992 resultados para Lepidopteran pest


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First record of the alien pest Rhaponticum repens (Compositae) in the Iberian Peninsula.- Rhaponticum repens is reported for the first time for the flora of the Iberian Peninsula. The species is native from Central Asia and has become invasive in Argentina, Canada, Europe and the USA. It was detected for the first time in abandoned fields from Vilablareix, near the city of Girona (Catalonia, Spain) and in the valley of the Vinalopó in Alicante (Valencia, Spain), where it was collected as early as in 1959 but misdentified. Molecular data, based on nrDNA region ITS, suggest that the reported populations may be closely related to plants from the United States. Due to the extremely noxious character of the species and the possible relationship of Spanish plants with the invasive American populations, some kind of monitoring is recommended

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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.

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The identification and manipulation of chemical compounds involved in vital activities of arthropods have the potential for developing less aggressive pest control strategies. Herbivory induces the emission of volatile organic compounds involved in the recruitment of natural enemies, plant-plant interactions and repellency of other herbivores. In this report, we review the main chemical groups of volatile organic compounds and their ecological functions, provide an overview of the signal transduction pathways activated upon herbivory, and review the current state of knowledge for practical applications in pest management. We conclude by proposing perspectives for future research.

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Food production and preservation of the environment are among the challenges faced by contemporary society. In Brazil, as in most parts of the world, the possibility of increasing the agricultural area is limited by several factors. Thus, an increase in productivity through the application of innovative technologies is regarded as the best solution to overcome such a problem. For long, chemistry has contributed to agricultural innovations such as synthetic pesticides for pest management. However, due to the well-known adverse effects of these compounds, new "greener" strategies are being explored. Research in chemical ecology, in combination with other emerging sciences, is leading to the development of new technologies such as plant-based pesticides (biopesticides); synthetic pheromones and plant volatile organic compounds, both of them to manipulate insect behavior; chemical elicitors to boost plant resistance; and genetic engineering of plant varieties. In these, chemistry plays an important role in the identification and synthesis of functional compounds. These techniques may be incorporated in integrated pest management programs and may contribute to a sustainable agriculture in the future.

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Noctuids are phytophagous lepidopterans with some species causing significant damage to agriculture. The host plants, in turn, have developed defense mechanisms to cope with them, for instance chemical defenses. In this study we review the literature on plant volatiles induced by noctuids, and discuss the methodologies used to induce the production of volatiles that are usually employed in plant defense mechanisms. Future prospects involving this line of research in pest control are also discussed.

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Wood borer species of the families Euplatypodidae and Scolytidae were observed attacking trees of Pinus sp. in the Municipality of Ribas do Rio Pardo, state of Mato Grosso do Sul, Brazil, in March 2000. This plantation had been previously burned in an accidental fire in January 2000, causing the trees to become partially or totally unhealthy, rendering them more susceptible to attack of these pests. Galleries of these wood borers were opened with a chisel to observe parameters such as their direction and form of these galleries. Species observed as wood borers of Pinus sp. were Euplatypus parallelus, Euplatypus sp. (Coleoptera: Euplatypodidae) and Xyleborus affinis (Coleoptera: Scolytidae).

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In this thesis, I conduct a series of molecular systematic studies on the large phytophagous moth superfamily Noctuoidea (Insecta, Lepidoptera) to clarify deep divergences and evolutionary affinities of the group, based on material from every zoogeographic region of the globe. Noctuoidea are the most speciose radiations of butterflies and moths on earth, comprising about a quarter of all lepidopteran diversity. The general aim of these studies was to apply suitably conservative genetic markers (DNA sequences of mitochondrial—mtDNA—and nuclear gene— nDNA—regions) to reconstruct, as the initial step, a robust skeleton phylogenetic hypothesis for the superfamily, then build up robust phylogenetic frameworks for those circumscribed monophyletic entities (i.e., families), as well as clarifying the internal classification of monophyletic lineages (subfamilies and tribes), to develop an understanding of the major lineages at various taxonomic levels within the superfamily Noctuoidea, and their inter-relationships. The approaches applied included: i) stabilizing a robust family-level classification for the superfamily; ii) resolving the phylogeny of the most speciose radiation of Noctuoidea: the family Erebidae; iii) reconstruction of ancestral feeding behaviors and evolution of the vampire moths (Erebidae, Calpinae); iv) elucidating the evolutionary relationships within the family Nolidae and v) clarifying the basal lineages of Noctuidae sensu stricto. Thus, in this thesis I present a wellresolved molecular phylogenetic hypothesis for higher taxa of Noctuoidea consisting of six strongly supported families: Oenosandridae, Notodontidae, Euteliidae, Erebidae, Nolidae, and Noctuidae. The studies in my thesis highlight the importance of molecular data in systematic and phylogenetic studies, in particular DNA sequences of nuclear genes, and an extensive sampling strategy to include representatives of all known major lineages of entire world fauna of Noctuoidea from every biogeographic region. This is crucial, especially when the model organism is as species-rich, highly diverse, cosmopolitan and heterogeneous as the Noctuoidea, traits that represent obstacles to the use of morphology at this taxonomic level.

