The sugarcane borer, Diatraea saccharalis (Fabricius), is the major pest insect attacking sugarcane crops in Brazil. Population control by insecticide treatment is not efficient due to simultaneous presence of all developmental stages of the insect throughout the year, and alternative control methods are needed. Two female-produced sex pheromone components, (Z,E)-hexadeca-9,11-dienal and (Z)-hexadec-11-enal, have previously been reported to elicit antennal activity and behavioral response of males in flight tunnel experiments. However, the attractiveness of these compounds in field tests has been very low. In this study, two additional female-produced compounds in D. saccharalis eliciting consistent antennal response in males were identified as (Z)-hexadec-9-enal and hexadecanal. In flight tunnel assays, the behavioral response to a quaternary blend was significantly higher when compared with the previously identified binary blend. Subtracting (Z)-hexadec-9-enal or hexadecanal from the full blend did not reduce attraction, indicating redundancy in the communication channel. We conclude that additional compounds are part of the sex pheromone of D. saccharalis, which may improve the efficiency of trap lures for monitoring of this pest.

ABSTRACT A bilateral gynandromorph of Spodoptera frugiperda was reported for the first time from Minas Gerais State, Brazil. The specimen with this trait was found among the progeny of a laboratory rearing population and exhibited dimorphism in the antennae, wings, head, thorax, and abdomen. It had a male left side and a female right side. Both the external and internal genitalia were typically those of a male.

Toxorhynchites mosquitoes play important ecological roles in aquatic microenvironments, and are frequently investigated as potential biological control agents of mosquito disease vectors. Establishment of Toxorhynchites laboratory colonies can be challenging because for some species, mating and insemination either do not occur or require a prohibitive amount of laboratory space for success. Consequently, artificial insemination techniques have been developed to assist with mass rearing of these species. Herein we describe an adapted protocol for colony establishment of T. theobaldi, a species with broad distribution in the Neotropics. The success of the technique and its implications are discussed.

El monitoreo de machos de minador del café Leucoptera coffeella (Guérin-Méneville) (Lepidoptera: Lyonetiidae), fue evaluado utilizando trampas cebadas con feromonas sexuales. Se realizaron evaluaciones de las poblaciones de los machos de L. coffeella y del porcentaje de hojas minadas y huevos en siete cafetales, localizados en la región del Triángulo Mineiro y en la Zona da Mata, MG, Brasil. El periodo de evaluación varió entre 6 a 20 meses. Se verificó la variación de las capturas de machos entre las diferentes regiones. Para el Triángulo Mineiro se encontró una relación positiva entre la captura de machos y el porcentaje de hojas minadas (R² = 0.79). Para la Zona da Mata esta relación fue significativa, aunque baja (R² = 0.06). En esta última región, también se observó una relación significativa entre la captura de machos y los huevos de esta plaga (R² = 0.34). De las variables climáticas analizadas, la reducción de temperatura promedio favoreció la infestación de los cafetales y la captura de los machos. Los resultados de este estudio sugieren que existe una relación significativa entre la captura de machos y la densidad poblacional de L. coffeella. Por lo tanto, se recomienda el uso de estas trampas con feromonas sexuales para el monitoreo del minador del café.

The use of pheromone traps was tested for monitoring males of the coffee leaf miner, Leucoptera coffeella (Guérin-Méneville) (Lepidoptera: Lyonetiidae). Insect sampling was carried out in seven coffee plantations under different agronomic conditions in the two regions - Triángulo Mineiro and Zona da Mata, MG, Brazil. The sampling period ranged from 6 to 20 months. The locality significantly affected male capture. Among the weather variables analyzed, the decrease in the average temperature favored higher infestations of L. coffeella in coffee plants and higher male capture. A positive relation between male capture and percent of leaves mined (R² = 0.79) was observed in the Triángulo Mineiro while in Zona da Mata this relationship was weak, although significant (R² =0.06). In this last region, a positive and significant correlation between males captured and pest eggs was observed (R² = 0.34). The results of this study suggest that there is a significant correlation between the male capture by pheromone traps and the population density of L. coffeella, emphasizing the potential of pheromone traps for monitoring the coffee leaf miner.

Triatoma brasiliensis Neiva é o principal inseto vetor da doença de Chagas no Nordeste do Brasil. Os adultos da espécie apresentam dois pares de glândulas exócrinas, as glândulas metasternais e as glândulas de Brindley que liberam compostos voláteis, possivelmente com função de defesa, alarme e/ou acasalamento. O conhecimento anatômico e histológico das glândulas de Brindley e metasternal no gênero Triatoma é escasso e, considerando a relevância dessas glândulas na sua biologia, o objetivo do presente trabalho foi estudar e conhecer a sua morfologia. As glândulas de Brindley e metasternal de T. brasiliensis possuem uma unidade glandular similar àquela descrita para Rhodnius prolixus Stål e Panstrongylus megistus Burmeister, formada principalmente por um aparato secretor, sáculo e ducto coletor.

