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161.
Wagner de Souza Tavares Ivan Cruz Fernando Petacci Sebastio Loureno de Assis Júnior Silvia de Sousa Freitas Jos Cola Zanuncio Jos Eduardo Serro 《Industrial Crops and Products》2009,30(3):384-388
Extracts of 12 Asteraceae were tested on Spodoptera frugiperda (Lepidoptera: Noctuidae) and on their parasitoids Telenomus remus (Hymenoptera: Scelionidae) and Trichogramma pretiosum (Hymenoptera: Trichogrammatidae). The plants Lychnophora ericoides and Trichogonia villosa were toxic for 97.7 ± 0.15% of one-day-old eggs of S. frugiperda and Lepidaploa lilacina for 72.0 ± 2.50% for two-day-old eggs of this insect. Extracts of Vernonia holosenicea, Lychnophora ramosissima and Chromolaena chaseae had higher impact on S. frugiperda, while those of Eremanthus elaeagnus and L. ericoides were more selective to T. pretiosum and T. remus. Asteraceae extracts present potential for integrated pest management programs of S. frugiperda. 相似文献
162.
163.
Wagner Mateus Costa Melo Marcio Balestre Renzo Garcia Von Pinho Júlio Sílvio de Sousa Bueno Filho 《Euphytica》2014,195(3):331-344
This study seeks to quantify the importance of epistatic effects on the heterosis of maize using complex pedigrees in a single model of the so-called bi-, tri-, and tetra-alleles in an analysis with and without information from microsatellite markers. To this end, 51 inbred lines were sampled from different backgrounds, obtaining 6 double cross hybrids, 14 triple cross hybrids, and 58 single cross hybrids, for a total of 78 hybrids. Seventy-nine microsatellite markers were used in the genotyping of the 51 lines. These markers were distributed throughout the 10 linkage groups in maize. This information was used to construct an information matrix on kinship. The mixed models and restricted maximum likelihood approaches were used to estimate additive, dominant and epistatic effects. It was observed that the dominant by dominant epistasis was the most important effect related to genetic control of the heterosis in maize. Also, our study demonstrated that it is possible to exploit a large amount of information when we jointly analyze simple, double, and three-way cross hybrids under the same model. Using this approach, it is possible to dissect heterosis into several components and to adopt the best crossbreeding strategy based on the importance of each component. Additionally, it was possible to verify that the use of molecular markers improves the accuracy of calculating the epistatic and dominance effects. Thus, using the current state-of-art in quantitative genetics and statistical methods the concept of crossbreeding can be expanded to frontiers that are far beyond the traditional general and specific combining ability. 相似文献
164.
D Loddo E Sousa R Masin I M Calha G Zanin C Fernández‐Quintanilla J Dorado 《Weed Research》2014,54(4):356-365
Studies on weed germination are required to develop efficient integrated weed management strategies that should be transferable at wide scale and accurate at local level. To study interpopulation variability, which may hamper this process, three local populations of Datura stramonium were collected in Italy, Portugal and Spain and then cultivated simultaneously in three common gardens under different environmental conditions. Hence, nine seed lots were included in the germination tests performed at a range of constant incubating temperatures. Significant effects of population of origin, cultivation site, incubating temperature and their interaction were detected on mean germination percentage and germination t50. Mean germination percentage varied from 0.0 to 89.7% ± 2.10 SE at 8 and 20°C respectively. Mean germination t50 ranged from 636.1 ± 24.86 SE to 267.0 ± 16.06 SE hours at 12 and 20°C respectively. Seed lots deriving from the Portuguese population presented the lowest germination percentages and highest germination t50 at low incubating temperatures, regardless of the cultivation site. This behaviour could be related to an adaptive process of the Portuguese population to the local environmental conditions, produced by the combination of climate and agronomic management. The presence of high interpopulation variability for D. stramonium could hinder the development of transferable IWM strategies. However, management plans could be proposed at regional scale according to the approach of modifying the patterns of agronomic disturbances to which the local populations have adapted. 相似文献
165.
