549 resultados para Larva minadora


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Helcystogramma sp., es una nueva especie de microlepidóptero que afecta desde la siembra hasta la cosecha del boniato o camote (Ipomoea batatas L. Lam.) en Cuba. Debido a la falta de conocimientos y a la escasa bibliografía relacionada con las especies del género Helcystogramma en nuestro país, nos propusimos como objetivo conocer aspectos bio-ecológicos de este microlepidóptero, con la finalidad de proporcionar nuevos conocimientos para un futuro manejo de esta plaga. El trabajo se realizó desde septiembre 2013 a septiembre de 2014, en el Instituto de Investigaciones de Viandas Tropicales (INIVIT), Santo Domingo, Villa Clara, Cuba. Los insectos se estudiaron por observación directa en campos de I. batatas. La larva de este microlepidóptero es muy ágil, dobla la hoja, la cual pega con hilos de seda, creando una protección para su desarrollo hasta el estado de pupa, se alimenta dentro de esta cavidad a partir de la misma hoja, sin afectar la epidermis inferior. Sus poblaciones han aumentado considerablemente, llegando a 20 larvas/m2 en verano. La especies Helcystogramma sp., se cita por primera vez para Cuba y además se registra como una nueva especie de insecto que se alimenta del boniato. ABSTRACT. Primer registro de Helcystogramma sp. (Lepidoptera: Gelechiidae) en Cuba. Helcystogramma sp. is a new species of microlepidoptera affecting from planting to sweet potato (I. batatas L. Lam.) harvest crop in Cuba. Due to the lack of knowledgze and limited literature relate with the Helcystogramma genus in our country, the goal of this study was to know the bioecological aspects of such microlepidoptera, in order to provide new insights for future management of this pest. The study was conducted from September 2013 to September 2014 at the Research Institute of Tropical Root and Tuber Crops, Bananas and Plantains (INIVIT), Santo Domingo, Villa Clara, Cuba. Insects were studied by direct observation in sweet potato (I. batatas) fields. The microlepidoptera larvae is very agile, folds the sheet which sticks with silk threads, creating a protection for its development to the pupal stage. The larvae will feed in the cavity from the same leaf without affecting the lower epidermis. Their populations have increased significantly, reaching 20 larvae / m2 in summer. The species Helcystogramma sp., is cited for the first time in Cuba and it is reported as a new species of insect that feeds on sweet potato leaves.

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Boloceroides spp. are looking like an untidy mop, this anemone is sometimes seen in sea grass areas on many of our shores. It is possibly seasonal. Sometimes, large numbers are seen (up to 10-20 animals in a trip) and then none at all.  Tiny swimming anemones may sometimes be confused with Sea grass anemones which have translucent tentacles with tiny spots. The swimming anemone harbors symbiotic single-celled algae (zooxanthellae). The algae undergo photosynthesis to produce food from sunlight. The food produced is shared with the sea anemone, which in return provides the algae with shelter and minerals. The oral disk and tentacle muscles are used to obtain, retain, and ingest prey; in Boloceroides spp. tentacles can autotomize if it is needed to evade a predator. Tentacles can control body form by use of their endodermal muscles. Retractors are longitudinal muscles that will aid in withdrawing tentacles and the oral disk if they are exposed to the open air.  This hypothesis is furthered because in comparison to other sea anemones, Boloceroides is loosely attached to its respective substrate, thus allowing the pedal disk to detach quickly resulting in a rapid swimming response. Boloceroides can reproduce both sexually and asexually. As Anthozoans, Boloceroides produce sexually by bypassing the medusa life cycle stage; this allows Boloceroides (and all Anthozoans) to release their egg and sperm creating planula a bilaterally symmetrical, flattened, ciliated, motile larva.

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Pempheris vanicolensis has reported for the first time from Persian Gulf (Kish Island). Various aspects of the biology of P. vanicolensis Cuvier & Valenciennes, a recent Lessepsian (Suez Canal) immigrant into the Mediterranean, are given. Red Sea and Mediterranean populations were compared, and the results indicate that the spawning season is shortened in the Mediterranean, continuing from April to September, as opposed to year-round in the Red Sea. Descriptions of a ripe ovary and post-larva from the Mediterranean are given. Individuals reach a mean size of 10.8 cm in their first year, and 14.4 cm in the second year. Little change has occurred in the diet of the immigrant population, and both populations feed nocturnally, chiefly on larval and adult stages of planktonic crustaceans. Direct underwater observations on the diurnal behavior of the species show that the fish leave their daytime cave shelter at sunset, congregate at a nearby site and then migrate inshore and disperse into small groups to feed. Before dawn, they reassemble at the cave's entrance, and finally enter it at sunrise, after the school has built up. Observations on Persian Gulf sweepers show that the fish are segregated into size groups, ranging 15–18 cm adults at depths of 3 m.

