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Naupactus cervinus is a parthenogenetic weevil native to South America that is currently distributed worldwide. This flightless species is polyphagous and capable of modifying gene expression regimes for responding to stressful situations. Naupactus cervinus was first reported in the continental United States in 1879 and has rapidly colonized most of the world since. Previous studies suggested that an invader genotype successfully established even in areas of unsuitable environmental conditions. In the present work, we analyze mitochondrial and nuclear sequences from 71 individuals collected in 13 localities across three states in the southern US, in order to describe the genetic diversity in this area of introduction that has not yet been previously studied. Our results suggest that 97% of the samples carry the most prevalent invader genotype already reported, while the rest shows a close mitochondrial derivative. This would support the hypothesis of a general purpose genotype, with parthenogenesis and its associated lack of recombination maintaining the linkage of genetic variants capable of coping with adverse conditions and enlarging its geographical range. However, demographic advantages related to parthenogenetic reproduction as the main driver of geographic expansion (such as the foundation of a population with a single virgin female) cannot be ruled out. Given the historical introduction records and the prevalence of the invader genotype, it is possible that the continental US may act as a secondary source of introductions to other areas. We propose that both the parthenogenesis and scarce genetic variation in places of introduction may, in fact, be an asset that allows N. cervinus to thrive across a range of environmental conditions.

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BACKGROUND: The invasion of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) into the New World has made it possible for this pest to hybridize with a native American species, H. zea (Boddie), under natural conditions. We investigated the viability and development of hybrids of these two Helicoverpa species. We reared the parental species and evaluated crosses between H. armigera males and H. zea females and vice versa, two intercrosses between hybrids, and eight backcrosses between hybrids and parental species. We estimated the length of immature stages, fecundity, survival, sex ratio, and heterosis. RESULTS: Although hybridization occcurred, with heterosis during the development of immatures, reproductive incompatibilities also were observed between the parental species and between hybrids from subsequent crosses. The interspecific crosses between hybrids and backcrosses confirmed the possibility of introgression events and their perpetuation in field populations. The results indicate that hybridization events are favored at high population levels, while at low population levels the 'species identities' will be maintained. CONCLUSIONS: The possibility of interspecific gene flow and its perpetuation through successive crosses and backcrosses suggests several recommenations for management. Populations of both species should be maintained at an equilibrium level to reduce the chance of interspecific crosses, which are presumably more likely to occur during pest outbreaks. The existence of hybridization and resistance to different active pesticide ingredients should be monitored. All practices related to managing the resistance of these pests to chemical and biological insecticides should be systematized to reduce the chance of selecting for resistant individuals.

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There is much information regarding the association of Psocoptera and coffee as stored grain pests and little is known about their presence in coffee plants. We conducted a survey in a coffee plantation of Coffea canephora in the municipality of Candeias do Jamari, Rondônia state, Brazil, where we obtained the first record of a coffee plant as a host of Psocoptera in the Brazilian Amazon region, and the first record of a representative of the family Archipsocidae (Archipsocus lenkoi) for the state of Rondônia. The psocid population was concentrated and not evenly distributed over the survey area, which indicates an irregular distribution pattern. We have not detected damage or injury to the coffee plants and therefore we cannot consider these psocids as a pest in the coffee plantation.(AU)

Há muita informação sobre a associação de Psocoptera e café como peste em grãos armazenados, mas pouco se sabe sobre sua presença nas plantas do café. Nós realizamos uma amostragem em uma plantação de café de Coffea canephora no município de Candeias do Jamari, Rondônia, onde obtivemos o primeiro registro de uma planta de café como hospedeira de Psocoptera na Amazônia brasileira e o primeiro registro de um representante da família Archipsocidae (Archipsocus lenkoi) para o estado de Rondônia. A população de psocídeos estava concentrada e não distribuída uniformemente na área de amostragem, o que indica um padrão de distribuição irregular. Não detectamos danos ou injúrias nas plantas de café e, portanto, não podemos considerar esses psocídeos como uma praga na plantação de café.(AU)