Environmental factors at different spatial scales governing soil fauna community patterns in fragmented forests 总被引:1,自引:0,他引:1
Pedro Martins da Silva Matty P. Berg Artur R. M. Serrano Florence Dubs José Paulo Sousa 《Landscape Ecology》2012,27(9):1337-1349
Spatial and temporal changes in community structure of soil organisms may result from a myriad of processes operating at a hierarchy of spatial scales, from small-scale habitat conditions to species movements among patches and large-sale landscape features. To disentangle the relative importance of spatial and environmental factors at different scales (plot, patch and landscape), we analyzed changes in Collembola community structure along a gradient of forest fragmentation, testing predictions of the Hierarchical Patch Dynamics Paradigm (HPDP) in different European biogeographic regions (Boreal, Continental, Atlantic, Mediterranean, Alpine). Using variance partitioning methods, based on partial CCAs, we observed that the independent effect of environmental processes was significantly explaining Collembola community variance in all regions, while the relative effect of spatial variables was not significant, due to the observed high levels of landscape heterogeneity along the gradient. Environmental factors at the patch and plot scales were generally significant and explained the larger part of community changes. Landscape variables were not significant across all study sites. Yet, at the landscape level, an increase in forest habitat and proximity of forest patches were showed to have an indirect influence on local community changes, by influencing microhabitat heterogeneity at lower spatial scales in all studied regions. In line with HPDP, large-scale landscape features influenced spatio-temporal changes in soil fauna communities by constraining small-scale environmental processes. In turn, these provided mechanistic understanding for diversity patterns operating at the patch scale, via shifts in community weighted mean of Collembola life-forms occurring in local communities along the fragmentation gradient. 相似文献
166.
Maria Izabel Gomes Silva Maria Anglica Gomes Silva Manuel Rufino de Aquino Neto Brinell Arcanjo Moura Helenira Loureno de Sousa Everton Paulo Homem de Lavor Patrícia Freire de Vasconcelos Danielle Silveira Macêdo Damio Pergentino de Sousa Silvnia Maria Mendes Vasconcelos Francisca Cla Floreno de Sousa 《Fitoterapia》2009,80(8):506-513
The present study investigated the effects of isopulegol, a monoterpene alcohol, in PTZ-induced convulsions and verified possible involved mechanisms. Saline, isopulegol or diazepam were intraperitonealy injected 30 min before PTZ. The latency for development of convulsions and mortality, as well as the mortality protection percentage was recorded. For investigating the involvement of GABAergic system, flumazenil was utilized. The activity of antioxidant enzyme catalase as well as the levels of reduced glutathione and lipid peroxidation were measured in brain hippocampus. Similarly to diazepam, isopulegol significantly prolonged the latency for convulsions and mortality of mice. All animals were protected against mortality at higher dose of isopulegol. Flumazenil pretreatment decreased the prolongation of seizure latency induced by both diazepam and isopulegol, although it was not able to reverse the latency and protection percent for mortality. Isopulegol also significantly prevented PTZ-induced increase in lipid peroxidation, preserved catalase activity in normal levels, and prevented the PTZ-induced loss of GSH in hippocampus of mice. These results suggest that the anticonvulsant and bioprotective effects of isopulegol against PTZ-induced convulsions are possibly related to positive modulation of benzodiazepine-sensitive GABAA receptors and to antioxidant properties. 相似文献
167.
Marta Salvador Ferreira Diana I. S. P. Resende Jos M. Sousa Lobo Emília Sousa Isabel F. Almeida 《Marine drugs》2021,19(8)
Marine ingredients are a source of new chemical entities with biological action, which is the reason why they have gained relevance in the cosmetic industry. The facial care category is the most relevant in this industry, and within it, the sensitive skin segment occupies a prominent position. This work analyzed the use of marine ingredients in 88 facial cosmetics for sensitive skin from multinational brands, as well as their composition and the scientific evidence that supports their efficacy. Marine ingredients were used in 27% of the cosmetic products for sensitive skin and included the species Laminaria ochroleuca, Ascophyllum nodosum (brown macroalgae), Asparagopsis armata (red macroalgae), and Chlorella vulgaris (microalgae). Carotenoids, polysaccharides, and lipids are the chemical classes highlighted in these preparations. Two ingredients, namely the Ascophyllum nodosum extract and Asparagopsis armata extracts, present clinical evidence supporting their use for sensitive skin. Overall, marine ingredients used in cosmetics for sensitive skin are proposed to reduce skin inflammation and improve the barrier function. Marine-derived preparations constitute promising active ingredients for sensitive skin cosmetic products. Their in-depth study, focusing on the extracted metabolites, randomized placebo-controlled studies including volunteers with sensitive skin, and the use of extraction methods that are more profitable may provide a great opportunity for the cosmetic industry. 相似文献
168.