Triatoma brasiliensis Neiva is the most important vector of the Chagas' disease in the semiarid zones of North-eastern Brazil. Adult bugs have two main pairs of exocrine glands, the metasternal and the Brindley's glands, which release volatiles possibly with defense, alarm and/or mating functions. To date, anatomical and histological studies of the metasternal and the Brindley's glands in the genus Triatoma are scarce and, considering the relevance of these exocrine glands, the present work aimed at studying their morphology in T. brasiliensis. The metasternal and the Brindley's glands of T. brasiliensis consist of glandular units similar to those described for Rhodnius prolixus Stål and Panstrongylus megistus Burmeister, comprising a secretory apparatus, saccule and collector duct.

Pheromones are chemical compounds used by species to communicate intra and inter specifically. As strategy of integrated pest management (IPM), the use of these compounds allows the monitoring of target insects that results in more reliable interventions and consequently avoiding unnecessary use of pesticides. In certain crops these compounds are used as a control measure, not only monitoring. The Brazilian agriculture has a portfolio of 49 major crops that are attacked by 447 species of insects. Of this total, 103 species have already been the subject of study in the research with pheromones. Currently, in the Brazilian market, 28 pheromone products are indicated for the control of 19 insect pests. However, these products are not used regularly in major crops of the country. This stems from the lack of implementation of IPM of these crops. While the research focused on the main species of agribusiness pests, marked of pheromones products is serving to more marginal crops like apples and peaches at the expense of major crops like soybean and corn.

Objetivou-se determinar o efeito da defesa da presa Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) na taxa de predação por fêmeas de Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae). Podisus nigrispinus, predou 1,0; 1,4; 1,2; 3,8; 3,0 lagartas de terceiro estádio de S. frugiperda com defesa, respectivamente, nas densidades de uma, duas, quatro, seis e oito lagartas, enquanto esses valores foram de 0,4; 0,8; 1,6; 2,8; 3,2 lagartas sem defesa, respectivamente, nessas densidades. A taxa de ataque (a) e o tempo de manipulação (Th) foram, respectivamente, de 0,67 ± 0,39-h e 6,72 ± 2,88 horas para fêmeas de P. nigrispinus alimentadas com lagartas com defesa e de 2,51 ± 0,16-h e 0,51 ± 0,77 horas para aquelas sem defesa. A resposta funcional do predador P. nigrispinus varia com a defesa e a densidade da presa S. frugiperda, com maior consumo de presas sem defesa em altas densidades.

The effect of the defense of the prey Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) on predation rates of Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) females was studied. P. nigrispinus preyed 1.0, 1.4, 1.2, 3.8 and 3.0 and 0.4, 0.8, 1.6, 2.8 and 3.2 third instars of S. frugiperda larvae with and without defense, respectively, with the densities of one, two, four, six and eight larvae. The attack rate and the manipulation time were, respectively, 0.67 ± 0.39-h and 6.72 ± 2.88 h for P. nigrispinus females fed with larvae with defense and 2.51 ± 0.16-h and 0.51 ± 0.77 h for those without defense. The functional response of the predator P. nigrispinus varies with the defense and the density of the prey S. frugiperda, with larger consumption of prey without defense at higher densities.

Este trabalho demonstra a viabilidade da utilização de vidros porosos como materiais para armazenar e liberar feromônios de insetos, visando o controle de pragas na agricultura. Feromônios de diferentes insetos foram impregnados em vidros porosos do tipo Vycor (PVG), e o material impregnado foi caracterizado por espectroscopia de absorção no infravermelho. A determinação da taxa de liberação do feromônio em laboratório, bem como o teste prático de captura de insetos em diferentes plantações, foram subseqüentemente realizados. Foram realizados testes com feromônios da Grapholita molesta (Lepidoptera: Tortricidae) e Leucoptera coffeella (Lepidoptera: Lyonetiidae), as principais pestes da maçã e café, respectivamente, em plantações brasileiras. Verificou-se que a taxa de liberação do feromônio depende do tipo de interação com as paredes dos poros do PVG. Os resultados indicaram uma boa performance do PVG, semelhante à de septos de borracha utilizados comercialmente como liberadores. Estes resultados, somados ao fato de que o PVG não é nocivo ao meio ambiente e pode ser reutilizado em vários ciclos de impregnação e liberação, fazem destes vidros porosos candidatos em potencial para aplicação no controle de pragas na agricultura.

