ABSTRACT The Cerambycidae Oncideres impluviata (Germar, 1823) is an important insect pest for Acacia mearnsii De Wild in Southern Brazil. The damage caused by their girdling behavior reduces tree productivity, specially in the early years of plant establishment, when girdling is performed on the main trunk of trees. Here, we used a fragment of the mtDNA COI gene to analyze the genetic diversity, population structure and demography of O. impluviata in Southern Brazil, as well as to present the first hypothesis of phylogenetic relationships among species of the genus Oncideres. Our results identified five distinct haplotypes among the populations of O. impluviata, with the most common haplotype identified as O.imp_COI_01. The phylogenetic inferences corroborated the monophyly of O. impluviata with maximum statistical support. In addition, the phylogeny recovered three main population strains that are largely congruent with the haplotype network, which includes two lineages that are found in different edaphic regions of Rio Grande do Sul (Serra do Sudeste and Encosta Inferior do Nordeste). This is the first molecular phylogenetic assessment of O. impluviata. Our findings provide insights into the evolution of a significant species for the Brazilian forestry sector, as well as new resources for planning of pest management strategies. Germar, Germar (Germar 1823 Brazil productivity establishment trees Here diversity O OimpCOI01 OimpCOI imp 01 O.imp_COI_01 support addition network Serra Nordeste. Nordeste . Nordeste) sector strategies 182 OimpCOI0 0 O.imp_COI_0 18 O.imp_COI_ 1 O.imp_COI

Resumo O controle biológico é uma importante ferramenta para o controle de insetos-praga pelas inúmeras vantagens apresentadas e por diminuir os riscos ambientais provocados pelas técnicas de controle químico. No entanto, são escassos estudos referentes à morfofisiologia de microrganismos utilizados nesse método de controle, principalmente no que se refere ao Oncideres impluviata, principal inseto-praga da acácia-negra. Assim, o objetivo do presente estudo foi realizar a caracterização morfofisiológica de isolados de Beauveria bassiana e Metarhizium anisopliae, como uma potencial alternativa para o controle biológico do anelador-da-acácia-negra. Para tanto, foram utilizados cinco isolados de fungos entomopatogênicos (três isolados de Beauveria bassiana e dois de Metarhizium anisopliae) e avaliados o crescimento micelial, esporulação, coloração e caracterização dimensional dos conídios em diferentes meios de cultura (BDA, V8CaCO3 e meio completo). Os isolados de Beauveria bassiana apresentaram melhor crescimento micelial no meio V8CaCO3 e maior esporulação no meio de cultura completo; o micélio aéreo se apresentou de cor branca em todos os isolados. Em relação aos isolados de Metarhizium anisopliae, o maior crescimento micelial e esporulação ocorreram no meio de cultura completo e a coloração do micélio aéreo variou entre tons de cinza e verde-oliva. Esses resultados vêm a gerar informações preliminares a respeito do uso de fungos entomopatogênicos para o controle do anelador-da-acácia-negra.

Abstract Biological control is a useful tool for insect pests control due to the many advantages set out and further to reduce the environmental risks caused by chemical control techniques. However, there is a gap in the scientific literature that describes microorganisms' morphophysiology used in this control method, especially in Oncideres impluviata, the main pest insect of black wattle (Acacia mearnsii De Wild.). Thus, this study aimed to perform morphophysiology characterization of isolates of Beauveria bassiana and Metarhizium anisopliae as a potential alternative for the biological control of twig girdler of black wattle. So, five isolates of entomopathogenic fungi (three isolates of Beauveria bassiana and two of Metarhizium anisopliae) were used. Also, mycelial growth, sporulation, staining was evaluated. Additionally, a dimensional characterization of conidia in different culture media (BDA, V8CaCO3, and complete medium) was carried out. Beauveria bassiana isolates showed better mycelial growth in the V8CaCO3 medium and greater sporulation in the complete culture medium; the aerial mycelium presented a white color in all isolates. These results allow producing preliminary information regarding the use of entomopathogenic fungi for the control of the twig girdler of black wattle.

Abstract In the larval stage, bruchines can cause several damages to the seeds of their host plants due to the consumption of the embryo. The aim of this study was to identify the species of seed-feeding insects in Senna corymbosa (Fabaceae) and quantify the damage caused to seeds. For this purpose, ripe fruits of S. corymbosa were collected monthly from May to August 2014. The fruits were stored in containers to obtain the adult insects and quantify the damage to the seeds. A total of 3,548 seed beetles emerged from the fruits, around 89% belonging to Sennius lateapicalis. Insects consume up to 43.2% of the internal seed content. Moreover, the seed beetles Hymenoptera parasitoids emerged. In this study, seed-feeding insects are recorded for the first time in S. corymbosa. In addition, it contributes to describing fruits and seeds, as well as associated bruchine species and the damage they cause to seeds.

