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51.
Antonio Carlos Martins dos Santos Kleycianne Ribeiro Marques Larissa Urzêdo Rodrigues Álvaro José Gomes de Faria Vitor L. Nascimento 《Journal of plant nutrition》2013,36(19):2522-2531
AbstractBiofortification of soybean grains with lithium (Li) is a strategy to improve a food with high social acceptance, in order to promote health benefits. The aim of this work was to evaluate the development of plants and the production of biofortified soybeans with two Li sources. The experiment was conducted in a completely randomized design with five replicates. Ten treatments were obtained in a 2x5 factorial scheme, comprising two sources of Li (LiOH - Li hydroxide and Li2SO4 - Li sulfate) and five doses (0, 30, 60, 90 and 120?mg kg?1) in stages V4 and R1. The supply of Li promoted significant effects (p?≤?0.05) on the morphology, yield components and nutritional status of soybean plants. The highest grain yield was obtained with the use of Li2SO4 at the estimated dose of 45.7?mg kg?1. The plants accumulated Li between 8.00 and 11.20?mg kg ?1, respectively, with the use of Li2SO4 and LiOH. In the grains, the highest concentrations of Li were obtained with the application of 120?mg kg?1. Li2SO4 and LiOH are good sources for biofortification of soybean grains. 相似文献
52.
Neospora caninum is a protozoon that causes abortion in cattle and neuromuscular lesions in dogs, with the formation of cysts mainly in the central nervous system. Since N. caninum is an intracellular parasite with tropism for the cells of nervous system, this study evaluated the respiratory metabolism of glial cells infected by this* parasite. Glial cultures obtained from the cerebral cortex of newborn rats were kept in DMEM enriched with 10% fetal bovine serum, 1 mM pyruvic acid and 2 mM of L-glutamine. They were infected at a ratio of approximately 1:1 (cell/parasite). Oxygen consumption was evaluated by polarography in the non infected and N. caninum infected groups, 24 and 72 h following infection. Glial cell respiration after 24 and 72 h was 307.2 +/- 34.7 and 308.9 +/- 64.1 microL of oxygen per mug of total protein per minute, and 566.2 +/- 54.6 and 579 +/- 117.5 microL O2/microg of total protein/minute in the control and infected groups, respectively. These results show that N. caninum does not interfere with glial respiration in vitro. 相似文献
53.
M. Ângelo Rodrigues Sandra Afonso Isabel Q. Ferreira Margarida Arrobas 《Archives of Agronomy and Soil Science》2017,63(5):626-637
The adaptation of stevia to the growing conditions of NE Portugal is assessed, including the tolerance of this species to cold temperatures, and the potential to produce biomass when grown as an annual crop and when subjected to various nitrogen (N) rates and two harvesting regimes. Almost all the plants died during the winter of 2014 (minimum temperatures peaked at ?8.0°C), making it necessary to replant the crop the following spring. With the best cutting regime (double cut) and N rate (150 kg N ha?1), 1514.4 and 2390.0 kg ha?1 of dry leaves were produced, respectively, in 2014 and 2015. Leaf chlorophyll concentrations estimated by the SPAD (Soil and Plant Analysis Development)-502 chlorophyll meter and a NDVI (Normalized Difference Vegetation Index) carried out by the Field Scout CM 1000 spectroradiometer showed significant differences among N rates, proving to be good indicators of plant N nutritional status. Based on the leaf analysis, provisional sufficiency ranges for N are proposed, namely 25–35 g kg?1 for mid-summer and 15–25 g kg?1 for early autumn. The fluorescence of chlorophyll a and the transient fluorescence intensity performed by the OS-30p+ fluorometer failed to show any stress induced by no-N control treatments in comparison to N-treated plants. 相似文献
54.
Isabelle Boulogne Reginaldo Constantino Nadine Amusant Michaël Falkowski Alice M. S. Rodrigues Emeline Houël 《Journal of pest science》2017,90(1):19-37
The genus Nasutitermes is among the most abundant wood-feeding Termitidae and an extremely diverse and heterogeneous group in terms of its biogeography and morphology. Despite the major role of several Nasutitermes species as structural pests, the phylogenetic status of this genus is still unclear, along with a confused taxonomy and species identification remaining difficult. The first aim of this review was thus to gather and discuss studies concerning the taxonomic status of the genus Nasutitermes in order to clarify this crucial point. Then, our goal was to gain new insights into the management of N. corniger, considered to be the most economically detrimental pest of this genus in South America and a Nasutitermes model species, while filtering available information concerning its biology through the prism of termite control, as well as critically examine the existing methods. We indeed strongly believe that increasing our knowledge of this species’ biological strategies is the key to progress in the challenging question of their sustainable management. 相似文献
55.