This work demonstrates the viability and advantages of using porous silica glass as an insect pheromone dispenser, in order to control insect population in agriculture. Pieces of so-called Porous Vycor Glass (PVG) were impregnated with pheromones of different insects (both consisting of a single compound or a mixture of compounds). Studies were conducted to characterize the impregnated-PVG and to determine the pheromone release ratio under laboratory conditions. The practical application was verified in two different plantation areas, using the PVG impregnated with pheromone from Grapholita molesta (Lepidoptera: Tortricidae) and Leucoptera coffeella (Lepidoptera: Lyonetiidae), the main pests of apple and coffee plantations in Brazil, respectively. The release rate was dependent on the interaction between the molecules of the impregnated pheromone and the surface of the PVG pores. A good performance of the porous glass was observed, similar to that of rubber septa commercially used as pheromone dispensers.

Este estudo foi feito para determinar o padrão de produção de feromônio sexual em glândulas de fêmeas virgens de Leucoptera coffeella como uma medida indireta do comportamento de chamamento. O composto principal, 5,9-dimetilpentadecano (1) foi extraído de glândulas de feromônio de fêmeas virgens para ser usado em dois experimentos. No primeiro foi investigado o efeito do tempo na produção do feromônio (extratos de 10 fêmeas de dois dias de idade em intervalos de duas horas) e no outro foi avaliado o efeito da idade das fêmeas na produção de feromônio (10 fêmeas com idade entre 1 e 5 dias após a emergência). Os extratos hexânicos contendo 5 ng µL-1 de 5,9-dimetilheptadecano (2) como padrão interno foram analisados por CG. As fêmeas tiveram as maiores quantidades de feromônio nas últimas quatro horas da escotofase e nas duas primeiras horas da fotofase. Fêmeas de um dia de idade produziram as maiores quantidades de feromônio na glândula.

This study was undertaken to access the pattern of sex pheromone production in glands of virgin females of Leucoptera coffeella as an indirect measure of the calling behavior. The major compound, 5,9-dimethylpentadecane (1) was extracted from pheromone glands of virgin females to be used in two experiments. The first one investigated the effect of the pheromone production time by females (extracts of 10 females with age of two days were carried out at 2-hour intervals). The other experiment evaluated the effect of female age on pheromone production (10 females with age ranged from 1 to 5 days after emergence class were used). Hexane extracts were made with 5 ng µL-1 of 5,9-dimethylheptadecane (2) as internal standard and analyzed by GC. Females had the highest amount of pheromone at the last four hours in the dark and the two first hours in the light period. One-day old females produced the highest amount of pheromone in the glands.

Based on a specially created mass spectral database utilizing 23 tetradecenyl and 22 hexadecenyl acetate standards along with Kóvats retention indices obtained on a very polar stationary phase [poly (biscyanopropyl siloxane)] (SP 2340), (Z)-9-hexadecenyl acetate, (Z)-11-hexadecenyl acetate and (E)-8-hexadecenyl acetate were identified in active pheromone extracts of Elasmopalpus lignosellus. This identification was more efficient than our previous study using gas chromatography/mass spectrometry with a dimethyl disulfide derivative where we could only identify the first two acetates. The acetate composition of the pheromone gland differed from region to region in Brazil and from that from the Tifton (GA, USA) population, suggesting polymorphism or a different sub-species.

A mariposa marrom Thyrinteina arnobia (Stoll, 1872) (Lepidoptera: Geometridae) é uma praga importante em plantios de eucalipto no Brasil. Um indivíduo ginandromorfo de T. arnobia foi encontrado em uma população desta praga em criação de laboratório e descrito nesta nota.

The brown moth Thyrinteina arnobia (Stoll, 1872) (Lepidoptera: Geometridae) is an important pest in Brazilian eucalyptus plantations. A gynandromorph individual of T. arnobia was found in a population of this pest in a laboratory rearing and it is described.

Entre os heterópteros, o declínio da concentração de esperma pode ser um fator limitante para o sucesso reprodutivo desses insetos. Acasalamentos múltiplos conferem um reabastecimento de esperma e podem permitir um aumento do valor adaptativo das fêmeas. Neste estudo foi testada a hipótese de que a poliandria aumenta a viabilidade dos ovos. A longevidade de fêmeas de Podisus nigrispinus, bem como seus parâmetros reprodutivos em resposta a diferentes números de acasalamentos (0, 1, 2, 3 ou em coabitação com o mesmo macho) foi avaliada. Esse percevejo vem sendo usado em programas de controle biológico de pragas em reflorestamentos de Eucalipto no Brasil. Apesar da diminuição no tempo de sobrevivência das fêmeas, acasalamentos múltiplos mantiveram a viabilidade dos ovos e o período reprodutivo das fêmeas, permitindo um maior número de descendentes produzidos. Tais resultados indicam que um número mínimo de três acasalamentos antes da primeira postura permite uma maximização do sucesso reprodutivo dessa espécie.

