23736 research outputs found
Sort by
A new species of Ancistrus Kner, 1854 (Siluriformes: Loricariidae) from rio Madeira basin, Amazonas State, Brazil
Get PDFDuring the Mosaico do Apuí expedition in 2006, a new species of Ancistrus was found in the rio Sucunduri, a large tributary of the rio Madeira basin in south Amazonas State. The new species has a unique color pattern for the genus and is distinguished by the presence of alternate light and dark vertical bars on the trunk. Other Ancistrini genera have species with a similar color pattern, but the new species is clearly distinguished by a lack of plates on the snout and presence of fleshy tentacles on the snout as in all Ancistrus representatives. We also provide comments on the taxonomic status of the A. bolivianus, A. heterorhynchus and A. marcapatae. © 2019 Sociedade Brasileira de Ictiologia. All Rights Reserved
Avaliação de fatores microbiológicos do solo e dos efeitos da adubação com magnésio em clones de seringueira em Manaus, Amazonas
Get PDFNative to the Amazon region, the rubber tree [Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell. - Arg.] Is the main source of natural rubber. Its characteristics confer superiority in quality against the synthetic product, combining plasticity, impermeability, electrical insulation, resistance to friction and versatility of applications. Aiming to make possible the expansion of cultivated areas in Brazil, which was already the largest producer of natural rubber, studies with genetic improvement to obtain clones more resistant and productive have been carried out. However, it is of fundamental importance that the principles of plant mineral nutrition be considered throughout this process. Magnesium, for example, is an essential element for the growth and development of plants, also acting in defense mechanisms in situations of abiotic stress. In this sense, the present study aimed to evaluate the dry rubber production of three rubber tree clones and to study the effect of the application of magnesium on soil productivity and biological attributes. The experimental planting of rubber tree is located in the experimental station of the Brazilian Agricultural Research Corporation – Embrapa CPAA, Manaus – AM. It consists of clones originating from interspecific crosses with approximately 20 years of age. The evaluations in the area were carried out during the period from November 2017 to July 2018 and fertilization consisted in the application of increasing doses of Mg (20,25; 40,50 and 81 g plant–1 ) in the clones, with the dose of 40,50 g treatment control. The panels were stimulated over a period of 2 months, and then the application of Ethrel was started quarterly for the beginning of quantification of dry rubber. The production record per clone was performed through the mass of latex coagulated in the bowls, which after natural drying had their dry mass measured. Latex physiological parameters were analyzed: concentrations of sulfur (R– Sh), inorganic phosphorus (P), sucrose (Sac), lutoids rupture index (IRL), magnesium (Mg). The experimental data were analyzed in randomized blocks, with 3 blocks, and submitted to analysis of variance. For the determination of the microbial biomass (BMC), basal respiration (RB) and metabolic quotient (qCO2), the soil was collected in depth of 0 – 20 cm with the aid of Dutch soil and processed in the field in a 4 mm and packed in plastic bags. The experimental data were analyzed in randomized blocks, with 4 blocks, and submitted to analysis of variance. Significant correlations were observed between variables related to dry rubber production (inorganic phosphorus and thiols) and latex flow (sucrose and magnesium concentrations) at the 81 g plant–1 dose for the CPAA clone C01. Regarding the microbiological analyzes, it was observed, through the values of qCO2, that the CPAA C01 clone presents a higher balance and lower CO2 loss to the atmosphere compared to the CPPA C06 and CPAA C45 clones. In the evaluated experimental conditions, the application of magnesium sulphate as an isolated factor did not affect the dry rubber productivity of the studied rubber tree clones, however, it is a necessary practice for the replacement of the nutrients removed from the soil when the rubber tree is harvested.Nativa da região amazônica, a seringueira [Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell. - Arg.] é a principal fonte de borracha natural. Suas características conferem superioridade na qualidade frente ao produto sintético, combinando plasticidade, impermeabilidade, isolamento elétrico, resistência a fricção e versatilidade de aplicações. Visando viabilizar a expansão das áreas de cultivo no Brasil, que já foi o maior produtor de borracha natural, estudos com melhoramento genético para obtenção de clones mais resistentes e produtivos vem sendo realizados. Entretanto, é de fundamental importância que os princípios da nutrição mineral de plantas sejam considerados ao longo desse processo. O magnésio, por exemplo, é um elemento essencial para o crescimento e desenvolvimento das plantas, atuando ainda, nos mecanismos de