ABSTRACT This study aims to report the occurrence of Heilipus draco in seeds of Ocotea puberula, and to describe the main injuries caused to the seeds and the effects on germination, as well as the occurrence of parasitoid hymenopterans. To this end, fruits of seven trees were selected, in the extreme south of the Atlantic Forest, Brazil. Fruit collection was carried out weekly in the middle third of the canopy, forming lots, from the beginning of fruit formation until total dehiscence, for two years. In order to examine the damage caused by the granivorous insects inside the fruits, 100 fruits were sectioned taking into account the batch/year with the aid of a scalpel and analyzed using a binocular stereomicroscope. In the same way, 144 fruits from each lot/year were stored individually in transparent plates in order to verify the occurrence and identification of species of granivorous insects. The proof of the influence of the injury caused to the seeds by the granivorous insects was carried out by the germination test, with four replications of 25 seeds, comparing seeds with and without oviposition holes. The species H. draco was found to be associated with the fruits of O. puberula. The egg-layings are endophytic, carried out directly on the seed. Larval parasitism of Hymenoptera Bracon, Omeganastatus, Scambus and Triapsis was observed. It is concluded that the cycle from egg to adult takes place inside the seed of O. puberula, and the injuries caused by the larvae decrease germination.

Resumo Utilizar ferramentas moleculares aliadas a técnicas tradicionais de identificação para determinar corretamente as espécies, a diversidade genética e o fluxo gênico de insetos-praga florestais é um dos maiores avanços dos últimos anos. Nesse sentido, o objetivo do trabalho foi realizar o DNA barcoding da espécie Oncideres saga (Dalman, 1823), utilizando o primeiro fragmento do gene mitocondrial Citocromo Oxidase I (COI). Em Seropédica, Rio de Janeiro, galhos de Albizia lebbeck (L.) Benth., anelados por uma espécie de Cerambycidae, foram coletados e armazenados em laboratório sob condições controladas até a emergência dos insetos adultos. Um total de 13 insetos emergiram e, a partir das características morfológicas, foram identificados como Oncideres saga. Oito espécimes adultos foram utilizados para a caracterização molecular a partir do gene mitocondrial Citocromo Oxidase I (COI). Após a obtenção do DNA genômico e amplificação do gene COI via PCR, os produtos foram sequenciados gerando um fragmento com 639 pb. Este é o primeiro estudo molecular que caracteriza o DNA barcoding de Oncideres saga, que é uma espécie geneticamente distinta das demais do gênero Oncideres. Esta pesquisa traz informações básicas que poderão ser utilizadas para explorar novas populações desse inseto-praga em futuros estudos moleculares e aplicados.

Abstract Combining molecular tools with traditional identification techniques to correctly determine species, genetic diversity and gene flow of forest pest insects is one of the greatest advances in entomology in recent years. The aim of this work was to identify the species Oncideres saga (Dalman, 1823) using the first fragment of the cytochrome oxidase I (COI) gene, from the mitochondrial genome. In Seropédica, Rio de Janeiro state, branches of Albizia lebbeck (L.) Benth. ringed by a species of Cerambycidae were collected and stored under laboratory conditions until the emergence of adult insects. Thirteen insects emerged and were identified as Oncideres saga, based on morphological traits. Eight adult specimens were used for molecular characterization of the COI gene. After obtaining the genomic DNA and amplifying the COI fragment via PCR, the products were sequenced, resulting in a fragment of 639 bp length. This is the first molecular study characterizing the DNA barcode of Oncideres. saga, which is a species genetically distinct from the others of the genus Oncideres. This research provides basic information that can be used to explore new populations of this pest insect in future molecular and applied studies.

