999 resultados para ecologia da germinação
Resumo:
Teve-se o objetivo de avaliar as formas de se misturar o lubrificante sólido grafite nas sementes de milho, as dosagens e a influência desse na distribuição longitudinal e na germinação, em sementes sem e com tratamento fitossanitário, em mecanismo dosador com disco perfurado horizontal. Os fatores analisados foram: distribuição longitudinal das sementes (espaçamentos falhos, múltiplos e aceitáveis) e a porcentagem de germinação aos 7 e aos 14 dias após a instalação no germinador. Concluiu-se que o tratamento fitossanitário aumentou os espaçamentos falhos e múltiplos e reduziu os espaçamentos aceitáveis. O emprego de grafite reduziu os espaçamentos falhos e múltiplos e elevou os espaçamentos aceitáveis. A melhor forma de mistura do grafite ocorreu na máquina de tratamento fitossanitário de sementes. A distribuição longitudinal alcançou seu ponto ótimo com a dosagem de grafite de 3,37 g kg-1 de semente. As variáveis tratamento fitossanitário, mecanismo dosador e grafite não influíram na germinação das sementes de milho.
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The research aims to evaluate the contributions of a teaching unit to enhance the learning contents ecological green areas in elementary school. The work was conducted with elementary students in a public school in Natal-RN. We sought to identify the students´ previous knowledge about the contents of ecology, develop and implement a Potentially Meaningful Teaching Units PMTU; assess learning of ecological concepts in Teaching Unit Potentially Significant; assess the contribution of interpretative trail as strategy teaching to learning content ecology. The survey of students´ previous knowledge through the pre-test was essential to identify the appropriate subsumers and partially correct, since they served as "anchor" for further expansion of scientific concepts contained in this research. The green areas of the school as an educational, contributed the motivational aspect, as students were protagonists throughout the entire process of teaching and learning. The method of stimulated memory was effective to evidence learning ecological concepts in interpretive trails. The use of diverse activities organized on a PMTU promoted intellectual autonomy of the students and facilitated the acquisition of new meanings through progressive differentiation, and integrative reconciliation consolidation of ecological content and concepts related to biotic and abiotic factors on the basis of the central ideas thematic Life and Environment. The development of procedural skills to capture and share meanings, observe, collect and record data, hypotheses, ability to explain, to apply knowledge to solve problem situations, argue, identify, compare, differentiate and relate concepts, negotiate meanings, reflecting Critically, systematize data was evidenced. Collaborative activities promoted the incorporation of attitudinal contents as developing respect for differences, learn to work in teams to plan, develop and implement actions together for citizenship and environmental responsibility. The application of the Potentially Meaningful Teaching Units PMTU showed evidence of Critical meaningful learning ecological concepts covered in elementary school.
