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81.
Grazielle Furtado Moreira Elder Sim?es de Paula Batista Henrique Borges Neves Campos Raphael Emilio Lemos Marcelo da Costa Ferreira 《PloS one》2013,8(6)
The objective of this study was to evaluate different strategies for the application of entomopathogenic nematodes (EPN). Three different models of spray nozzles with air induction (AI 11003, TTI 11003 and AD-IA 11004), three spray pressures (207, 413 and 720 kPa), four different additives for tank mixtures (cane molasses, mineral oil, vegetable oil and glycerin) and the influence of tank mixture stirring time were all evaluated for their effect on EPN (Steinernema feltiae) viability and pathogenicity. The different nozzles, at pressures of up to 620 kPa, were found to be compatible with S. feltiae. Vegetable oil, mineral oil and molasses were found to be compatible adjuvants for S. feltiae, and stirring in a motorized backpack sprayer for 30 minutes did not impact the viability or pathogenicity of this nematode. Appropriate techniques for the application of nematodes with backpack sprayers are discussed. 相似文献
82.
Ivana Lemos Souza Rosangela Cristina Marucci Luis Claudio Paterno Silveira Nágila Cristina Paixão de Paulo Jana C. Lee 《BioControl》2018,63(4):543-553
Marigolds (Tagetes erecta L.) suppress nematodes and are attractive companion plants, but their role in biological control is unknown. We evaluated how exposure to marigold blooms impacts the aphid parasitoid, Aphidius platensis Brethes. Female wasps previously exposed to marigold spent more time walking and parasitizing Myzus percisae Sulzer or Schizaphis graminum Rodani aphids, and subsequently had higher parasitism rates. Meanwhile, completely starved wasps spent more time stationary and marginally more time grooming. Time spent probing, emergence rate, and sex ratio were not affected. Wasp survival was best on honey, followed by marigold, and lowest on non-blooming marigolds. Nutrient reserves of wasps given honey, aphid-infested marigold, or marigold alone were compared to newly-emerged unfed wasps. Their resulting lipid, glycogen and sugar levels were similar, suggesting that these foods helped wasps maintain reserves similar to emergence levels. These results suggest that marigold may improve biological control of aphids by A. platensis. 相似文献
83.
Adones Sales Luana Ferreira Afonso Juliana Alves Americo Mauro de Freitas Rebelo Glaucia Maria Pastore Juliano Lemos Bicas 《Biotechnology letters》2018,40(3):561-567
Objective
To investigate the biocatalytic potential of Colletotrichum acutatum and Colletotrichum nymphaeae for monoterpene biotransformation.Results
C. acutatum and C. nymphaeae used limonene, α-pinene, β-pinene, farnesene, citronellol, linalool, geraniol, perillyl alcohol, and carveol as sole carbon and energy sources. Both species biotransformed limonene and linalool, accumulating limonene-1,2-diol and linalool oxides, respectively. α-Pinene was only biotransformed by C. nymphaeae producing campholenic aldehyde, pinanone and verbenone. The biotransformation of limonene by C. nymphaeae yielded 3.34–4.01 g limonene-1,2-diol l?1, depending on the substrate (R-(+)-limonene, S-(?)-limonene or citrus terpene (an agro-industrial by-product). This is among the highest concentrations already reported for this product.Conclusions
This is the first report on the biotransformation of these terpenes by Colletotrichum spp. and the biotransformation of limonene to limonene-1,2-diol possibly involves enzymes similar to those found in Grosmannia clavigera.84.
Marcos Vinicius Antunes de Lemos Elisa Peripolli Mariana Piatto Berton Fabiele Loise Braga Feitosa Bianca Ferreira Olivieri Nedenia Bonvino Stafuzza Rafael Lara Tonussi Sabrina Kluska Hermenegildo Lucas Justino Chiaia Lenise Mueller Adrielli Mathias Ferrinho Angelica Simone Cravo Prereira Henrique Nunes de Oliveira Lucia Galvão de Albuquerque Fernando Baldi 《Journal of applied genetics》2018,59(2):203-223
The aim of this study was to analyze the association between the copy number variation regions (CNVRs) and fatty acid profile phenotypes for saturated (SFA), monosaturated (MUFA), polyunsaturated (PUFA), ω6 and ω3 fatty acids, PUFA/SFA and ω6/ω3 ratios, as well as for their sums, in Nellore cattle (Bos primigenius indicus). A total of 963 males were finished in feedlot and slaughtered with approximately 2 years of age. Animals were genotyped with the BovineHD BeadChip (Illumina Inc., San Diego, CA, USA). The copy number variation (CNV) detection was performed using the PennCNV algorithm. Log R ratio (LRR) and allele B frequency (BAF) were used to estimate the CNVs. The association analyses were done using the CNVRuler software and applying a logistic regression model. The phenotype was adjusted using a linear model considering the fixed effects of contemporary group and the animal age at slaughter. The fatty acid profile was analyzed on samples of longissimus thoracis muscle using gas chromatography with a 100-m capillary column. For the association analysis, the adjusted phenotypic values were considered for the traits, while the data was adjusted for the effects of the farm and year of birth, management groups at birth, weaning, and superannuation. A total of 186 CNVRs were significant for SFA (43), MUFA (42), PUFA (66), and omega fatty acid (35) groups, totaling 278 known genes. On the basis of the results, several genes were associated with several fatty acids of different saturations. Olfactory receptor genes were associated with C12:0, C14:0, and C18:0 fatty acids. The SAMD8 and BSCL2 genes, both related to lipid metabolic process, were associated with C12:0. The RAPGEF6 gene was found to be associated with C18:2 cis-9 cis-12 n-6, and its function is related to regulation of GTPase activity. Among the results, we highlighted the olfactory receptor activity (GO:0004984), G-protein-coupled receptor activity (GO:0004930), potassium:proton antiporter activity (GO:0015386), sodium:proton antiporter activity (GO:0015385), and odorant-binding (GO:0005549) molecular functions. A large number of genes associated with fatty acid profile within the CNVRs were identified in this study. These findings must contribute to better elucidate the genetic mechanism underlying the fatty acid profile of intramuscular fat in Nellore cattle. 相似文献
85.