ABSTRACT This study aims to report two species of Scolytinae that have been damaging Carya illinoinensis trees in southern Brazil. In two Brazilian municipalities, Guarapuava in Paraná State and Pantano Grande in the Rio Grande do Sul State, insects of the Scolytinae family were found damaging pecan trees. Infested tree samples were kept in the laboratory in glass tubes sealed with a voile tissue until the emergence of adults. After the adults’ emergence, the specimens were identified by their morphological characteristics and sent to a taxonomist specialized in Scolytinae family for identification. The species Xyleborus retusus was identified causing damages to pecan trees from Guarapuava while the species Xyleborus ferrugineus was identified in pecan trees from Pantano Grande. Trees injured by these insects displayed similar symptoms in both study areas. In Guarapuava and Pantano Grande, 13 and 10 trees, respectively, died due to stem lesions caused by Xyleborus spp. Thus, this study reports for Brazilian pecan growers the occurrence of Scolytinae species X. retusus and X. ferrugineus damaging C. illinoiensis plants in southern Brazil. It also emphasizes the importance of constant crop monitoring to minimize the risk of pest damage.

ABSTRACT Forest species can have their seeds damaged by granivorous insects, especially by those in their larval stage. In this context, this study aims to report the occurrence of Amblycerus species in Cordia trichotoma seeds, to describe their main damage to seeds and effects on germination, as well as their associated hymenopteran parasitoids. Therefore, seven trees were selected in the municipality of Taquaruçu do Sul, RS, Brazil. Fruits were collected weekly from the medium third of the tree crown, from the beginning of their formation until total dehiscence. To examine the damage caused by granivorous insects within the fruits, 15 fruits from each tree were sectioned with a scalpel. Furthermore, 10 fruits from each tree were stored individually in clear plates to verify the occurrence and identification of granivorous insect species. Evidence of the damage caused to seeds was verified through the germination test by comparing preserved and damaged seeds, with four repetitions of 25 seeds each. The species Amblycerus longesuturalis and Amblycerus profaupar (Chrysomelidae: Bruchinae) were found associated with fruits of C. trichotoma. Female insects predominantly laid eggs on the superior part between the marcescent calyx and the fruit, and larvae perforated the fruit tegument to start consuming seed embryos and reserves. Bruquine larvae are parasitized by Hymenoptera of Bracon, Mirax, Omeganastatus and Triapsis genera. In conclusion, the germination of C. trichotoma seeds is significantly affected by emergence orifices caused by granivorous species.

ABSTRACT The objective of this study is to evaluate the damage caused by Acromyrmex heyeri Forel, 1899 and Acromyrmex lobicornis Emery, 1887 to Pinus taeda L. seedlings during the first two months after replanting. The experiment was conducted in the company Bosques del Plata, located in the province of Corrientes, Argentina. The evaluations were carried out at seven, 14, 21, 36, 50 and 65 days after replanting the seedlings, when the number of dead, alive, non-attacked, alive deneedled, and alive deneedled with cuts/damage to the apical bud by leaf-cutting ants was quantified. The results allow us to conclude that A. heyeri and A. lobicornis are responsible for losses to the order of 20.8% of the seedlings in an initial P. taeda stand at 65 days. The damage caused to seedlings by the two leaf-cutting ant species is constant over time, in which A. lobicornis is more voracious than A. heyeri.

RESUMO As áreas plantadas com nogueira-pecã Carya illinoinensis (Wangenh.) K. Koch (Juglandaceae) vêm crescendo em todo o Brasil, principalmente na região Sul. Com isso aumentam os riscos de incidência de pragas e doenças. Assim, o presente estudo objetivou revisar aspectos importantes relacionados à cultura da nogueira-pecã, com ênfase nas espécies-praga e espécies benéficas de artrópodes, relatadas na sua região de origem e no Brasil. A partir do levantamento bibliográfico notam-se poucos registros de espécies-praga nocivas à cultura, grande parte, 18 espécies, são registradas para o Rio Grande do Sul, constituindo-se como uma ínfima parcela quando traçado um comparativo com as espécies já registradas e estudadas nos Estados Unidos, país de origem da espécie Carya illinoinensis, que soma mais de 66 espécies-praga, entre insetos e ácaros. Dentre as espécies-praga que merecem destaque estão o pulgão Monellia caryella, as espécies de filoxeras Phylloxera devastatrix e Phylloxera notabilis, pois são espécies que ocorrem tanto no Rio Grande do Sul, quanto nas regiões de origem da nogueira-pecã, causando danos às folhas das plantas. Ao mesmo tempo que se verifica uma alta diversidade de espécies-praga para a pecanicultura, é possível observar, tanto nos Estados Unidos quanto no Brasil, especialmente no Rio Grande do Sul, uma gama de potenciais predadores e parasitoides das espécies nocivas à Carya illinoinensis. Portanto, sugere-se a utilização do Manejo Integrado de Pragas, com estudos futuros que priorizem a manutenção de agentes de controle biológico existentes nas áreas de plantio, buscando garantir nozes de qualidade e em quantidade satisfatória, preservando a saúde do consumidor e do pomar.