Ciro Abbud Righi Otávio Camargo Campoe Marcos Silveira Bernardes Aureny Maria Pereira Lunz Sônia Maria Stefano Piedade Carlos Rodrigues Pereira 《Agroforestry Systems》2013,87(6):1351-1362
The coffee leaf-miner (CLM) (Leucoptera coffeella Guérin-Mèneville; Lepidoptera: Lyonetiidae), the main pest of coffee plants, occurs widely throughout the Neotropics where it has a significant, negative economic and quantitative impact on coffee production. This study was conducted in a rubber tree/coffee plant interface that was influenced by the trees to a varying degrees depending on the location of the coffee plants, i.e. from beneath the rubber trees, extending through a range of distances from the edge of the tree plantation to end in a coffee monocrop field. The most severe damage inflicted on coffee plants by the CLM (number of mined leaves) from April, which marks the start of the water deficit period, until September 2003 was in the zone close to the rubber trees, whereas the damage inflicted on plants in the monocropped field was comparable to that on coffee plants grown directly beneath the rubber trees, which received about 25–40 % of the available irradiance (Ir—available irradiation at a certain position divided by the irradiation received in full sunlight, i.e. in the monocrop). From May until July damage caused by the CLM nearly doubled in each month. In midwinter (July), the damage decreased perceptibly from the tree edge toward the open field. From September onward, with the rising air temperatures CLM damage in the coffee monocrop started to increase. Based on these results, we conclude that coffee plants grown in the full sun incurred the most damage only at the end of winter, with warming air temperatures. Coffee plants grown in shadier locations (25–40 % Ir) were less damaged by the CLM, although a higher proportion of their leaves were mined. The rubber trees probably acted as a shelter during the cold autumn and winter seasons, leading to greater CLM damage over a distance outside the rubber tree plantation that was about equal to the height of the trees. Future studies should attempt to relate leaf hydric potential to pest attack in field conditions. More rigorous measurements of shade conditions could improve our understanding of the relationship of this factor to CLM attack. 相似文献
56.
Alice Cristina Rodrigues Andreza Viana Neri Arshad Ali Pedro Manuel Villa Walnir Ferreira-Júnior 《林业研究》2020,31(5):1599-1611
Evaluating the influences of fine-scale habitat heterogeneity on the composition, diversity, structure and functioning of forests is critical to understand how tropical forests will respond to climate change and devise forest management strategies that will enhance biodiversity conservation and aboveground biomass stock. Here, we hypothesized that topographic and soil factors determine fine-scale habitat differentiation, which in turn shape community composition, species richness, structure and aboveground biomass at the local scale in tropical forests.To test this hypothesis, we selected two areas(each100 × 100 m) with contrasting fine-scale topographic conditions where all trees, palms and lianas with a diameter at breast height ≥ 10 cm were tagged and identified to species. In each selected area, 100 subplots of 10 × 10 m were established. We mainly found that higher topographic variability caused higher habitat differentiation with changes in species composition and community structure,but did not change species richness. Our habitat-scale analyses indicated that, in the less heterogeneous area, the distribution of species was more uniform along a fine-scale topographical gradient with no variation in convexity,which induced changes in structure and aboveground biomass, but not in species richness. The nonsignificant relationship between species richness and aboveground biomass may be attributable to species redundancy or functional dominance. This study suggests that environmental filtering is a fundamental process for shaping community assembly and forest functioning along a local topographical gradient in tropical forests. 相似文献
57.
Joadil G. Abreu Víctor M. Fernández-Cabanás Janderson A. Rodrigues Matheus Abreu Eduardo A. Ferreira Wender M. Peixoto 《Grassland Science》2023,69(1):33-41
The methods used to evaluate kinetic parameters of ruminant feeds can be in situ and in vitro. For both methods, it is necessary to maintain cannulated animals in order to collect the inoculum from the rumen, which has been under strong pressure from society, in terms of animal welfare policies, to avoid this type of practices. This work aimed to evaluate the estimation of in vitro digestibility and fermentation of elephant grass forage by near infrared reflectance spectroscopy (NIRS), as a fast and noninvasive alternative to the in vitro method. The experimental design was in randomized blocks with three repetitions. The treatments were arranged in a split-plot scheme, with 13 genotypes in the plot and 15 regrowth ages in the subplot. Crude protein (CP) and neutral detergent fiber (NDF) contents; in vitro dry matter (IVDMD) and NDF (IVNDFD) digestibilities; and total volume (Vt), gas production rate (μ) and half-life conventional analyses were determined for pre-dried elephant grass forage samples. For the evaluation of NIRS models performance, coefficient of determination (R2cv) and standard error of cross validation (SECV) were used. As the regrowth age advanced, there was a linear increase in the NDF content and a linear reduction in the IVDMD, IVNDFD and Vt values. The NIRS estimates proved to be adequate for IVDMD (R2cv = .95), IVNDFD (R2cv = .85), Vt (R2cv = .81) and gas production at 48 (R2cv = .82), 72 (R2cv = .85) and 96 h (R2cv = .84), confirming as an alternative to the in vitro methods that dispense with the use of cannulated animals. 相似文献
58.