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The interference imposed the by weeds on corn decreases practically all vegetative characteristics. As consequence, the green ear and grain yield are also reduced. Losses due to the fall armyworm (Spodoptera frugiperda) attack can reduce corn grain yield up to 34%. In general, weed and insect control issues are addressed separately in research papers. Nevertheless, interaction between weeds and insects may exist. This study aimed to evaluate green ear and corn grain yield response to weed and fall armyworm control. A completely randomized block design with split-plots and five replicates was adopted. Corn cultivar AG 1051 was grown under weedy conditions or with control by hand hoeings performed at 20 and 40 days after planting. Fall armyworm control (applied to subplots) was performed with sprays of water (control), deltamethrin (5g active ingredient ha-1); neem oil, at 0.5% (diluted in water), and neem leaf extract at 5%. Each product was sprayed three times, at seven-day intervals, starting at the 7th day after planting, using 150 L ha-1 of the tank solution. Dry mass of the above-ground part, internode diameter, leaf length, leaf width, leaf area, green ear yield and grain yield of corn were reduced due to the lack of weed control. Fall armyworm control in the weeded plots did not influence green ear yield and grain yield, except green mass of marketable, husked ears, which was reduced when the caterpillar was not controlled. Without weed control, neem extracts and deltamethrin sprays provided highest yields of number and total weight of green ears with husks, number and weight of marketable ears with husks and number of marketable ears without husks. The best results for husked ear mass and for grain yield were obtained with neem extract and deltamethrin, respectively.

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Soil organisms play an important role in organic crops of Crotalaria juncea (Fabaceae) and are associated with the natural conservation of the environment. The present study was aimed to investigate the population of soil organisms in the organic culture of C. juncea, as well as its importance as a refuge for natural enemies. Dalbulus maidis (Hemiptera: Cicadellidae), Diabrotica sp. (Coleoptera: Chrysomelidae), Doru luteipes (Dermaptera: Forficulidae), Gryllus assimilis (Orthoptera: Gryllidae), Lagria villosa (Coleoptera: Lagriidae), Melanotus sp. (Coleoptera: Elateridae), Meloidogyne incognita (Tylenchida: Heteroderidae), Nephila clavipes (Araneae: Nephilidae), Orius insidiosus (Hemiptera: Anthocoridae), Pheidole sp. (Hymenoptera: Myrmicidae), Phyllophaga sp. (Coleoptera: Scarabeidae), Procornitermes sp. (Isoptera: Termitidae), Solenopsis sp. (Hymenoptera: Formicidae), and Utetheisa ornatrix (Lepidoptera: Arctiidae) were identified in C. juncea. The organisms that were found during a 3-month period in 144 trenches in C. juncea were pest species (84.47%) and natural enemies (15.53%) as well. Natural enemies had an average of 11.89 individuals per 1.08 m³ of soil cultivated with C. juncea. The abundance of organisms in the pod stage (5.49%) of C. juncea was lower than that in the vegetative (83.50%) and flowering (11.01%) stages. Crotalaria juncea plants can be used as part of a crop system for Integrated Pest Management.

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Chrysoperla externa (Neuroptera: Chrysopidae) larvae can avoid foraging on plants of Crotalaria juncea (Fabaceae) after the issuance of floral buds, when the prey of Utetheisa ornatrix (Lepidoptera: Arctiidae) incorporate toxic pyrrolizidine alkaloids from this plant. This reduces the predation and favors increasing the number of adults and eggs of this defoliator on crops of this plant. The aim of the present paper was to evaluate some biological and ecological aspects of C. externa and U. ornatrix on the organic crop of C. juncea in the EMBRAPA Maize and Sorghum in Sete Lagoas, Minas Gerais State, Brazil. Chrysoperla externa and U. ornatrix were more abundant in the vegetative and flowering stages of C. juncea, respectively, with caterpillars of this defoliator feeding on leaves and seeds of this plant. The duration of the stages/instars, survival, lifetime fecundity, and oviposition showed that the branches of C. juncea are a suitable food for U. ornatrix. The abundance of adults and larvae of C. externa was lower in the flowering and pods stages of C. juncea, respectively, when the postures of U. ornatrix are present, probably due to the toxicity of the eggs of this prey to this predator. During these stages, C. externa may be reared with alternative hosts, and when the crops of C. juncea are scarce, an artificial diet should be used for rearing this defoliator in the laboratory for biological research and the development of biological control tactics.