ABSTRACT The areas cultivated with pecan, Carya illinoinensis (Wangenh.) K. Koch (Juglandaceae), have been growing mainly in the southern region of Brazil. Along with it, the risks of diseases and plagues rise. Thus, the present study aimed at revising important aspects of the pecan culture, with an emphasis at plague species and beneficial species of arthropods related to their original region and in Brazil. From a bibliographical survey, a few records about plague-species harmful to the culture are found, from which, 18 species, are registered in Rio Grande do Sul, being a very small number when compared to the species already registered and studied in the United States, the original country of the Carya illinoinensis species, which are more than 66 plague-species, among insects and mite. Among the plague-species which deserve attention are the mite Monellia caryella, the species of phylloxera Phylloxera devastatrix and Phylloxera notabilis, because they are species that happen to be registered in both in the United States and the original regions of pecan tree, causing damage to the plant leaves. At the same time a high diversity of plaguespecies harmful to the pecan culture is found, it is possible to observe both in the United States and in Brazil, especially in the state of Rio Grande do Sul, a variety of potential predators and parasitoids to the harmful species to Carya illinoinensis. Thus, Integrated Pest Management (IPM) is suggested, with further studies that prioritize the maintenance of biological control agents existing in the planting area, searching to ensure nuts in quality and satisfactory amount, preserving the consumer and the orchard health.

ABSTRACT This work aimed to characterize the composition of the soil macrofauna in non-mined and mined areas recovered with native vegetation, Eucalyptus dunnii Maiden and Acacia mearnsii De Wild. plantations, in a coal mine. Five areas were evaluated, namely, three non-mined areas and two mined and recovered areas. Six soil samples per area were collected using a 10x10 cm circular probe, every month during one year. Defragmentation of the soil and removal of specimens was carried out in a laboratory. A total of 3,195 specimens from 11 taxa were collected. The most abundant groups were Hymenoptera, Isoptera and Coleoptera. There were significant correlations (p<0.05) between the total abundance of Isoptera and Coleoptera with some meteorological variables. The recovery process of the mined areas with black-wattle and eucalyptus plantations proved to be efficient because there was similarity of macrofauna groups between the non-mined, mined and native vegetation areas.

Abstract Heteropsylla caldwelli Burckhardt (Psyllidae, Ciriacreminae) is reported for the first time from Brazil (States of Minas Gerais, Paraná, Rio Grande do Sul) from Enterolobium contortisiliquum (Vell.) Morong. The earpod tree, from Albizia edwallii (Hoehne) Barneby and J.W. Grimes and Senegalia polyphylla (DC.) Britton (Fabaceae, Mimosoideae), all previously unknown hosts. The population dynamics of the psyllid were investigated in a seven-year-old plantation of E. contortisiliquum in an abandoned open-pit coal mine in Candiota, Rio Grande do Sul during two years. The population showed peaks in spring and summer, correlating directly with the mean air temperature and the population size of microhymenoptera.

Resumo: O objetivo deste trabalho foi avaliar a composição da mesofauna do solo em áreas não mineradas e mineradas, sob recuperação ambiental com vegetação nativa e silvicultura, em mina de carvão mineral no Sul do Brasil. Cinco tratamentos foram avaliados: vegetação nativa em área não minerada; plantação de Acacia mearnsii em área não minerada; plantação de A. mearnsii em área minerada; plantação de Eucalyptus dunnii em área não minerada; e plantação de E. dunnii em área minerada. Durante um ano, quatro amostras de solo foram retiradas mensalmente, por tratamento. Os organismos foram extraídos com uso de funil de Berlese e luz incandescente de 50 W. Foram coletados 23.911 organismos da mesofauna do solo, identificados e distribuídos em 13 grupos taxonômicos. A abundância de espécimes foi similar entre os tratamentos. A maior diversidade de grupos taxonômicos foi encontrada sob plantação de A. mearnsii, em área minerada, e nas plantações de E. dunnii em área não minerada e minerada, todas com 13 grupos. Eucalyptus dunnii e A. mearnsii auxiliam na mitigação dos impactos da mineração de carvão sobre a diversidade dos grupos taxonômicos da mesofauna do solo, pois a composição dos mesoartrópodes é semelhante à das áreas que não foram diretamente afetadas pelos efeitos da mineração.