由于霉菌毒素是一类无色无臭无味的物质,所以测定饲料原料和饲料成品以监测霉菌毒素的污染是非常重要的. 霉菌毒素这一术语源自希腊语单词mycos和toxikon,是指在各种各样环境条件下由真菌产生的次生有毒代谢产物. 相似文献
59.
Jorge Miguel Silva Faria Inês Sena Bruno Ribeiro Ana Margarida Rodrigues Carla Maria Nobre Maleita Isabel Abrantes Richard Bennett Manuel Mota Ana Cristina da Silva Figueiredo 《Journal of pest science》2016,89(1):207-217
The Columbia root-knot nematode (CRKN), Meloidogyne chitwoodi, is an EPPO A2 type quarantine pest since 1998. This nematode causes severe damage in economically important crops such as potato and tomato, making agricultural products unacceptable for the fresh market and food processing. Commonly used nematicidal synthetic chemicals are often environmentally unsafe. Essential oils (EOs) may constitute safer alternatives against RKN. EOs, isolated from 56 plant samples, were tested against CRKN hatching, in direct contact bioassays. Some of the most successful EOs were fractionated and the hydrocarbon molecules (HM) and oxygen-containing molecules (OCM) fractions tested separately. 24 EOs displayed very strong hatching inhibitions (≥90 %) at 2 µL mL?1 and were further tested at lower concentrations. Dysphaniaambrosioides, Filipendula ulmaria, Ruta graveolens, Satureja montana and Thymbra capitata EOs revealed the lowest EC50 values (<0.15 µL mL?1). The main compounds of these EOs, namely 2-undecanone, ascaridol, carvacrol, isoascaridol, methyl salicylate, p-cymene and/or γ-terpinene, were putatively considered responsible for CRKN hatching inhibition. S. montana and T. capitata OCM fractions showed hatching inhibitions higher than HM fractions. The comparison of EO and corresponding fractions EC50 values suggests interactions between OCM and HM fractions against CRKN hatching. These species EOs showed to be potential environmentally friendly CRKN hatching inhibitors; nonetheless, bioactivity should be considered globally, since its HM and OCM fractions may contribute, diversely, to the full anti-hatching activity. 相似文献
60.
F. P. Vilela M. R. Frazão D. P. Rodrigues R. G. Costa M. R. T. Casas S. A. Fernandes J. P. Falcão F. Campioni 《Zoonoses and public health》2018,65(1):e34-e43
Salmonella Dublin is strongly adapted to cattle causing enteritis and/or systemic disease with high rates of mortality. However, it can be sporadically isolated from humans, usually causing serious disease, especially in patients with underlying chronic diseases. The aim of this study was to molecularly type S. Dublin strains isolated from humans and animals in Brazil to verify the diversity of these strains as well as to ascertain possible differences between strains isolated from humans and animals. Moreover, the presence of the capsular antigen Vi and the plasmid profile was characterized in addition to the anti‐microbial resistance against 15 drugs. For this reason, 113 S. Dublin strains isolated between 1983 and 2016 from humans (83) and animals (30) in Brazil were typed by PFGE and MLVA. The presence of the capsular antigen Vi was verified by PCR, and the phenotypic expression of the capsular antigen was determined serologically. Also, a plasmid analysis for each strain was carried out. The strains studied were divided into 35 different PFGE types and 89 MLVA‐types with a similarity of ≥80% and ≥17.5%, respectively. The plasmid sizes found ranged from 2 to >150 kb and none of the strains studied presented the capsular antigen Vi. Resistance or intermediate resistance was found in 23 strains (20.3%) that were resistant to ampicillin, ciprofloxacin, chloramphenicol, imipenem, nalidixic acid, piperacillin, streptomycin and/or tetracycline. The majority of the S. Dublin strains studied and isolated over a 33‐year period may descend from a common subtype that has been contaminating humans and animals in Brazil and able to cause invasive disease even in the absence of the capsular antigen. The higher diversity of resistance phenotypes in human isolates, as compared with animal strains, may be a reflection of the different anti‐microbial treatments used to control S. Dublin infections in humans in Brazil. 相似文献