat type between the four habitat types. Principal component analysis (PCA) partitioned the 12 environmental variation into four axes with eigenvalues >1. Axis 1 differentiated open grass-dominated habitats from woodlands. In contrast axis two mainly separated pastures from prairie remnants. Multiple regression models using the four significant PCA axes revealed that total species richness was significantly affected by variation in the first two PCA axes. Forested sites supported approximately nine more species of ants than prairies and 21 more than pastures. Comparisons of the abundance of ant functional groups were also made between the four habitat types with multiple regression models to investigate how the environmental variables affected certain groups of ants. Annotated notes are included for each ant species encountered during this study.

The importance of abiotic influences on the strength of biotic interactions is largely unknown. To explain large annual fluctuations in the population size of the tropical lizard, Anolis limifrons, on Barro Colorado Island, Panama, I hypothesized that annual variation in lizard population size is the result of modifications in the rate of predation on lizard eggs by Solenopsis ants induced by annual variation in wet season rainfall. I tested this hypothesis by manipulating water availability on experimental plots to Simulate the wettest (HW) and driest (LW) wet seasons in the last twenty years. The mean time to find and attack eggs by Solenopsis ants was significantly shorter on HW plots (range=6.6-21.7 days) than LW plots (range=17.8-30.8 days). Exponential models that regressed time on the cumulative percent mortality indicated that 1) the rate of predation was 3-5 times faster on HW plots than LW plots and 2) the predicted mortality of lizard eggs during their 42 day incubation period was 82.2-95.7% on HW plots and 56.1-58.6% on LW plots. Thus, the amount of rainfall during the wet season affected the population size of A. limifrons by modifying the strength of the interaction between Solenopsis ants and the eggs of A. limifrons. / Master of Science

La biosphère traverse une crise de biodiversité pour laquelle les milieux insulaires sont l’épicentre. Les invasions biologiques y constituent l’un des principaux facteurs de forçage, notamment du point de vue de l’altération des mutualismes, pour le fonctionnement et le maintien des écosystèmes. Durant notre travail en Nouvelle-Calédonie, nous nous sommes intéressés à un groupe clé de voute pour le fonctionnement des écosystèmes, les fourmis, et leur implication vis-à-vis de la dispersion de graines (myrmécochorie). Nous avons réalisé la première identification de plantes autochtones myrmécochores, avec une prépondérance des espèces sur substrats ultramafiques. Puis, nous avons testé la dispersion par les fourmis sur ces substrats. Après avoir caractérisé les communautés selon un gradient de perturbation anthropique, nous avons évalué la dispersion et la contribution des fourmis invasives à ce service par rapport aux fourmis natives. Ainsi, Solenopsis geminata semble capable d'une meilleure dispersion que les espèces natives. A contrario, Wasmannia auropunctata exclue les espèces natives sans assurer de dispersion efficace. Dans le contexte d’un régime de perturbations intense, nos travaux illustrent une communauté néo-assemblée de fourmis, dominée par des exotiques dont certaines pourraient assurer un relai de fonction pour la dynamique des maquis. Nos travaux illustrent la « contexte dépendance » des impacts d’espèces invasives en fonction du niveau de perturbation anthropique. Ils permettent de discuter la contribution possible de ces fourmis pour la restauration après perturbation sur substrats ultramafiques, voire de leur valorisation en ingénierie écologique. / The biosphere is experiencing a biodiversity crisis, which for islands are the epicenter. Biological invasions are there, one of the main drivers, especially regarding the alteration of mutualistic relationships for the functioning and the maintenance of ecosystems. Thus, during our work in New Caledonia, we focused on a key group for ecosystem functions: ants, and their involvement in seed dispersal (myrmecochory). We carried out the first assessment of this mutualism in New Caledonia with the identification of indigenous myrmechorous plants, with a preponderance of species on ultramafic soils. Then, we evaluated the magnitude of seed dispersal by ants on these soils. After the characterisation of ant communities across an anthropic disturbance gradient, we evaluated seed dispersal capabilities of exotic ant compared to native ones. Solenopsis geminata appears to offer a more efficient seed dispersal than natives. On the other hand, Wasmannia auropunctata excludes native species without ensuring effective dispersal. In the context of an intense disturbance regime, our work illustrates a neo-assembled community of ants, dominated by exotic ones, some of which could provide a function relay with respect to maintaining the dynamic of maquis. Our work illustrates the “context dependency” of invasive species’ impacts as a function of anthropogenic disturbance’s level. It also discusses the possible contribution of these ants in a context of restoration after disturbance of habitats on ultramafic substrates, or even their use in ecological engineering program.