Abstract: The objective of this work was to evaluate the soil mesofauna composition in non-mining and in mining areas under environmental recovery with native vegetation and forest planting, in a coalmine in Southern Brazil. Five treatments were evaluated: native vegetation in non-mining area; plantation of Acacia mearnsii in non-mining area; plantation of A. mearnsii in mining area; plantation of Eucalyptus dunnii in non-mining area; and plantation of E. dunnii in mining area. Four soil samples per treatment were collected monthly, during one year. The organisms were extracted using a Berlese funnel with 50-W incandescent light. A total of 23,911 organisms were collected from the soil mesofauna, which were identified and distributed into 13 taxonomic groups. The abundance of specimens was similar between treatments. The greatest diversity of taxonomic groups was found under A. mearnsii plantation, in the mining area, and under E. dunnii plantations in non-mining and mining areas, all with 13 groups. Eucalyptus dunnii and A. mearnsii help to mitigate the impact of coal mining on the diversity of the soil mesofauna taxonomic groups, since the composition of mesoarthropods is similar to that of areas that have not been directly affected by mining.

RESUMO Os escolitíneos (Curculionidae, Scolytinae) são besouros broqueadores, pertencentes à ordem Coleoptera que se desenvolvem no interior de árvores. Em países do hemisfério norte, estes insetos causam prejuízos significativos, principalmente quando ocorrem em surtos epidêmicos. No Brasil, em geral, os danos causados são menores quando comparados aos do hemisfério norte. Tendo em vista a importância da subfamília Scolytinae, este trabalho tem por objetivo proporcionar um melhor entendimento do comportamento destes, principalmente no que tange à altura de voo em povoamento de Pinus taeda L.. Para tanto, foram instaladas 72 armadilhas de interceptação de voo, em área pertencente à Fundação Estadual de Pesquisa Agropecuária (FEPAGRO), localizada em Santa Maria, Rio Grande do Sul. As armadilhas foram distribuídas em diferentes alturas (tratamentos) com três repetições distantes 30 metros entre si. Os tratamentos corresponderam às alturas de 0,5; 1,0; 1,5; 2,0; 2,5; 3,0; 3,5; 4,0; 4,5; 5,0; 5,5 e 6,0 metros. Foram capturados: Hypothenemus eruditus em maior abundância na faixa de 1,0 a 1,5 metros; Xyleborus ferrugineus, Xyleborinus gracilis e Xyleborus affinis a 0,5 metros; Xyleborinus saxeseni e Xylosandrus retusus não apresentaram preferência de altura de voo. Conclui-se que o intervalo situado entre 0,5 e 1,5 metros é ideal para analisar quantitativamente os escolitíneos associados ao Pinus taeda.

ABSTRACT Scolytids (Curculionidae, Scolytinae) are small borer beetles belonging to the order Coleoptera that develop within or under the bark of trees. In northern countries, these insects cause significant damage especially when outbreaks occur. In Brazil, in general, the damage is minor when compared to the northern hemisphere. Given the importance of subfamily Scolytinae, this paper aims at providing a better understanding of the behavior of Scolytids, mainly regarding the flight height in a stand of Pinus taeda L. For the execution of this work 72, intercept flight traps were installed in area belonging to the State Foundation for Agricultural Research (FEPAGRO), located in Santa Maria, Rio Grande do Sul state. The treatments correspond to heights of 0.5; 1.0; 1.5; 2.0; 2.5; 3.0; 3.5; 4.0; 4.5; 5.0; 5.5 and 6.0 meters. It was possible to capture: Hypothenemus eruditus in greater abundance at the range of 1 to 1.5 meters; Xyleborus ferrugineus, Xyleborinus gracilis and Xyleborus affinis to 0.5 meters; Xyleborinus saxeseni and Xylosandrus retusus with no preference. It is concluded that the range between 0.5 and 1.5 meters is ideal to analyze quantitatively the scolytids present in the Pinus taeda.

RESUMO O estudo objetivou avaliar a eficiência de inseticidas no controle de Thaumastocoris peregrinus em laboratório. Para tanto, 15 plantas de Eucalyptus dunnii receberam aplicações a campo de: imidacloprido - 78,8 (g/ha), tiametoxam - 37,5 (g/ha), lambda-cialotrina+tiametoxam - 21,2+25,8 (g/ha), lambda-cialotrina - 24,9 (g/ha), e somente água (testemunha). Para determinar a eficiência dos inseticidas, utilizou-se o teste de confinamento, onde folhas de E. dunnii foram pulverizadas uma única vez, e em seguida, coletadas em dois períodos distintos. Em laboratório, foram utilizadas oito folhas para ninfas e oito para adultos, por tratamento, individualizadas em placas de petri; cada repetição recebeu 10 exemplares da espécie. As avaliações da sobrevivência foram realizadas no segundo, quarto, vigésimo segundo e vigésimo quarto dias após a aplicação dos tratamentos (DAT). Conclui-se que os inseticidas testados, nas suas respectivas doses, apresentam eficiência de controle de ninfas e adultos de T. peregrinus.