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Enabling Change in Universities: Enhancing Education for Sustainable Development with Tools for Quality Assurance This thesis deals with enabling change in universities, more explicitly enhancing education for sustainable development with tools for quality assurance. Change management is a discipline within management that was developed in the 1980s because business changed from being predictable to unpredictable. The PEST mnemonic is a method to categorize factors enabling change; such as political, economic, socio-cultural and technological factors, which all affect higher education. A classification of a change, in either hard or soft, can help understanding the type of change that an organization is facing. Hard changes are more applied to problems that have clear objectives and indicators, with a known cause of the problem. Soft changes are applied to larger problems that affect the entire organization or beyond it. The basic definition for sustainable development is: the future generations should have similar opportunities as the previous. The UN has set as a global goal an integration of education for sustainable development (ESD) at all levels of education during 2005- 2014. The goal is set also in universities, the graduates of which are future leaders for all labor markets. The objective for ESD in higher education is that graduates obtain the competence to take economic, social and environmental costs and benefits into account when making decisions. Knowledge outcomes should aim for systematic and holistic thinking, which requires cross disciplinary education. So far, the development of ESD has not achieved its goals. The UN has identified a need for more transdisclipnary research in ESD. A joint global requirement for universities is quality assurance, the aim of which is to secure and improve teaching and learning. Quality, environmental and integrated management systems are used by some universities for filling the quality assurance requirements. The goal of this thesis is to open up new ways for enhancing ESD in universities, beyond the forerunners; by exploring how management systems could be used as tools for promoting ESD. The thesis is based on five studies. In the first study, I focus on if and how tools for quality assurance could be benefitted for promoting ESD. It is written from a new perspective, the memetic, for reaching a diversity of faculty. A meme is an idea that diffuses from brain to brain. It can be applied for cultural evolution. It is a theory that is based on the evolutionary theory by Darwin, applied for social sciences. In the second Paper, I present the results from the development of the pilot process model for enhancing ESD with management systems. The development of the model is based on a study that includes earlier studies, a survey in academia and an analysis of the practice in 11 universities in the Nordic countries. In the third study, I explore if the change depends on national culture or if it is global. It is a comparative study on both policy and implementation level, between the Nordic countries and China. The fourth study is a single case study based on change management. In this study, I identify what to consider in order to enable the change: enhancing ESD with tools for quality assurance in universities. In the fifth Paper, I present the results of the process model for enhancing ESD with management systems. The model was compared with identified drivers and barriers for enhancing ESD and for implementing management systems. Finally, the process model was piloted and applied for identifying sustainability aspects in curricula. Action research was chosen as methodology because there are not already implemented approaches using quality management for promoting ESD, why the only way to study this is to make it happen. Another reason for choosing action research is since it is essential to involve students and faculty for enhancing ESD. Action based research consists of the following phases: a) diagnosing, b) planning action, c) taking action and d) evaluating action. This research was made possible by a project called Education for Sustainable Development in Academia in the Nordic countries, ESDAN, in which activities were divided into these four phases. Each phase ended with an open seminar, where the results of the study were presented. The objective for the research project was to develop a process for including knowledge in sustainable development in curricula, which could be used in the quality assurance work. Eleven universities from the Nordic countries cooperated in the project. The aim was, by applying the process, to identify and publish examples of relevant sustainability aspects in different degree programs in universities in the Nordic countries. The project was partly financed by the Nordic Council of Ministers and partly by the participating pilot universities. Based on the results of my studies, I consider that quality, environmental and integrated management systems can be used for promoting ESD in universities. Relevant sustainability aspects have been identified in different fields of studies by applying the final process model. The final process model was compared with drivers and barriers for enhancing ESD and for implementing management systems in universities and with succeeding with management systems in industry. It corresponds with these, meaning that drivers are taken into account and barriers tackled. Both ESD and management systems in universities could be considered successful memes, which can reflect an effective way of communication among individuals. I have identified that management systems could be used as tools for hard changes and to support the soft change of enhancing ESD in universities with management system. Based on the change management study I have summarized recommendations on what to consider in order to enable the studied change. The main practical implications of the results are that the process model could be applied for assessment, benchmarking and communication of ESD, connected to quality assurance, when applied. This is possible because the information can be assembled in one picture, which facilitates comparison. The memetic approach can be applied for structuring. It is viable to make comparative studies between cultures, for getting insight in special characteristics of the own culture. Action based research is suitable for involving faculty. Change management can be applied for planning a change, which both enhancing ESD and developing management systems are identified to be.

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Herbicides and plant growth regulators are often used in sugarcane management. However, the use of non-selective pesticides can cause adverse effects on the efficiency of beneficial insects in integrated pest management. Within this context, this study aimed to evaluate the effect of such products on the immature stages of the parasitoid Trichogramma galloi. Eggs of Diatraea saccharalis containing the parasitoid at the egg-larva stage and at the prepupal and pupal stages were immersed in test solutions of the following pesticides (maximum recommended doses for sugarcane): herbicides clomazone and diuron + hexazinone, and plant growth regulators trinexapac-ethyl and sulfometuron-methyl. The biological properties evaluated were emergence (F1 and F2) and number of eggs parasitized by T. galloi (F1). The products were classified according to percentage of reduction in emergence and parasitism: harmless (<30%), slightly harmful (30-79%), moderately harmful (80-99%) and harmful (>99%). The pesticides evaluated were considered to be harmless or slightly harmful to immature T. galloi and, thus, their use should be preferred for preserving this parasitoid species in sugarcane management programs.