The aim of this work was to test if egg viability of polyandrous females was increased with increasing number of matings. Longevity and reproductive output of females of the predatory stinkbug Podisus nigrispinus that were allowed to mate for 0, 1, 2, 3 times or were in the continuous presence of the same male was evaluated. Polyandry resulted in diminished sperm depletion. Females that had mated three times or that were in continuous presence of a male produced more offspring than females that mated once or twice throughout their lifetime. There was a negative correlation of mating history on female longevity. Results indicated that remating, either with same male or with different males were crucial for maximization of the reproductive success of females.

Entre insetos, o comportamento poliândrico é comum e tem significado importante no sucesso reprodutivo das fêmeas. Este trabalho objetivou estudar a freqüência de acasalamentos, em laboratório, da broca-da-graviola, Cerconota anonella Sepp, de forma a determinar se o comportamento poliândrico nessa espécie é comum. Cerca de 47% das fêmeas acasalaram mais de uma vez, porém houve diferenças no período das cópulas (precoce ou tardia). No geral fêmeas precoces foram mais freqüentes do que fêmeas tardias (P < 0.001, teste Binomial). Tais resultados sugerem que a poliandria em condições de campo pode ser possível em C. anonella.

Among insects polyandrous behavior is common and plays an important role in female reproductive output. The present study aimed to evaluate the mating frequency of the moth Cerconota anonella Sepp under laboratory conditions and to verify if polyandrous behavior is common in this species. Approximately 47% of females mated more than once. However they presented differences in the mating period (early or late). In general, precocious females were more frequent than late females (P < 0.001, Binomial test). Such results suggest that polyandry in C. anonella may be common in the field.

A atratividade de fêmeas de Euschistus heros (F.) (Hemiptera: Pentatomidae) aos oito estereoisômeros do 2,6,10-trimetiltridecanoato de metila, principal componente do feromônio sexual produzido pelos machos da espécie, foi estudada em olfatômetro de dupla escolha. Os bioensaios demonstraram que o estereoisômero (2R, 6R, 10S) foi necessário para a atratividade das fêmeas até a fonte de odor, destacando-se em relação aos outros. Apesar de exercer atratividade significativa para as fêmeas, a mistura de estereoisômeros quando comparada ao (2R, 6R, 10S) apresentou menor atratividade.

The attractiveness of Euschistus heros (F.) (Hemiptera: Pentatomidae) females to the eight stereoisomers of the methyl 2,6,10-trimethyltridecanoate, major component of the sex pheromone produced by the males of this species, was studied in a double choice olfactometer. Bioassays showed that the (2R, 6R, 10S) stereoisomer was necessary for the attractiveness of females, presenting better results in relation to the others. The stereoisomeric mixture was shown to present significative attractiveness to females, however, when compared to the (2R, 6R, 10S) stereoisomer, it showed lower attractiveness.

Propomos uma mudança na maneira tradicional de ensinar Entomologia na graduação e na pós-graduação. Para tanto, sugerimos um sistema no qual estudantes de graduação e pós-graduação interagem, discutindo Entomologia fora da sala de aula. Isto que os levaria a procurar conhecimento ativamente, ao invés de serem paternalisticamente "ensinados" sobre como devem aprender. Tal sistema não elimina aulas nem professores. Ao contrário, acreditamos que aulas e discussão extra-classe são complementares para um ensino efetivo. Nossos resultados mostram que estudantes de graduação e pósgraduação que interagem extra-classe obtêm melhores notas do que aqueles que não interagem, mesmo quando submetidos a provas elaboradas no estilo tradicional. Mais interessante ainda, evidências levam a crer que pós-graduandos envolvidos neste sistema conseguem empregos permanentes mais rápido do que os demais pós-graduandos. Aparentemente, a discussão extra-classe permite que o estudante pense livremente, ao invés de simplesmente acumular a informação passada durante as aulas. Fazendo isto, o estudante transforma informação em conhecimento e, por isso, é capaz de resolver até mesmo problemas com os quais nunca se deparou.

We propose a shift in the traditional way to teach Entomology for undergraduate and postgraduate courses. We envisage a system in which undergraduate and postgraduate students interact, discussing Entomology outside the classroom. This would get them to actively seek for knowledge, rather than being paternalistically told how they should learn. Such a system does not preclude lectures as a didactic strategy, nor it rules out lecturers as responsible for instructorship. On the contrary, we believe lectures and discussion outside classroom are complementary for effective teaching. Our results show that undergraduate and postgraduate students who interact outside classroom are able to get better grades even when submitted to traditional written tests. Moreover, it seems that postgraduate students who get involved in such a system get permanent jobs faster than those postgraduates not taking part in it. Apparently, the key here was that when discussing outside classroom, students are allowed to think freely, rather than simply accumulating information taught in classroom. In doing so, they transform information into knowledge, and therefore, are able to solve even unforeseen problems.