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61.
Soil-borne cereal mosaic virus (SBCMV) causes a severe disease in susceptible cultivars of winter wheat. The virus is vectored by the soil-borne protist Polymyxa graminis. Experiments were conducted to investigate whether SBCMV RNA2 could persist in seed from SBCMV-infected susceptible cultivars of winter wheat. Over 7,000 seedlings were generated from seed collected from two cultivars of SBCMV-infected winter wheat. Seedlings were grown in a glasshouse compartment and batch tested for the presence of SBCMV using real-time RT-PCR. The majority of batches tested positive for SBCMV, indicating an RNA2 transmission rate of 1.8–9.4% in wheat. The presence of the virus was confirmed by amplifying and sequencing a larger (400 bp) fragment of viral RNA2 in a sub-set of the seedlings testing positive by real-time RT-PCR. Root extracts from this sub-set tested negative for P. graminis using real-time PCR. The implications for disease epidemiology of this virus are discussed. The authors are British Civil Servants and as such their work is subject to British Crown Copyright. This means the exclusive copyright for the article cannot be transferred.  相似文献   
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63.
In Brassicaceae crop breeding programs, wild relatives have been evaluated as genetic resources to develop new cultivars with biotic and abiotic stress resistance. This has become necessary because of the diversification of ecotypes of diseases and pests, changing food preferences, advances in production technology, the use of new approaches such as in vitro breeding programs, and the need for economical production of F1 seed. To produce potential new cultivars, interspecific and intergeneric hybridizations have been performed between cultivated species and between cultivated species and their wild relatives. Furthermore, interspecific and intergeneric hybrids have been successfully produced using embryo rescue techniques. In this paper, we review the interspecific and intergeneric incompatibilities between Brassicaceae crops and their wild relatives, and the production, characterization, and improvement of synthetic amphidiploid lines, alien gene introgression lines, alloplasmic lines, monosomic alien chromosome addition lines, and monosomic alien chromosome substitution lines. The goal is to provide useful materials to support practical breeding strategies and to study the genetic effects of individual chromosomes on plant traits, the number of genes that control a trait, their linkage relationships, and genetic improvement in Brassicaceae crops.  相似文献   
64.
This study was conducted to investigate cytotoxic effect, phenolic content, DPPH, ABTS radical scavenging rate and nitrite scavenging rate from different solvent fractions of Codonopsis lanceolate root. At all extracts concentration, the cytotoxic effect on different fractions against human cancer cells was higher in n-hexane and butyl alcohol fractions than in the other fractions. The IC50 value on HeLa cell showed the lowest by 62.70 μg.mL-1 on n-hexane fraction, and exhibited the values of butyl alcohol fraction 341.36 μg.mL-1, methylene chloride 598.33 μg.mL-1, ethyl acetate fraction 860.44 μg.mL-1, DW fraction 2896.82 μg.mL-1. Total polyphenol content on different solvent fractions varied from 102.43 to 153.52 mg.g-1, and that of ethyl acetate fraction showed the highest amount. The DPPH and ABTS radical scavenging activity showed that the increase was proportional to the concentration, and the scavenging activity also showed the highest in ethyl acetate fraction. The nitrite scavenging activity of each fraction at pH 1.2 was in the order of EA > BA > MC > n-H > DW, and the lower the acidity, the higher nitrite scavenging activity, and there was no distinct detection of nitrite scavenging effects of the pH range 6.0. The results of this study suggested that the extract of Codonopsis lanceolate root may assist in the potential biological activities, and it was found that the activity was different depending on the organic solvent fraction and the water fraction.  相似文献   
65.
We evaluated the proximate composition, free sugar content, fatty acid composition, carotenoid content, total phenol content, and radical scavenging activity of the grain from various Korean maize hybrid cultivars grown in two different cropping seasons. The moisture, crude ash, crude fat, crude protein, total starch, and amylose contents were significantly higher in most of the maize hybrid cultivars when grown in the early-season than when grown in the late-season. The free sugar content, fatty acid composition, carotenoid content, and total phenol content differed significantly between cultivars and cropping seasons. The highest unsaturated fatty acid compositions of maize hybrids of early-season and late-season were 86.05 and 86.29%, respectively, in the Daanok cultivar. The carotenoid contents were significantly higher in maize hybrids of late-season compared to those of early-season. The highest total phenol content was 108.09 mg/100 g in Singwangok of the late-season. The radical scavenging activity of maize hybrids differed significantly between cultivars and cropping seasons.  相似文献   
66.
Understanding the molecular details of CO(2)-sorbent interactions is critical for the design of better carbon-capture systems. Here we report crystallographic resolution of CO(2) molecules and their binding domains in a metal-organic framework functionalized with amine groups. Accompanying computational studies that modeled the gas sorption isotherms, high heat of adsorption, and CO(2) lattice positions showed high agreement on all three fronts. The modeling apportioned specific binding interactions for each CO(2) molecule, including substantial cooperative binding effects among the guest molecules. The validation of the capacity of such simulations to accurately model molecular-scale binding bodes well for the theory-aided development of amine-based CO(2) sorbents. The analysis shows that the combination of appropriate pore size, strongly interacting amine functional groups, and the cooperative binding of CO(2) guest molecules is responsible for the low-pressure binding and large uptake of CO(2) in this sorbent material.  相似文献   
67.