Submitted by Reginaldo Soares de Freitas (reginaldo.freitas@ufv.br) on 2018-04-17T13:39:05Z No. of bitstreams: 1 texto completo.pdf: 418759 bytes, checksum: 0fa717dff38084a063271f3027d248e3 (MD5) / Made available in DSpace on 2018-04-17T13:39:05Z (GMT). No. of bitstreams: 1 texto completo.pdf: 418759 bytes, checksum: 0fa717dff38084a063271f3027d248e3 (MD5) Previous issue date: 2015-02-20 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Os inseticidas usados em programas de manejo integrado de pragas devem ser eficazes no controle das pragas e ter baixo impacto sobre organismos não-alvo como os inimigos naturais. Ascia monuste (Lepidoptera: Pieridae) é uma importante praga de brássicas nas Américas. Um importante predador desta praga é a formiga Solenopsis saevissima (Hymenoptera: Formicidae). Assim o objetivo deste trabalho foi selecionar inseticidas a serem usados em programas de manejo integrado de A. monuste. Os inseticidas estudados foram: cartape, ciantraniliprole, flubendiamida, clorantraniliprole, indoxacarbe, clorfenapir, malationa e deltametrina, metomil. Com espinosade, exceção de flubendiamida os demais inseticidas foram eficientes (mortalidade>80%) no controle de A. monuste. Cartape e deltametrina apresentaram as ações mais rápidas de controle da praga (<1h). Malationa e metomil apresentaram os menores períodos residuais de controle (3 dias) enquanto ciantraniliprole e clorfenapir tiveram os maiores períodos residuais de controle (>60 dias). Ciantraniliprole, clorantraniliprole, espinosade e indoxacarbe apresentaram seletividade fisiológica ao predador. Monooxigenases dependentes do citocromo P450, glutationa S-transferases e esterases estiveram envolvidas na seletividade dos inseticidas ao predador. O alto impacto de cartape, clorfenapir, malationa ao predador não diminuiu 22, 11 e 60 dias após as aplicações. Já metomil e deltametrina não causaram impacto ao predador 3 e 5 dias após suas aplicações. / The insecticides used in integrated pest management programs must be effective in pest control and have low impact on non-target organisms such as natural enemies. Ascia monuste (Lepidoptera: Pieridae) is an important pest of brassica in Americas. An important predator of this pest is the ant Solenopsis saevissima (Hymenoptera: Formicidae). Thereby the aim of this work was to select insecticides to be used in integrated pest management programs of A. monuste. The insecticides studied were: cartap, cyantraniliprole, chlorantraniliprole, chlorfenapyr, deltamethrin, spinosad, flubendiamide, indoxacarb, malathion and methomyl. Except for flubendiamide the other insecticides were effective (mortality> 80%) in the control of A. monuste. Cartap and deltamethrin showed the fastest actions of pest control (<1h). Malathion and methomyl had the shortest residual control periods (3 days) while cyantraniliprole and chlorfenapyr had the longest residual control periods (> 60 days). Cyantraniliprole, chlorantraniliprole, spinosad and indoxacarb showed physiological selectivity to the predator. Monooxygenases dependent of the cytochrome P450, glutathione S-transferases and esterases were involved in the selectivity of insecticides predator. The high impact of cartap, chlorfenapyr, malathion to predator not decreased by 22, 11 and 60 days after treatment. The methomyl and deltamethrin did not affect the predator 3 and 5 days after their applications.