defesa em situações de estresse abiótico. Nesse sentido, o presente estudo teve como objetivo, avaliar a produção de borracha seca de três clones de seringueira e estudar o efeito da aplicação de magnésio na produtividade e nos atributos biológicos do solo. O plantio experimental de seringueira está localizado na Estação experimental da Empresa Brasileira de Pesquisa Agropecuária – Embrapa CPAA, Manaus–AM. É constituído por clones oriundos de cruzamentos interespecíficos com aproximadamente 20 anos de idade. As avaliações na área foram realizadas durante o período de novembro de 2017 a julho de 2018 e a fertilização consistiu na aplicação de doses crescentes de Mg (20,25; 40,50 e 81 g planta–1) nos clones, sendo a dose de 40,50 g o tratamento controle. Os painéis foram estimulados durante um período de 2 meses, e então iniciou-se a aplicação de Ethrel trimestralmente, para o início da quantificação de borracha seca. O registro da produção por clone foi realizado através da massa de látex coagulado nas tigelas, que após secagem natural tiveram a sua massa seca aferida. Foram realizadas análises de parâmetros fisiológicos do látex: concentrações de enxofre (R-Sh), fósforo inorgânico (P), sacarose (Sac), índice de ruptura de lutóides (IRL), magnésio (Mg) e conteúdo de borracha seca (DRC). Os dados experimentais foram analisados em blocos casualisados, com 3 blocos, e submetidos à análise de variância. Para a determinação da biomassa microbiana (CBM), respiração basal (RB) e quociente metabólico (qCO2), o solo foi coletado em profundidade de 0 – 20 cm com o auxílio de trado holandês e processado ainda em campo em peneira com malha de 4 mm e acondicionadas em sacos plásticos. Os dados experimentais foram analisados em blocos casualisados, com 4 blocos, e submetidos à análise de variância. Foram observadas correlações importantes entre variáveis relacionadas à produção de borracha seca (fósforo inorgânico e tióis) e escoamento de látex (sacarose e concentrações de magnésio) na dose 81 g planta–1 para o clone CPAA C01. Quanto às análises microbiológicas, foi observado, através dos valores de qCO2, que o clone CPAA C01 apresenta maior equilíbrio e menor perda de CO2 para a atmosfera em comparação aos clones CPPA C06 e CPAA C45. Nas condições experimentais avaliadas, a aplicação de sulfato de magnésio como fator isolado, não afetou a produtividade de borracha seca dos clones de seringueira estudados, entretanto, é uma prática necessária para a reposição dos nutrientes retirados do solo quando da explotação do seringal
Revisão taxonômica de Alvarengiini Frey, 1975 (Coleoptera: Melolonthidae: Rutelinae)
No full textAlvarengiini Frey, 1975 was long neglected and omitted in recent works. In order to solve the problems and to establish the limits of the tribe under a taxonomic overview, in the present revision two synonyms were proposed: Alvarengius silphoides Frey, 1975 sin. nov. for Ottokelleria dispar (Burmeister, 1847), and as a consequence of that act, Alvarengius Frey, 1975 sin. nov. for Ottokelleria d’Andretta & Martínez, 1957; a genus has been described for the first time: Carinochilus gen. nov. to allocate C. marginatus (Burmeister, 1847) comb. nov. and two new species, C. gnathidium sp. nov. and C. macrostipes sp. nov.; and the lectotype for O. dispar was designated. All the taxa were defined and illustred; identification keys for tribes, genera and species were provided supplementary to the comparative notes, and distributional data ware added. Alvarengiini has 4 species in two genera, distributed from Bahia (BA) in the Northeast, to Paraná (PR) in the South of Brazil, found in areas of Atlantic Forest.Alvarengiini Frey, 1975 foi por longo tempo negligenciada e omitida em trabalhos recentes. A fim de solucionar os problemas e estabelecer os limites da tribo sob uma ótica taxonômica, na presente revisão foram propostas duas sinonímias: Alvarengius silphoides Frey, 1975 sin. nov. para Ottokelleria dispar (Burmeister, 1847), e em consequência desse ato, Alvarengius Frey, 1975 sin. nov. para Ottokelleria d’Andretta & Martínez, 1957; um gênero foi descrito pela primeira vez: Carinochilus gen. nov. para alocar C. marginatus (Burmeister, 1847) comb. nov. e mais duas espécies: C. gnathidium sp. nov. e C. macrostipes sp. nov.; e o lectótipo para O. dispar foi designado. Todos os táxons foram definidos e ilustrados; chaves de identificação para tribos, gêneros e espécies foram fornecidas supletivamente às notas comparativas, e novos dados distribucionais foram adicionados. Alvarengiini possui 4 espécies em dois gêneros, distribuídas desde a Bahia (BA) no Nordeste, até o Paraná (PR) no Sul do Brasil, encontradas em áreas de Mata Atlântica
Estudo das Propriedades tecnologicas da madeira de murici (Byrsonima crispa Juss. - Malpighiaceae
No full textCaracterização citogenética em espécies de Cichla Bloch & Schneider, 1801 (Perciformes, cichlidae) com ênfase nos híbridos interespecíficos