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This study investigated factors that influence the group size during the behavior foraging of estuarine dolphin Sotalia guianensis in the coast south of the state Rio Grande do Norte (RN), it also characterized the diet of estuarine dolphins and elaborated an otoliths catalog for aid in the identification of the preys found in the stomach contents. In relation to the group size during behaviour foraging, inside of the Curral Bay, larger frequency of solitary hunt was observed. Factors as tide variation, group composition and seasons didn't present correlation with the number of animals observed during a feeding episode. Capture success for participant was shown significantly larger when the animals hunted alone, what possibly explains the largest frequency of solitary hunt inside of the Curral Bay. About diet, were identified 18 bone fishes species, with predominance of species the families Haemulidae and Sciaenidae and five cephalopods species, including two new species in the diet of Sotalia guianensis in Brazil. Our results indicated that estuarine dolphin in the coast oriental from Rio Grande do Norte (RN) feeds predominantly of fish that form shoal, of habitat estuarino and producing of sounds. The analysis of the images, otoliths of 43 species of coastal fish of the coast of the state of Rio Grande do Norte (RN), aided by the offered descriptions, demonstrated to be an effective methodology for the knowledge of those structures, as well as it represented a form of reducing the subjectivity in the identification of the bone fishes found in stomach content
Resumo:
This study evaluated the spatial, time and alimentary niches of Tropidurus hispidus and Tropidurus semitaeniatus in sympatry in a caatinga of Rio Grande do Norte, Brazil, as well as their foraging and termoregulatory behaviors, the activity body temperature and their reproductive and fat body cycles. Monthly excursions, from October 2006 to May 2008, were conducted at the Ecological Station of the Seridó (ESEC Seridó), Serra Negra do Norte municipality, using specific methodology for investigation of the aforementioned objectives. The two species presented similarities in space niche use, mainly in rocky habitat, however they differed in vertical microhabitat use with T. hispidus using a larger vertical microhabitat range. In the dry season the time of activity of both species was bimodal. In the wet season T. semitaeniatus showed a unimodal activity period, while T. hispidus maintained an bimodal activity period. In terms of importance in the diet, to both species, Hymenoptera/Formicidae and Isoptera predominated during the dry season. In the wet season, although Hymenoptera/Formicidae had larger importance among the prey items, lizards opportunistically predated on Lepidoptera larvae, Coleoptera larvae/adults and Orthoptera nymphs/adults. The foraging intensity revealed differences between the species, mainly in the wet season, when T. semitaeniatus was more active than T. hispidus. The mean activity body temperature of T. semitaeniatus was significantly higher than that of T. hispidus. The thermoregulatory behavior showed that during the dry season T. hispidus and T. semitaeniatus spent more time in shade or under filtered sun. In the wet season, T. hispidus did not show differences in the amount of time spent among the light exposure locations, however T. semitaeniatus spent most of their time exposed to direct sun or filtered sun. The reproductive cicle of T. hispidus and T. semitaeniatus occurred from the middle of the dry season to the beginning of the wet season. In both species, female reproductive activity was influenced by precipitation, whereas males exhibited spermatozoa in their testes throughout the year, and their reproductive activity was not related with any of the climatic variables analysed. In the two species, the fat storage varied inversely with reproductive activity, and there was no difference in fat body mass between females and males. We concluded that the segregation between T. hispidus and T. semitaeniatus in this caatinga area occurs in vertical space use, in the largest vagility of T. hispidus in microhabitat use and larger range size of their alimentary xviii items. Additionally, significant seasonal differences in relation to the activity period, body temperature, and foraging and termoregulatory behaviors between these two Tropidurus species facilitate their coexistence.
Resumo:
Lemon sharks, Negaprion brevirostris, are common in the Fernando de Noronha Archipelago, but detailed information about the species in this site is lacking. The aim of this study was to describe the spatial distribution, grouping behavior, habitat use and behavioral ecology of juvenile lemon sharks in the archipelago, and their interaction with some environmental and ecological factors. During 2006 and 2007, the presence and spatial distribution of juvenile sharks were quantified through scuba diving and snorkeling at several sites of the archipelago. In 2008 the habitat use of juvenile sharks was quantified through visual census while snorkeling along 300 x 8 m strip transects. During these transects the grouping behavior of lemon sharks was quantified by ad libitum. Results indicate that Fernando de Noronha Archipelago is used as a nursery area for lemon sharks, and the parturition occurs from November to April. Juveniles preferred using shallower areas available by the tide variation and formed groups only in the presence of adult conspecifics. This preference for shallower habitats and the group behavior probably are anti-predatory tactics used by juvenile lemon sharks, in response to the low availability of shelter and high predation risk of the studied areas. Quantifications of prey availability and predation risk of juveniles showed that, in general, lemon sharks are trading-off food by security and investing in sites with higher possibility of energetic return. Behavioral observations enabled to record juvenile carangid fishes following juvenile lemon sharks, remora host-parasite and juvenile sharks foraging on schools of herrings and octopuses. We also recorded the behavior of juvenile sharks following conspecifics of similar size, circling with two or three individuals and smaller individuals giving way to larger juveniles. When adults are present, juvenile lemon sharks are more social than solitary, indicating that predation is one of the factors that contribute to social behaviors of the species. Results also suggest that when grouped the juveniles have a hierarchical organization according to body size. Furthermore, observation of large adult females with several fresh mating bites and scars in the same habitats used by juvenile lemon sharks, indicates that Fernando de Noronha Archipelago is used as nursery and mating grounds by this species
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The acoustic ecology concept involve the relation between the live organisms and their sound environment and is applied in the present work to study the context in which the humpback whale (Megaptera novaeangliae) singing behavior, known as the most complex display in the nature, occurred in the northeastern Brazilian coast, outside the core area of Abrolhos Bank, between 2005 and 2010.I analyze the singer male occurrence , their spatial distribution and probable relations with oceanographic features, such as depth, tide regimen and moon phases. I also describe the acoustic structure and temporal variation of the singing behavior, based on song frequency and time measurements outside the Abrolhos Bank, and further compare the song complexity, registered in the same period, between Abrolhos Bank (16°- 19° S, 37°- 39° W) and the adjacent North Coast, herein considered from Itacaré (14° S, 38° W) to Aracaju (11° S, 37° W). Additionally, I look for describe and analyze anthropogenic noise sources in the marine environment of the study area, produced by the oil industry as well as by the whale watching operation, relating their frequencies to the acoustic niche utilized by the humpbacks. The results indicated a great plasticity in the singing behavior, evidenced by the occurrence of singer males in diverse social structures, from solitary individuals to other groups, even containing females and calves, as well as by the diversity which compound the song, when compared between two regions inside the same breeding area, which present distinct oceanographic characteristics. The singer male distribution may be related with the continental shelf extent along the study area. The anthropogenic noise presented frequency range, amplitude and sound intensity in potential to interfere acoustically in the singing behavior of the species, may resulting in disturbance during the breeding season in the Brazilian coast. Implications about the obtained results in the humpback whale mating system are discussed. In this way, I pretend to contribute with the acoustic ecology subject and provide information to subsidize humpback whale conservation
Resumo:
In this thesis I discuss the reproductive behaviour and ecology of the libellulid Diastatops obscura Fabricius, 1775, (Insecta: Odonata) in natural conditions. Populations of this species were studied on the middle stretch of the Pitimbu River, Parnamirim municipality, Rio Grande do Norte, Brazil, during four discontinuous periods between 2002 and 2004. The objectives include the description of strategies and behaviors of both sexes, with especial interest in the intra-male competition for territories and females, the mate selection by females and the importance of male body size and other secondary characters on their reproductive success; from an adaptationist point of view. It was observed that the behavior of males and females in the reproductive areas are interrelated : the males came earlier to compete for the best territories and the females waited the result of that competition to be fertilized by dominants males, which preferably occupied areas near the river margin. The reproductive success of males with territories on the margin, estimated by number of copulations, ovipositions and days acting as territorial, was better than obtained by more separated territorial males and by satellite males. The body size of males is an important factor for the copulation and oviposition taxes and for the number of territorial days, favoring the biggest individuals. I also discuss the apparently importance of wing brilliance and wing integrity on male reproductive success. On inter-sexual relationships, I proved that females of D. obscura participate in mate selection, rejecting non-territorial males or substituting their sperm for other of higher status