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The primary goal of systems biology is to integrate complex omics data, and data obtained from traditional experimental studies in order to provide a holistic understanding of organismal function. One way of achieving this aim is to generate genome-scale metabolic models (GEMs), which contain information on all metabolites, enzyme-coding genes, and biochemical reactions in a biological system. Drosophila melanogaster GEM has not been reconstructed to date. Constraint-free genome-wide metabolic model of the fruit fly has been reconstructed in our lab, identifying gaps, where no enzyme was identified and metabolites were either only produced or consume. The main focus of the work presented in this thesis was to develop a pipeline for efficient gap filling using metabolomics approaches combined with standard reverse genetics methods, using 5-hydroxyisourate hydrolase (5-HIUH) as an example. 5-HIUH plays a role in urate degradation pathway. Inability to degrade urate can lead to inborn errors of metabolism (IEMs) in humans, including hyperuricemia. Based on sequence analysis Drosophila CG30016 gene was hypothesised to encode 5- HIUH. CG30016 knockout flies were examined to identify Malpighian tubules phenotype, and shortened lifespan might reflect kidney disorders in hyperuricemia in humans. Moreover, LC-MS analysis of mutant tubules revealed that CG30016 is involved in purine metabolism, and specifically urate degradation pathway. However, the exact role of the gene has not been identified, and the complete method for gap filling has not been developed. Nevertheless, thanks to the work presented here, we are a step closer towards the development of a gap-filling pipeline in Drosophila melanogaster GEM. Importantly, the areas that require further optimisation were identified and are the focus of future research. Moreover, LC-MS analysis confirmed that tubules rather than the whole fly were more suitable for metabolomics analysis of purine metabolism. Previously, Dow/Davies lab has generated the most complete tissue-specific transcriptomic atlas for Drosophila – FlyAtlas.org, which provides data on gene expression across multiple tissues of adult fly and larva. FlyAtlas revealed that transcripts of many genes are enriched in specific Drosophila tissues, and that it is possible to deduce the functions of individual tissues within the fly. Based on FlyAtlas data, it has become clear that the fly (like other metazoan species) must be considered as a set of tissues, each 2 with its own distinct transcriptional and functional profile. Moreover, it revealed that for about 30% of the genome, reverse genetic methods (i.e. mutation in an unknown gene followed by observation of phenotype) are only useful if specific tissues are investigated. Based on the FlyAtlas findings, we aimed to build a primary tissue-specific metabolome of the fruit fly, in order to establish whether different Drosophila tissues have different metabolomes and if they correspond to tissue-specific transcriptome of the fruit fly (FlyAtlas.org). Different fly tissues have been dissected and their metabolome elucidated using LC-MS. The results confirmed that tissue metabolomes differ significantly from each other and from the whole fly, and that some of these differences can be correlated to the tissue function. The results illustrate the need to study individual tissues as well as the whole organism. It is clear that some metabolites that play an important role in a given tissue might not be detected in the whole fly sample because their abundance is much lower in comparison to other metabolites present in all tissues, which prevent the detection of the tissue-specific compound.

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The state of Rio Grande do Norte counts with a relevant potential in the shrimp farming supply chain. In the larviculture step the state responds for more than half of the national production. In the farming step it is the second largest producer. In the industrial step, its industries have almost 40% of the shrimp processing capacity of the northeast of Brazil. However, this country has the highest tax rate comparing with the main shrimp producer countries. Considering the influence of taxes in the competition among companies, the main goal of this research is to analyze the impact of indirect taxes in the above steps of the supply chain. To achieve it, it will be used the data of the 2011 Census of the Shrimp Farming and it will be applied the Herfindahl-Hirschman Index to identify the market form of those steps. In order to contribute with the characterization of the supply chain, CEO´s of farms and industries will be interviewed. The price-elasticity of the shrimp larvae, the in natura shrimp and the processed shrimp will be analyzed in order to verify the possibility that each one of those three steps has to pass-through the onus of the end of benefit over the ICMS. The data analysis shows that the larviculture step functions as a duopoly and, facing the end of that benefit, it will be able to pass-through most its onus to the farming step. On the other hand, this step functions similar to a perfect competing market, which diminishes its capacity to pass-through that onus to the processing step. This step operates as oligopoly with a lower concentration than the larviculture step but, due to the fact that it faces an oligopsony, it will end up assuming most of that onus, which will cause a decrease in the amount of processed shrimp. It is concluded that the end of that benefit would impact negatively, in this state, the supply chain at all, but mainly the farming and the industrial steps

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Alguns aspectos biologicos de Tetranychus evansi Baker & Pritchard foram estudados em laboratorio, incluindo a duracao das formas jovens e a capacidade reprodutiva, em plantas de tomate var. Rossol. As duracoes dos estagios do ovo, larva, protoninfa e deutoninfa foram de 4,8; 2,6, 2,4 e 3,2 dias, respectivamente, correspondendo a uma duracao total de, aproximadamente treze dias de ovo a adulto, para ambos os secos. Os niveis mais altos de oviposicao foram obtidos do quarto ao decimo ia, aproximadamente. Uma media de 105,7 ovos foram postos durante todo o periodo de oviposicao. Provavelmente, a utilizacao de folhas medianas ou basais, ao inves de apicais, como substrato teria resultado em um ciclo biologico mais curto e em uma oviposicao total maior do que os obtidos neste estudo.