Andre Freire Cruz Lucas Fagundes Silva Tiago Vieira Sousa Alessandro Nicoli Trazilbo Jose de Paula Junior Eveline Teixeira Caixeta Laercio Zambolim 《European journal of plant pathology / European Foundation for Plant Pathology》2018,152(2):343-354
The common bean (Phaseolus vulgaris L.) is widely cultivated in Brazil and is known as a very important crop for families in this country. Fusarium wilt severely harms common beans and has become a big issue for this crop. In order to assist the breeding programs that target resistance to this disease, the evaluation of genetic diversity of the pathogen and its molecular characterization are crucial. Thus, the present goal was to identify Fusarium isolates obtained from several places in Brazil using molecular tools; select molecular markers for these isolates; and analyze their diversity. All of isolates were molecularly identified as Fusarium oxysporum f. sp. phaseoli (Fop). By using seven selected SSR markers, the results of diversity obtained by the dendrogram and the Bayesian analysis formed four groups where a large diversity of this fungus was found within each state. However, the groups were more homogenous according to the collection source and the pathogenicity test. More specifically, group 2 was composed of the most virulent strains and originated from Minas Gerais State – UFV, and group 3 was mostly composed by isolates from Goias state. Group I was also more diverse in terms of location and virulence. The overall results indicated a positive correlation between Fusarium diversity and its virulence to common bean. Furthermore, the use of these markers was effective in molecular identification and in detecting polymorphism within F. oxysporum f. sp. phaseoli. 相似文献
169.
Carla Verônica Corrêa Aline Mendes de Sousa Gouveia Bruno Novaes Menezes Martins Natália de Brito Lima Lanna Ana Emília Barbosa Tavares Veridiana Zocoler Mendonça 《Journal of plant nutrition》2018,41(10):1345-1350
The current study aimed to evaluate the effect of top-dressed potassium (K) application on the production of hybrid cucumber “Sapphire.” The experimental design was a randomized complete block, with five blocks of 0.80 × 0.40 m2 each and eight replicate plants per block. The five fertilization rates of K used were 0, 45, 90, 135, and 180 kg K2O ha?1. Data collection consisted of the estimation of fruit diameter, fruits length, fruit fresh and dry weights, the number of fruits per plant, and the weight of fruits per plant. The number of fruits per hectare and the fruit fresh weight per hectare were calculated. Fruit tissue was analyzed for determination of macronutrient concentrations, pH, titratable acidity, soluble solids, sugar contents, and protein content. The data were statistically analyzed using regression analysis and analysis of variance (ANOVA). There was a significant effect of the fertilization rate of K on fruit diameter, fruit fresh and dry weights, macronutrients concentrations in fruits, titratable acidity, soluble solids, and reducing sugars. A quadratic equation was adjusted for the number of fruits per plant and per hectare; fruit yield per plant and per hectare, with maximum top-dressing doses, was estimated to be between 60 and 95 kg K2O ha?1. A linear increase was obtained in the pH. An increase in the K fertilization rate caused a linear decrease in the fruit length. 相似文献
170.
Effects of beta‐glucans ingestion (Saccharomyces cerevisiae) on metabolism of rats receiving high‐fat diet
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T. V. de Araújo E. F. Andrade R. V. Lobato D. R. Orlando N. F. Gomes R. V. de Sousa M. G. Zangeronimo L. J. Pereira 《Journal of animal physiology and animal nutrition》2017,101(2):349-358
We investigated the effects of beta‐glucans (Saccharomyces cerevisiae) ingestion on metabolic parameters of Wistar rats receiving high‐fat diet. The experimental period was divided into two stages: in the first one, the animals were divided into two groups containing 12 animals each. The first group received commercial feed and the second received high‐fat diet containing 20% of pork fat during 60 days. At the end of this period, body weight, blood glucose and Lee index were assessed. In the second stage, those 24 animals were redivided into four groups: (C) – control diet; (CB) – control diet and treated with Beta‐glucan (BG); (O) – obese animals and (OB) – obese animals treated with BG. Animals from groups CB and OB received 30 mg/kg of BG dissolved in saline solution by gavage. Animals from groups C and O received only saline solution for 28 days. The design used was totally randomized in 2 × 2 factorial scheme. Data were submitted to analysis of variance (anova ). Animals from OB group showed inferior levels (p < 0.05) of total cholesterol (13.33%), triacylglycerols (16.77%) and blood glucose (23.97%) when compared to the animals from group O. The use of BG has provided smaller increase in Lee index (p < 0.05), without promoting alteration in feed and water consumption, organs weight, HDL‐C, LDL+VLDL‐C, carcass composition, villus/crypt ratio, and pancreas, kidney and stomach histology. BG from S. cerevisiae promoted beneficial metabolic effects in rats receiving high‐fat diet. 相似文献