A recombinant modified vaccinia Ankara (MVA) virus expressing mature viral protein 2 (VP2) of the infectious bursal disease virus (IBDV) was constructed to develop MVA-based vaccines for poultry. We demonstrated that this recombinant virus was able to induce a specific immune response by observing the production of anti-IBDV-seroneutralizing antibodies in specific pathogen-free chickens. Besides, as the epitopes of VP2 responsible to induce IBDV-neutralizing antibodies are discontinuous, our results suggest that VP2 protein expressed from MVA-VP2 maintained the correct conformational structure. To our knowledge, this is the first report on the usefulness of MVA-based vectors for developing recombinant vaccines for poultry. 相似文献
Journal of Soils and Sediments - Sapropel is an organic-rich sediment formed under conditions that can result in sequestration of trace metals. Here, we determined the concentration of total... 相似文献
Boron (B) requirement and its interaction with liming for eucalyptus plantations in sandy soils of Brazilian Pampa are poorly understood. Aiming to diminish this gap, seedlings of Eucalyptus urograndis were grown in pots with Arenosol fertilized with B at rates 0.0, 1.0, 2.5, 5.0 and 10.0 mg B dm?3, with and without liming. Results of shoot and root dry matter and stem diameter did not evidence the necessity of B fertilization. With the exception of the 1.0 mg B dm?3+lime, all other B-fertilized treatments promoted visual symptoms of toxicity, which were partially mitigated by liming. Liming exacerbated the B loss by leaching, but after five months, limed soils had higher content of available B and their plants had higher B concentration in shoots and roots. For our conditions, application of ≥2.5 mg B dm?3 can cause serious toxic injuries to plants and enlarge dramatically the B losses leaching. 相似文献
Unlike maternal inheritance in sexual hybridization, plant somatic hybridization allows transfer, mixing and recombination of cytoplasmic genomes. In addition to the use of somatic hybridization in plant breeding programs, application of this unique tool should lead to a better understanding of the roles played by the chloroplastic and mitochondrial genomes in determining agronomically important traits. The nucleotide sequences of cytoplasmic genomes are much more conserved than those of nuclear genomes. Cytoplasmic DNA composition in somatic hybrids is commonly elucidated either by length polymorphism analysis of restricted genome regions amplified with universal primers (PCR-RF) or by hybridization of total DNA using universal cytoplasmic probes. In this study, we demonstrate that single-stranded conformational polymorphism (SSCP) analysis is a powerful, quick and easy alternative method for cytoplasmic DNA characterization of somatic hybrids, especially for mitochondrial DNA. The technique allows detection of polymorphisms based on both size and sequence of amplified targets. Twenty-two species of the subfamily Aurantioideae were analyzed with eight universal primers (four from chloroplastic and four from mitochondrial regions). Differences in chloroplastic DNA composition were scored in 98% of all possible two-parent combinations, and different mitochondrial DNA profiles were found in 87% of them. Analysis by SSCP was also successfully used to characterize somatic hybrids and cybrids obtained by fusion of Citrus sinensis (L.) Osb. and C. excelsa Wester protoplasts. 相似文献
A rapid and sensitive liquid chromatography/electrospray ionization/tandem mass spectrometry (LC-ESI-MS-MS) method has been developed for the determination of the plant growth regulator paclobutrazol in pear samples. Extraction was performed with methanol by using a high-speed blender Ultra-Turrax, and 10 microL of pear extract was directly injected in the LC-ESI-MS-MS system without any previous sample treatment. The highest sensitivity of the method was achieved under MS-MS conditions obtaining a limit of detection of 0.7 microg/kg and a quantification limit of 5 microg/kg, with a run time of only 5.5 min. Recoveries for paclobutrazol from spiked pear samples at 0.005, 0.05, and 0.5 mg/kg were around 82-102% with relative standard deviations between 2 and 7%. The method was applied to real treated and untreated samples of pears, using quality control samples as a evaluation of the method reliability. Two MS-MS transitions were selected, one for quantification (294 > 70) and the other for confirmation of the analyte (296 > 70). All the experiments were performed in compliance with good laboratory practices. 相似文献
Polyamines are considered as plant growth regulating compounds; among them, cadaverine has been correlated with root growth promotion or osmotic stress mitigation in some plant species. The purpose of this study was to evaluate the capacity of bacterial Azospirillum brasilense Az39 strain to produce cadaverine in chemically defined medium and inoculated plants, and to correlate this capacity with root growth promotion or osmotic stress mitigation in hydroponics conditions. To evaluate cadaverine production in chemically defined medium A. brasilense Az39 was cultivated aerobically at 30 °C and 80 rpm in NFb medium or NFb-l supplemented with the precursor l-lysine. To evaluate the bacterial cadaverine production and growth promotion in plants, rice (Oryza sativa L.) cv. El Paso 144 seedlings were inoculated and hydroponically cultured under optimal conditions in growth chamber. In both, cadaverine was identified and quantified by dansyl-derivative method using a fluorescence-HPLC system, and lysine decarboxylase (LDC) activity was determined by 14CO2 production in a closed tube system fed with [14C]-lysine. To evaluate the possible role of bacterial cadaverine in osmotic stress conditions, abscisic acid (ABA) production was analyzed in rice seedlings hydroponically cultured under 0 (no stress), ?0.47 (stress) or ?0.82 (severe stress) MPa osmotic potential generated by mannitol, with the addition of 1 nM or 1 μM cadaverine or A. brasilense Az39 inoculation. Our results indicate that A. brasilense Az39 promoted root growth and helped mitigate osmotic stress in rice seedlings, due in part to cadaverine production. 相似文献
Irrigation with reclaimed water and soil amendment with sewage sludge are becoming common practices in arid and semiarid areas. When wastewater treatments do not efficiently remove all the contaminants, these contaminants can later end up in agricultural soils. These contaminated soils are a potential source of surface and groundwater pollution by leaching and runoff. In the present work, we assessed the behavior of alcohol sulfates (AS) in agricultural soil. For the experimental work, a tract of soil was irrigated with linear alcohol sulfates with 12–18 hydrocarbon chain and subsequently tested for AS concentration from November 2014 to July 2015. The highest concentrations of AS were found at the top layer of soil (29.80 to 6.23 mg kg?1). The adsorption rate and the amount of surfactant adsorbed increased as the length of the hydrocarbon chain increases. AS homologues can leach up to 60 cm. A mathematical model was applied to predict the environmental behavior of AS in the agricultural soils studied. Disappearance rate constant (k) values for AS homologues were between ?5.10·10?3 and ?1.68·10?2 h?1, and average half-life values were between 37 and 135 h. Coefficients of determination (R2) between 92.4 and 99.1% showed that the proposed model satisfactorily describes the experimental results. The present study provides a conceptual framework and essential parameters for predicting and understanding the environmental behavior of AS in agricultural soils.