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Background Flatfish metamorphosis denotes the extraordinary transformation of a symmetric pelagic larva into an asymmetric benthic juvenile. Metamorphosis in vertebrates is driven by thyroid hormones (THs), but how they orchestrate the cellular, morphological and functional modifications associated with maturation to juvenile/adult states in flatfish is an enigma. Since THs act via thyroid receptors that are ligand activated transcription factors, we hypothesized that the maturation of tissues during metamorphosis should be preceded by significant modifications in the transcriptome. Targeting the unique metamorphosis of flatfish and taking advantage of the large size of Atlantic halibut (Hippoglossus hippoglossus) larvae, we determined the molecular basis of TH action using RNA sequencing. Results De novo assembly of sequences for larval head, skin and gastrointestinal tract (GI-tract) yielded 90,676, 65,530 and 38,426 contigs, respectively. More than 57 % of the assembled sequences were successfully annotated using a multi-step Blast approach. A unique set of biological processes and candidate genes were identified specifically associated with changes in morphology and function of the head, skin and GI-tract. Transcriptome dynamics during metamorphosis were mapped with SOLiD sequencing of whole larvae and revealed greater than 8,000 differentially expressed (DE) genes significantly (p < 0.05) up- or down-regulated in comparison with the juvenile stage. Candidate transcripts quantified by SOLiD and qPCR analysis were significantly (r = 0.843; p < 0.05) correlated. The majority (98 %) of DE genes during metamorphosis were not TH-responsive. TH-responsive transcripts clustered into 6 groups based on their expression pattern during metamorphosis and the majority of the 145 DE TH-responsive genes were down-regulated. Conclusions A transcriptome resource has been generated for metamorphosing Atlantic halibut and over 8,000 DE transcripts per stage were identified. Unique sets of biological processes and candidate genes were associated with changes in the head, skin and GI-tract during metamorphosis. A small proportion of DE transcripts were TH-responsive, suggesting that they trigger gene networks, signalling cascades and transcription factors, leading to the overt changes in tissue occurring during metamorphosis.

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Dissertação de mest. em Estudos Marinhos e Costeiros, especialização em Aquacultura, Unidade de Ciências e Tecnologias dos Recursos Aquáticos, Univ. do Algarve, 1994

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Estudou-se a resistência de 50 variedades de Vigna unguiculataWalp ao ataque de Liriomyza sativae Blanchard, sob condições de irrigação por sulco. As variedades que sofreram os menores e os maiores danos causados pelo inseto foram: VITA-3 e 5F-PI-112, respectivamente, observando-se susceptibilidades intermediárias das variedades estudadas entre estes dois extremos.

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Ten species of Copestylum (Diptera: Syrphidae) were reared from fruits and flowers in Costa Rica, Ecuador and Trinidad. Seven were new and in this paper, we describe them, their development sites and the third stage larva and/or the puparium of all ten species. One new synonym is proposed, Copestylum pinkusi (Curran) [= Copestylum cinctiventre (Curran)]. Similarities and differences between these new and other Copestylum species, suggest they separate into two groups, referred to as the Vagum and Cinctiventre species groups. Features characterising these groups for both adult and early stages are assessed. Each species was also distinguished using adult and early stage characters. Within the Vagum group, adults were more disparate morphologically than the larval stage; this was reversed in the Cinctiventre group. Adult colour patterns are probably cryptic in function and for disguise. Vagum species have disruptive marks, while the Cinctiventre species have reflective colours. Biologically, the groups are almost distinguished by larval development sites. Vagum species use predominantly fruits and have a larval stage that is relatively generalised in form and habit. Cinctiventre species are confined to developing in flowers and the larva is more specialised. A key to both adult and early stages of all ten species is provided.