Get PDFThe genus Cichla comprises 15 valid species, known as tucunare, that are distributed throughout the Amazon. Some species were introduced in different Brazilian river basins, where they had a good adaptation. Studies show the existence of interspecific hybrids in environments where more than one species of this genus occurs. Hybridization is a common process among fish species and backcrossing with the parental is a phenomenon that, when it occurs, can lead to introgression of genes. This process is also common among different strains, particularly when allopatric species are introduced into new habitats. In order to investigate the existence of hybrids among species of this genus, we collected individuals of different species (C. kelberi, C. monoculus, C. pinima, C. piquiti, C. temensis, C. vazzoleri) at different sites in the Amazon basin. We analyzed cytogenetically and all individuals presented 2n = 48 acrocentric chromosomes. The constitutive heterochromatin was found preferentially in centromeric and terminal regions, with variations among individuals of C. monoculus from different locations. This intraspecific variability in the heterochromatic pattern may be the result of adaptation and / or epigenomic responses of the chromatin to changes in the environment due to its wide distribution in the Amazon. The nucleolus organizer region (Ag-NOR) was found in pair 2, coincident with 18S rDNA, in all individuals analyzed, however, the 5S rDNA presented two patterns: in the 4th and 6th pair. Among all individuals, three were considered hybrids, morphologically, collected at the Balbina UHE, together with C. temensis, C. monoculus and C. vazzoleri. For cytogenetics, these individuals differed in relation to the C-band pattern, that was like C. monoculos from Anavilhanas, and the rDNA 5s, that was found in one individual at the first chromosome of 4th pair and in the second chromosome of 6th pair (C. temensis ou C. monoculus X C. vazzoleri),. Another individual presented rDNA 5s at 4th chromosomal pair (C. temensis X C. monoculus), and the last hybrid presented the rDNA 5s at the second chromosome of 4th and 6th pair (C. temensis ou C.monoculos X C. vazzoleri), allowing us to suggest the possible parenting of hybrids. The telomeric sites were restricted to the terminal regions of the chromosomes and the Rex3 and Rex6 retrotransposons showed a dispersed distribution pattern in heterochromatin and eucromatin portions.O gênero Cichla compreende 15 espécies válidas, conhecidas como tucunaré, que se distribuem por toda Amazônia. Algumas espécies foram introduzidas em diferentes bacias hidrográficas brasileiras, onde tiveram uma boa adaptação. Alguns estudos têm apontado a existência de híbridos interespecíficos, em ambientes onde ocorrem mais de uma espécie deste gênero. Ainda, pode ocorrer o retrocruzamento com os parentais, fenômeno que pode levar à introgressão de genes. Este processo também é comum entre diferentes linhagens, particularmente quando espécies alopátricas são introduzidas em novos habitats. A fim de investigar a existência de híbridos entre as espécies deste gênero, nós coletamos indivíduos de diferentes espécies de tucunaré (C. monoculus, C. temensis, C. pinima, C. kelberi, C. piquiti, C. vazzoleri) em diferentes locais da bacia amazônica. Estes foram analisados citogeneticamente, e todos os indivíduos apresentaram 2n=48 cromossomos acrocêntricos. A heterocromatina foi encontrada preferencialmente em regiões centroméricas e terminais, com variações entre indivíduos de Cichla monoculus, de diferentes locais. Essa variabilidade intraespecífica no padrão heterocromático pode ser o resultado de adaptação e/ou respostas epigenômicas da cromatina a mudanças no ambiente, devido a sua ampla distribuição pela Amazônia. A região organizadora do nucléolo (RON) foi localizada no par 2, coincidente com DNAr 18S, em todos os indivíduos analisados. O DNAr 5S, entretanto, apresentou dois padrões: no 4º e no 6º par. Entre todos os indivíduos, três foram considerados híbridos, morfologicamente, coletados na UHE de Balbina, junto com C. temensis, C. monoculus e C. vazzoleri. Do ponto de vista citogenético, estes indivíduos se diferenciaram em relação ao padrão de banda C, que mostrou-se similar entre híbridos e a C. monoculus coletado em Anavilhanas e em relação à localização do DNAr 5S, que em um indivíduo esteve em posição intersticial no primeiro cromossomo do par 4 e no segundo cromossomo do par 6 (C. temensis ou C. monoculus X C. vazzoleri), em outro indivíduo, a marcação do DNAr 5S se fez presente em ambos os cromossomos do par 4 (C. temensis X C. monoculus) e num terceiro indivíduo, a marcação evidenciou o segundo cromossomo dos pares 4 e 6 (C. temensis ou C. monoculus X C. vazzoleri), o que nos permite sugerir os possíveis parentais dos híbridos. Os sítios teloméricos foram restritos às regiões terminais dos cromossomos e os retrotransposons Rex3 e Rex6 apresentaram um padrão de distribuição disperso em porções de heterocromatina e eucromatina
Digestive enzymes and parasitology of Nile tilapia juveniles raised in brackish biofloc water and fed with different digestible protein and digestible energy levels