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The development, survival, and reproduction of ectothermic organisms such as insects are strongly influenced by temperature. Because insects respond to temperature by accelerating or reducing their development rate, population growth is directly associated with temperature variations. Here, daily minimum and maximum temperatures and degree-day model approaches were used to estimate the number generation per year (voltinism) of Mythimna sequax Franclemont, Neoleucinodes elegantalis (Guenée), Spodoptera cosmioides (Walker), and Spodoptera eridania (Cramer) over a 34-year period in southern Brazil. Additionally, we assessed the effects of El Niño Southern Oscillation (ENSO) events on voltinism. While an increased number of generations were estimated in warmer regions, comprising mainly northwestern Paraná, fewer generations were estimated in the colder regions of Santa Catarina and Rio Grande do Sul. For all species, the location was the factor that explained most of the variation observed in voltinism (average of 76.9%). Inter-annual changes in voltinism also varied depending on location, and differences of up to five generations among years were obtained in colder regions. On the other hand, ENSO events had a minor influence on the species voltinism. Our findings provide an important contribution to the understanding of spatio-temporal variations in voltinism of insects, and how temperature changes may increase their population growth.

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Abstract The current study has investigated whether arthropod richness in soybean monoculture (Glycine max) decreases, whereas the abundance, mainly of herbivores, increases as distance from Parque Nacional do Iguaçu (PNI) increases. Active and passive arthropod collections were performed at different distances (5, 50, 300 and 600 m) from PNI. Arthropod richness in agricultural area decreased as distance from PNI increased. Results have shown that Conservation Units can act as source of ecosystem services for surrounding monocultures. The presence of pollinators in collections has confirmed the important role played by protected natural areas in agriculture, since they contribute to this economic activity by providing ecosystem services such as pollination.

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ABSTRACT The owlet moths (Lepidoptera: Noctuidae) Anicla infecta (Ochsenheimer 1816), Elaphria agrotina (Guenée 1852) and Spodoptera frugiperda (J.E. Smith 1797) occur in the entire American continent. These polyphagous moths have a preference for grasses, and have different biological habits. In this study, the populations of these three species were evaluated monthly with light traps in the Brazilian Savannah, ranging a span of four crop seasons (from July, 2013 to June, 2017). The population data were analyzed and correlated with the meteorological variables: maximum temperature, minimum temperature, relative humidity and precipitation. A total of 4719 individuals were collected in the following percentages: A. infecta (n = 459; 9.73%), E. agrotina (n = 1809; 38.33%) and S. frugiperda (n = 2451; (51.94%). The abundance of all species went down from the first crop season (2013/2014) to the third (2015/2016). In the fourth crop season (2016/2017), the populations of A. infecta and E. agrotina stabilized, but the abundance of S. frugiperda experienced further decrease. The numbers of individuals of three species declined when precipitation was much above (crop season 2014/2015) and below (crop season 2015/2016) than expected by the climatological normal. There were significant, but different degrees of correlation, between the meteorological factors and the ONI index (Oceanic Niño Index - indicator for monitoring El Niño-Southern Oscillation or "ENSO") with respect to monthly population variations. The results are discussed in accordance with principles of the Integrated Pest Management (IPM) in mind, given the continental distribution and agricultural importance of the three owlet moth species studied.

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Climate induced species range shifts might create novel interactions among species that may outweigh direct climatic effects. In an agricultural context, climate change might alter the intensity of competition or facilitation interactions among pests with, potentially, negative consequences on the levels of damage to crop. This could threaten the productivity of agricultural systems and have negative impacts on food security, but has yet been poorly considered in studies. In this contribution, we constructed and evaluated process-based species distribution models for three invasive potato pests in the Tropical Andean Region. These three species have been found to co-occur and interact within the same potato tuber, causing different levels of damage to crop. Our models allowed us to predict the current and future distribution of the species and therefore, to assess how damage to crop might change in the future due to novel interactions. In general, our study revealed the main challenges related to distribution modeling of invasive pests in highly heterogeneous regions. It yielded different results for the three species, both in terms of accuracy and distribution, with one species surviving best at lower altitudes and the other two performing better at higher altitudes. As to future distributions our results suggested that the three species will show different responses to climate change, with one of them expanding to higher altitudes, another contracting its range and the other shifting its distribution to higher altitudes. These changes will result in novel areas of co-occurrence and hence, interactions of the pests, which will cause different levels of damage to crop. Combining population dynamics and species distribution models that incorporate interspecific trade-off relationships in different environments revealed a powerful approach to provide predictions about the response of an assemblage of interacting species to future environmental changes and their impact on process rates.