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As células do corpo gorduroso de Pachycondyla (=Neoponera) villosa distribuem-se como uma única camada entre a cutícula e o trato digestivo, formando um conjunto de células agrupadas e recobertas por uma fina membrana. Não foram identificados tipos celulares distintos por meio da ultramorfologia, porém a histologia revelou três tipos celulares distintos: os trofócitos, mais abundantes, as células de urato, distribuídas por entre os trofócitos, e os enócitos, menos abundantes que os demais. Os enócitos são comumente observados próximos da cutícula. Histoquimicamente, os trofócitos apresentaram reação positiva para proteínas básicas no núcleo e no citoplasma e reação fortemente positiva nos grânulos citoplasmáticos. O teste para carboidratos foi fortemente positivo em todo o citoplasma, enquanto para os lipídeos observou-se reação positiva nas vesículas citoplasmáticas. em relação às células de urato, estas apresentaram reação positiva para proteínas básicas no núcleo e citoplasma, por entre as vesículas. Essas células não apresentaram reação para o teste de PAS e Sudan Black B. Quanto aos enócitos, estes apresentaram citoplasma fracamente positivo ao PAS e fortemente positivo ao Sudan Black B e para o azul de bromofenol.

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This work investigates the acceptance of different food types and sizes by Macrobrachium rosenbergii during each larval stage. Food intake of dry and wet formulated diets of four different size classes (250-425, 425-710, 710-1000 and 1000-1190 mum), as well as Artemia nauplii, was determined. Larvae of each zoeal stage were stocked in beakers and fed ad libitum. After 30-45 min, the digestive tract of each larva was observed under a stereomicroscope. Acceptance was evaluated by food intake frequency (FFI). There was no significant interaction (P<0.05) between inert diet size and FFI for each larval stage. Therefore, food intake during larval development is independent of food particle size. The ingestion of Artemia nauplii, was significantly higher by larvae between stages II and VI. Between stages VII and XI, FFI for Artemia nauplii and wet diet was similar, while the FFI of the dry diet was similar to live food between stages IX and XI. The wet diet was ingested by more than 50% of the larvae only from stage VII onwards, while the dry diet from stage VIII onwards. These results indicate that larvae could be fed Artemia nauplii only until stage VI. Diet supplementation should start from stage VII onwards, using food particles varying from 250 to 1190 mum. (C) 2003 Elsevier B.V. B.V. All rights reserved.

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The functional response between ingestion rate and food concentration was determined for each larval stage of Macrobrachium rosenbergii. Artemia franciscana nauplii were supplied at 2,4, 6, 8, 10 and 12 per milliliter. The nauplii were counted by sight using a Pasteur pipette and transferred to Petri dishes containing 40 ml of brackish water (12 parts per thousand) lying on the top of black plastic. One larva at each stage was individually placed into each Petri dish containing different food density. After 24 h, each larva was removed from the Petri dish and the leftover nauplii were counted. The amount consumed was determined by the difference between the initial and final number of nauplii. Ingestion rate (I) increased as food density (P) increased and was defined by the model I=I-m(1-e(-kP)). The results suggest four levels of ingestion during larval development. The first level includes stages II, III and IV, with average maximum consumption of about 40 nauplii/day; the second level includes stages V and VI, with consumption of approximately 55 nauplii/day; the third level includes stages VII and VIII, with consumption of 80-100 nauplii/day. The fourth level includes stages IX, X and XI, in which the high values for maximum ingestion (Im) exceed the load capacity of the medium. The low values for constant k (that may correspond to the adaptability of the food to prey characteristics, such as, size, mobility, etc.) obtained for stages IX, X and XI indicated that Artemia is not an adequate prey and there is necessity of a supplementary diet. The best relationship between predator and prey seemed to occur during stage IV Results obtained in the present work may subsidize future researches and serve as a guideline for practical considerations of feeding rates. (C) 2003 Elsevier B.V. B.V. All rights reserved.

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O objetivo deste trabalho foi avaliar a influência do aguapé como fertilizante orgânico no comportamento alimentar de larvas de tambaqui (Colossoma macropomum) em viveiros de larvicultura. O aguapé foi utilizado para produzir um fertilizante orgânico na proporção de 100 g.m-2. Dois grupos de 5.000 larvas foram transferidos para dois viveiros com e sem fertilizante de macrófita e criados durante um período de 43 dias. O viveiro contendo fertilizante de macrófita apresentou maior abundância de plâncton durante o período de estudo quando comparado ao viveiro controle (P <0,001). A estrutura da comunidade fitoplanctônica não apresentou diferença significativa daquela encontrada no trato digestivo (P > 0,05) e nos viveiros (com e sem fertilizante), evidenciando que as larvas de peixe não apresentaram preferência ou seletividade (P > 0,01) em relação às diferentes algas presentes no viveiro, somente em relação aos organismos zooplanctônicos (P < 0,05). A aplicação de fertilizante aumentou significativamente (P < 0,05) a abundância de fitoplâncton e zooplâncton nos viveiros estudados. O fertilizante de aguapé é fácil de ser obtido e é barato, assim poderá ser utilizado como uma nova alternativa para melhorar a produção dos viveiros de piscicultura.