ABSTRACT The study aimed to evaluate the control efficiency of insecticides on Thaumastocoris peregrinus in the laboratory conditions. Therefore, 15 plants of Eucalyptus dunnii received the follow field spray: imidacloprid (78.8g ai / ha), thiamethoxam (37.5g ai / ha), lambda-cyhalothrin + thiamethoxam (21.2 + 25.8g ai / ha), lambda-cyhalothrin (24.9g ai / ha), and the untreated control only water. To determine the insecticides efficiency, we used a containment test, with E. dunnii leaves sprayed and collected at two different times. In the laboratory was used eight reps of leaves to adult and eight to nymphs by treatment individually placed in petri dishes; each repetition received 10 insect specimens. Assessments of alive insects were carried out at second, fourth, twentieth, twenty-fourth days after spray treatment (DAT). We conclude that the insecticides tested, on respective rate, presented efficient control of T. peregrinus nymphs and adults.

RESUMO A cultura do eucalipto tornou-se uma importante atividade econômica no Brasil, no entanto, com o aumento das áreas de plantio, os problemas entomológicos tendem a aumentar nas mesmas proporções. Neste sentido, torna-se necessário o constante monitoramento dos insetos associados a esses sistemas de plantios homogêneos, buscando o desenvolvimento de programas de manejo integrado de pragas. Assim, o objetivo deste trabalho foi o levantamento populacional da entomofauna associada a plantios de Eucalyptus spp., em São Francisco de Assis - RS. As coletas foram realizadas por meio de armadilhas luminosas no período de julho de 2008 a agosto de 2009, em talhões de três anos de idade, com as espécies: Eucalyptus dunnii, Eucalyptus grandis e Eucalyptus grandis x Eucalyptus urophylla. Os insetos coletados foram analisados através dos índices de frequência, abundância, constância e diversidade. Realizou-se ainda a correlação entre as espécies-praga identificadas e as variáveis meteorológicas do período. Foram coletados 3.623 indivíduos distribuídos em oito ordens (Blattodea, Coleoptera, Dermaptera, Hemiptera, Hymenoptera, Lepidoptera, Mantodea e Odonata), identificando-se três espécies e três gêneros de lepidópteros desfolhadores considerados de importância econômica: Automeris illustris, Eupseudosoma sp., Sabulodes sp., Sarsina sp., Thyrinteina arnobia e Agrotis ipsilon. e a coleobroca Phoracantha semipunctata. Pelos resultados obtidos, pode-se concluir que existem espécies-praga importantes da cultura de Eucalyptus já estabelecidas na região, necessitando, portanto, de monitoramento constante para que estas espécies não ocasionem danos aos plantios.

ABSTRACT The cultivation of eucalyptus has become an important economic activity in Brazil. However, with the increase of the plantation areas, some entomological problems tend to increase in the same proportion. The constant monitoring of the insects associated with homogeneous planting systems is very important in order to seek the development of programs for integrated pest management. Thus, the purpose of this study was to perform a survey on the insect populations associated with Eucalyptus spp., in São Francisco de Assis, RS. The collects were carried out by light traps from July 2008 to August 2009 in three-year-old stands with the species: Eucalyptus dunni, Eucalyptus grandis and Eucalyptus grandis x Eucalyptus urophylla. The insects collected were analyzed using the faunistic indices, frequency, abundance, diversity, and constancy. The correlation between the pest species identified and the meteorological variables for the period were also performed. We collected 3623 individuals belonging to eight orders (Blattodea, Coleoptera, Dermaptera, Hemiptera, Hymenoptera, Lepidoptera, Mantodea and Odonata). Three species and three genus of lepidoptera defoliators considered of economic importance were identified: Automeris illustris, Eupseudosoma sp., Sabulodes sp., Sarsina sp., Thyrinteina arnobia and Agrotis ipsilon as well as the borer Phoracantha semipunctata. Our results show that there are important pest species of Eucalyptus already established in the region therefore some constant monitoring is required so that these species do not cause damage to plantations.