No full textBiofloc technology (BFT) system is increasing around the world and Nile tilapia is suggested as the major fish species for such technology. The objective of this study was to evaluate diets with different levels of digestible protein (22, 26 and 30% DP) and digestible energy (3000, 3150 and 3300 kcal kg −1 ) for Nile tilapia juveniles raised in brackish biofloc system water (10 ppt) and its effects on the activity of digestive enzymes and the presence of ectoparasites in the gills. Tilapia juveniles (1.25 ± 0.15 g of initial weight) were stocked in thirty-two experimental units (100 L tanks) with 15 fish per tank. After 42 days fish were harvested, sampled and analyzed. The pepsine (stomach) and trypsine (intestine) activities significantly increased according to the increase of dietary levels. For both cases the higher activity was observed in 30% DP treatment (P < 0.05), with (pepsine) and without interaction (trypsine) with digestible energy levels. The opposite trend was observed for chymotripsine activity (intestine), in which 22% DP presented the higher activity, with significant interaction with energy levels. The higher activity for intestinal lipase activity was observed in 3150 kcal kg −1 . No difference was found for ectoparasite analyses in gills between the treatments. Although in all treatments monogea type was found (70–90% of prevalence), the number of parasites per fish was low in all treatments (<1.6 parasites fish −1 ). The results suggested that differences in dietary digestible protein and digestible energy affected the activity of digestive enzymes in Nile tilapia juveniles raised in biofloc with 10 ppt of salinity. On the other hand, biofloc system did not promote ectoparasite spread even with low dietary levels of digestible protein and digestible energy. © 2019 Elsevier B.V
ATLANTIC-PRIMATES: a dataset of communities and occurrences of primates in the Atlantic Forests of South America
Get PDFPrimates play an important role in ecosystem functioning and offer critical insights into human evolution, biology, behavior, and emerging infectious diseases. There are 26 primate species in the Atlantic Forests of South America, 19 of them endemic. We compiled a dataset of 5,472 georeferenced locations of 26 native and 1 introduced primate species, as hybrids in the genera Callithrix and Alouatta. The dataset includes 700 primate communities, 8,121 single species occurrences and 714 estimates of primate population sizes, covering most natural forest types of the tropical and subtropical Atlantic Forest of Brazil, Paraguay and Argentina and some other biomes. On average, primate communities of the Atlantic Forest harbor 2 ± 1 species (range = 1–6). However, about 40% of primate communities contain only one species. Alouatta guariba (N = 2,188 records) and Sapajus nigritus (N = 1,127) were the species with the most records. Callicebus barbarabrownae (N = 35), Leontopithecus caissara (N = 38), and Sapajus libidinosus (N = 41) were the species with the least records. Recorded primate densities varied from 0.004 individuals/km 2 (Alouatta guariba at Fragmento do Bugre, Paraná, Brazil) to 400 individuals/km 2 (Alouatta caraya in Santiago, Rio Grande do Sul, Brazil). Our dataset reflects disparity between the numerous primate census conducted in the Atlantic Forest, in contrast to the scarcity of estimates of population sizes and densities. With these data, researchers can develop different macroecological and regional level studies, focusing on communities, populations, species co-occurrence and distribution patterns. Moreover, the data can also be used to assess the consequences of fragmentation, defaunation, and disease outbreaks on different ecological processes, such as trophic cascades, species invasion or extinction, and community dynamics. There are no copyright restrictions. Please cite this Data Paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data. © 2018 by the The Authors. Ecology © 2018 The Ecological Society of Americ
Frequência Da Mutação Val1016Ile No Gene Kdr E Análise Da Variabilidade Genética Em Populações De Aedes Albopictus Na Cidade De Manaus, Com Base Em Marcadores Rapd.
No full textGEEA - Caderno de Debates: TOMO XV
No full textEste tomo trata de temas altamente relevantes para a Amazônia: Terra Preta de Índio e Sustentabilidade & Desenvolvimento. O primeiro é uma herança indígena à disposição da sociedade modern
A new record and emended description of a rare Amazonian white-sand species: Schoepfia clarkii (Schoepfiaceae)
No full textSchoepfia clarkii is a rare species of Schoepfiaceae that to date has been known only from the single flowering specimen used in the original description from white-sand vegetation in Venezuela. Here we report new records for this species collected from the lower Negro River basin in Brazil, ca. 900 km from the type locality, but also from white-sand vegetation. We provide a more detailed description of the species, including the first observations of fruit characters, as well as illustrations, photographs, a distribution map, and discussion of its conservation status. We also provide a key for the identification of the South American species of Schoepfia. © 2019, The New York Botanical Garden