Resumo:
This study investigated the influence of intrinsic and extrinsic factors on the feeding ecology and foraging behavior of the whiptail lizard Ameivula aff. ocellifera, a new species widely distributed in the Brazilian Caatinga, and that is in process of description. In attendance to the objectives, the Dissertation was structured in two chapters, which correspond to scientific articles, one already published and the other to be submitted for publication. In Chapter 1 were analyzed the general diet composition, the relationship between lizard size and prey size, and the occurrence of sexual and ontogenetic differences in the diet. Chapter 2 contemplates a seasonal analysis of diet composition during two rainy seasons interspersed with a dry season, and the quantitative analysis of foraging behavior during two distinct periods. The diet composition was determined through stomach analysis of lizards (N = 111) collected monthly by active search, between September 2008 and August 2010, in the Estação Ecológica do Seridó (ESEC Seridó), state of Rio Grande do Norte. Foraging behavior was investigated during a rainy and a dry month of 2012 also in ESEC Seridó, by determining percent of time moving (PTM), number of movements per minute (MPM) and prey capture rate by the lizards (N = 28) during foraging. The main prey category in the diet of Ameivula aff. ocellifera was Insect larvae, followed by Orthoptera, Coleoptera and Araneae. Termites (Isoptera) were important only in numeric terms, having negligible volumetric contribution (<2%) and low frequency of occurrence, an uncommon feature among whiptail lizards. Males and females did not differ neither in diet composition nor in foraging behavior. Adults and juveniles ingested similar prey types, but differed in prey size. Maximum and minimum prey sizes were positively correlated with lizard body size, suggesting that in this population individuals experience an ontogenetic change in diet, eating larger prey items while growing, and at the same time excluding smaller ones. The diet showed significant seasonal differences; during the two rainy seasons (2009 and 2010), the predominant prey in diet were Insect larvae, Coleoptera and Orthoptera, while in the dry season the predominant prey were Insect larvae, Hemiptera, Araneae and Orthoptera. The degree of mobility of consumed prey during the rainy seasons was lower, mainly due to a greater consumption of larvae (highly sedentary prey) during these periods. Population niche breadth was higher in the dry season, confirming the theoretical prediction that when food is scarce, the diets tend to be more generalized. Considering the entire sample, Ameivula aff. ocellifera showed 61,0 ± 15,0% PTM, 2,03 ± 0,30 MPM, and captured 0,13 ± 0,14 per minute. Foraging mode was similar to that found for other whiptail lizards regarding PTM, but MPM was relatively superior. Seasonal differences were verified for PTM, which was significantly higher in the rainy season (66,4 ± 12,1) than in the dry season (51,5 ± 15,6). It is possible that this difference represents a behavioral adjustment in response to seasonal variation in the abundance and types of prey available in the environment in each season
Resumo:
Hylocereus undatus (Haw.), popularmente conhecida como pitaia vermelha é uma cactácea para a qual se tem registrado um aumento de consumo nos últimos anos e, por ser ainda pouco explorada, vários aspectos referentes à sua propagação ainda são desconhecidos. Até o momento, não existem critérios para a execução de testes de germinação para sementes dessa espécie, publicados nas Regras para Análise de Sementes. Nesse sentido, objetivou-se com este trabalho adequar a metodologia quanto ao substrato, temperatura e tempo de contagem inicial e final para o teste de germinação. Foram testados quatro substratos (rolo de papel, areia, vermiculita e solo) e quatro temperaturas (20, 25, 30 e 20-30°C). O efeito dos substratos no desempenho germinativo das sementes foi avaliado pelo teste de germinação e de primeira contagem instalado com quatro subamostras de 50 sementes. Foram feitas contagens diárias do número de plântulas emergidas até atingirem a estabilidade e, no final do experimento, foram avaliados a porcentagem de germinação das sementes, considerando as plântulas normais, anormais e sementes mortas. Concluiu-se que o teste de germinação de sementes de pitaia vermelha deve ser realizado à temperatura constante de 25°C em rolo de papel, com contagens inicial e final aos cinco e dez dias após a semeadura, respectivamente.