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O conhecimento da dinâmica populacional e da distribuição espacial de insetos pragas em culturas hospedeiras é fundamental para a determinação de medidas adequadas de controle. Diabrotica speciosa Germar, 1824 é uma praga polifaga que reduz a produtividade do tabaco, através do consumo da área foliar na alimentação. Objetivou-se com este estudo analisar a flutuação populacional e a distribuição espacial de Diabrotica speciosa (Coleoptera: Chrysomelidae) na cultura do tabaco, avaliando o impacto da vegetação adjacente á lavoura. A pesquisa foi conduzida em uma lavoura de tabaco orgânico no município de Santa Cruz doSul, Rio Grande do Sul, durante a safra de 2009/2010, utilizando-se de armadilhasde Malaise. Foi coletado um total de 3 217 indivíduos adultos de Diabroticaspeciosa, com 85,8% dos espécimes amostrados nos meses de dezembro e janeiroe com a maior abundância no interior do cultivo, sendo a disponibilidade defolhas de tabaco para a alimentação o parâmetro mais determinante na ocorrênciada espécie no plantio.

Knowledge of population dynamics and spatial distribution of insect pests Knowledge of population dynamics and spatial distribution of insect pests on host crops is essential to determine of appropriate control measures. Diabrotica speciosa Germar, 1824 is a polyphagous pest that reduces the productivity of tobacco, through consumption of leaf area in the feed. The objective of this study was to analyze the population fluctuation and spatial distribution of Diabrotica speciosa (Coleoptera: Chrysomelidae) in tobacco growing, evaluating the impact of vegetation adjacent to plantation. The research was conducted in an organic crop of tobacco in Santa Cruz do Sul, Rio Grande do Sul, Brazil, during the growing season of 2009/2010, using Malaise traps. We collected a total of 3,217 adults of Diabrotica speciosa, with 85.8% of specimens sampled in the months of December and January and with the highest abundance in the interior of the culture, and the availability of tobacco leaves to feed the most crucial parameter in the occurrence of the species in planting.

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Quando o café constituía a principal riqueza brasileira e São Paulo detinha a liderança absoluta na sua produção e comércio, uma praga veio colocar sob ameaça toda aquela pujança econômica. Conhecida como broca-do-café, era causada por um minúsculo inseto aparecido em fazendas de Campinas. De lá partiu a notificação ao governo paulista, em maio de 1924. A gravidade da situação levou o governo estadual a compor uma comissão científica chefiada por Arthur Neiva, responsável por levar a cabo o plano de combate. A campanha contra a broca combinou a implementação de um vigoroso aparato de pesquisa e fiscalização com amplo trabalho de divulgação científica, que lançou mão de estratégias vanguardistas de difusão, como o cinema. Em fins de 1927, a Comissão foi formalmente extinta após a criação de uma instituição permanente de pesquisa agrícola: o Instituto Biológico de Defesa Agrícola e Animal.

When coffee was Brazil's chief source of wealth and São Paulo was the absolute leader in its production and trade, a plague suddenly came to threaten this mighty economic asset. The cause was a tiny insect called the coffee borer, which began showing up on plantations in the Campinas area. The São Paulo state government learned of the pest in May 1924 via news from Campinas. The situation was so serious that the state government formed a scientific commission, headed by Arthur Neiva, who was to lead the battle against the borer. The ensuing campaign put in place a sound system of research and surveillance, complemented by broad-reaching scientific education that relied on such vanguard tools as cinema. In late 1927, the Commission was officially dissolved, following creation of a permanent agricultural research center: the Instituto Biológico de Defesa Agrícola e Animal (Biological Institute for Agricultural and Animal Defense).

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