Manihot alterniflora and M. elongata spp. nov. (Euphorbiaceae) and the rediscovery of M. quinquefolia in Caatinga (semiarid) vegetation in Brazil
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Márcio Lacerda Lopes Martins Paulo Cezar Lemos de Carvalho Carlos Alberto da Silva Ledo André Márcio Amorim 《Nordic Journal of Botany》2018,36(3)
We describe and illustrate two species of Manihot that occur in Caatinga (semiarid) vegetation in Brazil and redescribe and lectotypify M. quinquefolia Pohl, which was only known from a single collection made by J. E. B. Pohl in 1827. Manihot elongata P.Carvalho & M.Martins is widely distributed and Manihot alterniflora P.Carvalho & M.Martins is endangered because of its small populations and restricted area of occurrence. We establish M. quinquefolia as the only species of Manihot in the Caatinga with compound leaves. An identification key is provided for the 13 species of Manihot present in the Caatinga. 相似文献
86.
M A D Ferreira Osmar D R H Nunes Juvenia B Fontenele Otília D L Pessoa Telma L G Lemos Glauce S B Viana 《Phytomedicine》2004,11(4):315-322
In the present work we studied the antinociceptive and antiedematogenic effects of a quinone fraction (QF) isolated from the heartwood of Auxemma oncocalyx Taub. The major constituent of QF, which represented around 80% of this fraction, was a terpenoid quinone named oncocalyxone A (1). Results show that QF (10 and 30 mg/kg body wt., i.p.) significantly inhibited paw edema induced by carrageenan at the second, third, and fourth hours. The effect was dose-dependent and long lasting, and QF was less effective orally. An antiedematogenic effect was also demonstrated in the dextran-induced paw edema. In this model, however, QF was somewhat less potent. QF (1 and 5 mg/kg body wt., i.p.) inhibited acetic acid-induced abdominal contractions in mice in a dose-dependent manner. In addition, QF (5 and 10 mg/kg body wt., i.p.) inhibited only the second phase (inflammatory) in the formalin test, and showed no effect in the hot-plate test in mice. The antinociceptive activity of QF was predominantly peripheral and independent of the opioid system. The observed effects of QF are, at least in part, probably due to the presence of oncocalyxone A (1). 相似文献
87.
This work is based on a survey of small mammals carried out in the Chapada dos Veadeiros National Park, a natural reserve located in the mountains of the Planalto Central Goiano in the Cerrado of Central Brazil. The 227 specimens collected represented six marsupial and 13 rodent species. Taxonomic, karyologic, and ecologic considerations are present and discussed in the present work. Our data reflected the faunal heterogeneity with respect to both elevation and vegetation because only eight of the 19 species were collected at both high and low elevations. The composition of the small mammal fauna of the park is influenced by predominance of forest formations at low elevations and cerrado with rupestrian areas at high elevations. Presence of endemic species and one undescribed demonstrated that the cerrado has an endemic fauna and a little known diversity of small mammals. 相似文献
88.
89.
Glucose Metabolism and Kinetics of Phosphorus Removal by the Fermentative Bacterium Microlunatus phosphovorus 总被引:3,自引:0,他引:3
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Margarida M. Santos Paulo C. Lemos Maria A. M. Reis Helena Santos 《Applied microbiology》1999,65(9):3920-3928
Phosphorus and carbon metabolism in Microlunatus phosphovorus was investigated by using a batch reactor to study the kinetics of uptake and release of extracellular compounds, in combination with 31P and 13C nuclear magnetic resonance (NMR) to characterize intracellular pools and to trace the fate of carbon substrates through the anaerobic and aerobic cycles. The organism was subjected to repetitive anaerobic and aerobic cycles to induce phosphorus release and uptake in a sequencial batch reactor; an ultrafiltration membrane module was required since cell suspensions did not sediment. M. phosphovorus fermented glucose to acetate via an Embden-Meyerhof pathway but was unable to grow under anaerobic conditions. A remarkable time shift was observed between the uptake of glucose and excretion of acetate, resulting in an intracellular accumulation of acetate. The acetate produced was oxidized in the subsequent aerobic stage. Very high phosphorus release and uptake rates were measured, 3.34 mmol g of cell−1 h−1 and 1.56 mmol g of cell−1 h−1, respectively, values only comparable with those determined in activated sludge. In the aerobic period, growth was strictly dependent on the availability of external phosphate. Natural abundance 13C NMR showed the presence of reserves of glutamate and trehalose in cell suspensions. Unexpectedly, [1-13C]glucose was not significantly channeled to the synthesis of internal reserves in the anaerobic phase, and acetate was not during the aerobic stage, although the glutamate pool became labeled via the exchange with intermediates of the tricarboxylic acid cycle at the level of glutamate dehydrogenase. The intracellular pool of glutamate increased under anaerobic conditions and decreased during the aerobic period. The contribution of M. phosphovorus for phosphorus removal in wastewater treatment plants is discussed on the basis of the metabolic features disclosed by this study. 相似文献