Resumo:
Restos vegetais e liteira podem interferir no desenvolvimento de plantas. Este trabalho objetivou avaliar os efeitos alelopáticos de extratos aquosos de Pinus sp., milheto (Pennisetum americanum (L.) Leeke) e mucuna (Stizolobium aterrimum Piper & Tracy) sobre a germinação, colonização micorrízica e crescimento inicial de milho (Zea mays L.), soja (Glycine max L.) e feijão (Phaseolus vulgaris L.). Os extratos foram elaborados utilizando folhas trituradas. O experimento in vitro empregou papel Germitest umedecido com extratos ou água destilada por sete dias. O experimento em casa de vegetação teve esquema fatorial 3 x 3 x 4, com quatro repetições: três espécies vegetais (soja, milho e feijão), três extratos aquosos (Pinus, milheto e mucuna) e quatro doses de extrato (0,0; 0,5; 1,0; e 2,0 kg L-1). O substrato foi Latossolo Vermelho coletado no município de Selvíria-MS, no bioma Cerrado. Após a semeadura, os vasos receberam, a cada cinco dias, por 45 dias, 50 mL dos extratos. Para a soja, extratos de mucuna e milheto diminuíram o comprimento do hipocótilo e da radícula e os de Pinus aumentaram esses comprimentos. em feijão, o extrato de Pinus diminuiu o comprimento do hipocótilo e da radícula, mas os extratos de mucuna e milheto aumentaram-no. O extrato do milheto reduziu a percentagem e a velocidade de germinação em feijão. Todos os extratos reduziram a colonização micorrízica e o número de esporos de fungos micorrízicos arbusculares em soja, milho e feijão.
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The world`s ecology crisis has in the capitalism way of production one of the possible causes. The unstopped search for the profits, into unlimited exploration of limited resources, made a huge transformation in human relationships with the nature, causing environment devastation, shortage of resources and species disappearance. Arises the necessity of question the society model that we are and which brings this crisis state, while we are impelled to search an alternative way. The ecosociallist praxis blows marxist principles with ecological matters, bringing important contributions regarding alternatives to capital/exploratory modus, advocating for a social fair society and environmentally sustainable. This way, by bibliographic review, we will research about this theory which have been growing in academic middles. In the same way, we will analyze the rural social movements paper in the construct of this reality. Throut the half estruture interviwes, bibliografic research and visities in the space of settlement called Moacir Lucena, that is today a exemple of rural resignification
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FUNDAMENTOS: Tinea capitis é importante infecção fúngica de interesse dermatológico e pediátrico. No Brasil sua prevalência é desconhecida, e os agentes causais principais são o Trichophyton tonsurans nas regiões Norte-Nordeste e o Microsporum canis no Sul-Sudeste do país. Conhecimento sobre gênero e espécies mais prevalentes tem importância sanitária e terapêutica. OBJETIVOS: Identificar espécies de dermatófitos, causa de Tinea capitis, em serviço universitário que atende clientela do Sistema Único de Saúde, de procedência urbana e rural, no interior do Estado de São Paulo. MÉTODOS: Amostras de casos clínicos suspeitos de Tinea capitis, procedentes da área de abrangência da Faculdade de Medicina de Botucatu-Unesp, foram investigadas por exame direto e cultivo visando ao diagnóstico e isolamento do agente causal. RESULTADOS: de 1.055 suspeitas, 594 foram confirmadas por exame direto, em 364 (61,1%) isolou-se o agente: M. canis em 88,2%, seguindo-se T. tonsurans (4,7%), T. rubrum (3,3%), M. gypseum (1,9%), T. mentagrophytes (1,6%). O sexo masculino correspondeu a 55,7% dos casos, e a faixa etária entre 0-5 anos predominou com 62,6% (p < 0,05). CONCLUSÕES: A prevalência detectada do M. canis superou o esperado para a Região Sudeste do Brasil. A freqüência de 88,2% pode estar influenciada por pacientes procedentes da zona rural. Esse dado deve ser considerado quando de decisão terapêutica.