Micropigs are the most likely source animals for xenotransplantation. However, an appropriate method for evaluating the lung of micropigs had not been established. Therefore, this study was performed to evaluate the feasibility of 64-channel multi-detector row computed tomography (MDCT) to measure the diameter of the pulmonary arteries and the lung volume in micropigs. The mean diameters of the trachea, and left and right bronchi were 1.6 ± 0.17, 1.18 ± 0.14, and 1.1 ± 0.11 cm, respectively. The mean diameters of the main, right, and left pulmonary arteries were 1.38 ± 0.09, 1.07 ± 0.26, and 0.98 ± 0.13 cm and the diameters of right, left, and common inferior pulmonary veins were 0.97 ± 0.20, 0.76 ± 0.20, and 1.99 ± 0.26 cm, respectively. The mean lung volume was 820.3 ± 77.11 mL. The data presented in this study suggest that the MDCT may be a noninvasive, rapid, and accurate investigational method for pulmonary anatomy in living lung donors.  相似文献   
68.
In this study fusaricidin, a cyclic depsipeptide isolated from Paenibacillus polymyxa E681 (E681), was demonstrated to control Phytophthora blight infection caused by Phytophthora capsici in red-pepper. The minimal inhibitory concentration (MIC) of fusaricidin was found to be 16 ppm against P. capsici. The disease severity of P. capsici was 40% at 0.1 ppm of fusaricidin when compared with water-treated control (81.7%) on post-treatment, whereas the disease severities on pre-treatment were 45% and 83.3% in fusaricidin (0.1 ppm) and water-treated control, respectively, in red-pepper plants. Significant (P?<?0.05) disease suppression was observed on treatment with fusaricidin (0.1 ppm) by foliar spray and soil drench. The disease severity was drastically reduced to 3.3% by soil drench of fusaricidin (1.0 ppm), whereas in water-treated control, the disease severity was 83.3% in the first experiment. Fusaricidin at 0.1 ppm reduced disease severity of P. capsici to 27.5% when compared with positive control (43.1%) and water-treated control (66.2%) in the second experiment. Soft rot disease in tobacco was suppressed upon treatment with fusaricidin at 1.0 ppm by leaf infiltration. RT-PCR analyses of Arabidopsis thaliana revealed that there was an up-regulation of pathogenesis-related (PR) gene expression in wild type A. thaliana (Col-0), while there was no accumulation of PR genes, which implies that the mechanism of protection might be based on a salicylic acid-dependent pathway. This is the first report that fusaricidin exhibits protection against plant pathogens in addition to activity as an antibiotic agent. Hence, E681 can play a role in plant protection by secretion of ISR elicitors including fusaricidin.  相似文献   
69.
Rubusoside (R) is a natural sweetener and a solubilizing agent with antiangiogenic and antiallergic properties. However, currently, its production is quite expensive, and therefore, we have investigated nine commercially available glycosidases to optimize an economically viable R-production method. A stevioside (ST)-specific β-glucosidase (SSGase) was selected and purified 7-fold from Aspergillus aculeatus Viscozyme L by a two-step column chromatography procedure. The 79 kDa protein was stable from pH 3.0 to pH 7.0 at 50-60 °C. Hydrolysis of ST by SSGase produced R and steviol monoglucosyl ester as determined by (1)H and (13)C nuclear magnetic resonance (NMR). Importantly, SSGase showed higher activity toward ST than other β-linked glucobioses. The optimal conditions for R production were 280 mM ST and 16.6 μL of SSGase at pH 5.1 and 63 °C. This is the first discussion detailing the production of R by enzymatic hydrolysis of ST and is useful for the food additive and pharmaceutical industries.  相似文献   
70.
We profiled and quantified glucosinolates, anthocyanins, carotenoids, and other secondary metabolites in the skin and flesh of pale green and purple kohlrabis. Analysis of these distinct kohlrabis revealed the presence of 8 glucosinolates, 12 anthocyanins, 2 carotenoids, and 7 phenylpropanoids. Glucosinolate contents varied among the different parts and types of kohlrabi. Glucoerucin contents were 4-fold higher in the flesh of purple kohlrabi than those in the skin. Among the 12 anthocyanins, cyanidin 3-(feruloyl)(sinapoyl) diglucoside-5-glucoside levels were the highest. Carotenoid levels were much higher in the skins than the flesh of both types of kohlrabi. The levels of most phenylpropanoids were higher in purple kohlrabi than in pale green ones. trans-Cinnamic acid content was 12.7-fold higher in the flesh of purple kohlrabi than that in the pale green ones. Thus, the amounts of glucosinolates, anthocyanins, carotenoids, and phenylpropanoids varied widely, and the variations in these compounds between the two types of kohlrabi were significant.  相似文献   
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