Resumo:
Coastal and marine protected areas are created to protect habitat, avoid biodiversity loss, and to help maintain viable fisheries. However, most of these areas in tropical countries occurs in impoverished regions and directly affect the livelihood and survival of coastal communities which directly depend on fisheries and shellfisheries. Therefore, socioeconomic and conservation goals overlap. In this context, fishers should have a central place in resource management. They are critical resource users and their behavior directly affects the system. Shellfish resources are important sources of food, employment and income to fishing communities in Latin America. But despite its widespread use for food and income, there is an urgent need of more research on shellfish management. This research discusses the artisanal fisheries of Venus clam (Anomalocardia brasiliana) (Gmelin, 1791) (Bivalvia: Veneridae) in Brazil, and points out strategies to improve the system. Venus clam is a small and commonly exploited species for food and income on the Brazilian coast. This research was carried out at Ponta do Tubarão Sustainable Development Reserve (Brazilian Northeast coast), where there was no information available about who harvest, where or how much Venus clam has been harvested, despite this resource being exploited for generations. Clam fishery follows the pattern of socio-economic invisibility that general clam exploitation has in Brazil. Methods used were interviews, participatory monitoring and focal follow observation from January 2010 to May 2011. Results include: (a) the identification of shell fishers, (b) how harvest and meat processing are performed (mollusk beds, time spent, gross and net production), (c) the analisis of shell fisher income and their economic sustentability, and (d) the involvement of shell fisher families in data gathering and analyses for the first time. Based on the acquired knowledge, we propose a new institutional arrangement for clam fishery including co-management, fisheries agreement, compensatory arrangements and improvements for the Venus clam value chain such as the establishment of a minimum price for clam meat. This research also includes two other results: a general description for Venus clam harvesting in the Brazilian Northeast coast and a specific discussion about co-management of Venus clam in Brazil. The first one was possible through the meeting of several shell fisherwomen from other states during activities promoted by People of the Tides (PoT) project. PoT was an international initiative aiming to develop coastal communities that depend on mollusk for their livelihood. The second one is a comparison between PoT and Venus clam management at Pirajubaé Marine Extractive Reserve (Santa Catarina). It evaluates the success and failures of these only two initiatives involving co-management of A. brasiliana in Brazil
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Novos estimulantes vegetais têm merecido estudos por possuírem alto potencial para melhorarem a produtividade de culturas. Triacontanol, um álcool alifático primário de cadeia longa isolado de vegetais encontra-se dentre essas substâncias. Com o objetivo de verificar o efeito deste estimulante vegetal sob condições de laboratório, sementes de Zea mays cv. C-525 e Lycopersicon esculentum cv. Kada foram submetidas aos efeitos de 10 ml de triacontanol 0,01, 0,1 e 1 mg. 1-1, além do controle, em caixas de Petri. Observações realizadas 7 e 14 dias após a instalação do ensaio mostraram que concentrações crescentes de triacontanol tendem a aumentar o crescimento da radícula e do hipocótilo do tomateiro, 14 dias após a aplicação. Nesta data notou-se também que concentrações crescentes de triacontanol tendem a incrementar o desenvolvimento do hipocótilo do milho.
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Reguladores e estimulantes vegetais tem sido utilizados nas condições dos trópicos sem a verificação de seus efeitos sob condições controladas, levando frequentemente ao mascaramento de seus efeitos pelas condições do agroecossistema. Com a finalidade de observar os efeitos dessas substâncias sob condições de laboratório, sementes de Zea mays cv. C-525 e Lycopersicon esculentum cv. Kada foram submetidas aos efeitos de giberelina 100 ppm, chlormequat 2000 ppm, hidrazida maleica 1000 ppm, Agrostemin 1,25 g. l-1 e Atonik 0,5 ml.1-1, além do controle, em caixas de Petri. Observações realizadas 7 e 15 dias após a instalação do ensaio mostraram que giberelina e Agrostemin promoveram aumento no crescimento da radícula e do hipocótilo de milho e tomateiro. Hidrazida maleica inibiu o desenvolvimento da radícula das plântulas de milho. Hidrazida maleica e Atonik tenderam a reduzir o crescimento da radícula e do hipocótilo de tomateiro.