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51.
Martin Kulhánek Jiří Balík Jindřich Černý Lucie Peklová Ondřej Sedlář 《Archives of Agronomy and Soil Science》2013,59(1):67-74
Precise field experiments were established on two sites with winter wheat under different soil-climatic conditions in the Czech Republic. Four treatments were fertilized with same dose of nitrogen (200 kg N ha?1) and increasing dose of sulphur (0, 10, 20 and 40 kg S ha?1) using nitrogen–sulphur (N–S) fertilizer with calcium sulphate form. Soil and plant aboveground biomass samples were taken in the stages of development BBCH 26–28; 30–32; 37–39; 49–51. The winter wheat grain yield ranged between 7.20 and 10.86 t ha?1 and had an increasing trend with increasing sulphur dose. Although the differences were usually not statistically significant, there were found increasing tendencies of bioavailable sulphur content in soil with increasing S split doses. Soil S content decreased with time probably due to plant uptake. Sulphur dose did not influence the S content in plant aboveground biomass. The total S contents in grain after harvest ranged between 0.09% and 0.14% and were not significantly influenced with the fertilizing treatment. The same statement is valid for the S content in straw, which ranged between 0.03% and 0.11%. Both, S content in winter wheat seeds and straw were strongly influenced by the site conditions. 相似文献
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Vulpia myuros is an annual grass species of Mediterranean origin, which has achieved a global distribution. It is a fast‐growing species, with high colonisation and competitive abilities. This species is considered an invasive weed in most countries where it has been introduced, with highly negative economic impact where it now dominates. It is increasingly found to be a problematic weed in winter cereals, especially in no‐till and reduced tillage systems, across Europe, United States and Australia. Seeds of V. myuros have reduced germination potential when buried. However, where tillage interventions are reduced, ideal conditions for V. myuros are created. Minimum and no tillage practices are increasing worldwide, with a concomitant increase in the spread and abundance of V. myuros. Effectiveness of herbicides is mostly suboptimal, in particular for well‐established populations forming dense swards, even though no herbicide resistance has yet been identified. An integrated management approach, increasing crop diversification combined with management adaptations, possibly including herbicides is suggested as an effective control strategy. Despite increasing research on V. myuros, more information is needed to optimise the management of this weed. Based on the species’ Mediterranean origins and adaptation to warm and dry environments, an increase of its global importance may be expected with climate changes. It is thus paramount to increase the awareness around this species, improve its identification in the field and monitor its spread before it becomes a concern of similar magnitude to grass weeds like Alopecurus myosuroides or Lolium rigidum. 相似文献
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Flavone eupatorin is one of the constituents of Orthosiphon stamineus, a medicinal herb used in folk medicine in South East Asia for treatment of various disorders. In our study, we investigated the antiproliferative properties of a chloroform extract of the leaves of O. stamineus and of pure eupatorin. The compound was able to reduce the number of viable cancer cells to the same extent as the extract, with IC(50) values in micromolar range. Moreover, both the eupatorin standard and the extract caused cells to arrest in the G2/M phase of the cell cycle. This clearly demonstrates that eupatorin contributes significantly to the overall extract activity. Induction of mitotic catastrophe, accompanied by key molecular events defining apoptosis, is the mechanism of eupatorin-induced cell death. Importantly, eupatorin (at the doses cytotoxic to cancer cells) did not kill normal cells; it only limited migration of HUVEC endothelial cells and their ability to create tubes. The ability of eupatorin to nonspecifically inhibit many protein kinases was proven and is the probable cause of its cellular effects. In summary, eupatorin emerges as a promising agent in anticancer research. 相似文献
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Marie-Liesse Vermeire Lucie Kablan Marc Dorel Bruno Delvaux Jean-Michel Risède Anne Legrève 《European journal of plant pathology / European Foundation for Plant Pathology》2011,131(4):621-630
Silicon (Si) is known to reduce the incidence of pathogens on many plants. Little information is available on the potential
positive effects of Si on the susceptibility of banana (Musa acuminata) to pathogens. Root-rot fungi of the genus Cylindrocladium have been reported, along with endoparasitic nematodes, to be the causal agent of toppling disease and severe yield loss.
The objective of this study was to determine the effects of Si supply on Cylindrocladium spathiphylli infection on banana. Plantlets inoculated by dipping the root system in a conidial suspension of the pathogen were grown
on a desilicated ferralsol and amended, or not, with 2 mM of soluble Si under greenhouse conditions in Guadeloupe. The root
lesion severity was evaluated using the image analysis program WinRHIZO 7, 14 and 21 days after inoculation. A reduction of
about 50% of root necrosis was observed 14 days after inoculation for the Si-supplied plants compared with those not supplied
with Si. The Si amendment also alleviated growth reduction caused by the pathogen. These results suggest that Si could have
a positive effect on banana resistance to C. spathiphylli and provide an environmentally friendly alternative to pesticides for the integrated control of an important crop disease. 相似文献
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High-throughput sequencing has opened up possibilities of detecting new plant pathogens, especially viruses, with relative ease. However, information about biological characteristics and relevance to plant production is usually lacking. Recently, a new strawberry cytorhabdovirus named strawberry virus 1 (StrV-1) was described and characterized at a molecular level. The virus can be transmitted by aphids and is commonly found in commercial plantations. Here, we studied the impact of a sole StrV-1 infection on production in two strawberry cultivars—Darselect and Karmen. All plants infected with StrV-1 remained symptomless during the experiment. In general, Darselect was more resilient to StrV-1 infection, and the average yield per plant was nonsignificantly lowered by 11.7% over the 2-year experiment. In contrast, StrV-1 infection in cultivar Karmen led to a significant yield loss of 31.8%, indicating that the genetic background plays a role. While the average fruit weight and diameter were relatively unaffected, lower yields in infected plants stemmed from a significantly reduced number of inflorescences, by 23.6% and 29.6% in Darselect and Karmen, respectively, which resulted in a reduction in the average number of flowers per plant (decreased by 16.5% and 27.3%, respectively), and hence the number of fruits per plant (by 14.5% and 27.6%, respectively). The StrV-1 load was higher in spring than in autumn, and generally higher in the second year after infection, which corresponded to higher losses in the second harvest, especially in cultivar Karmen. 相似文献
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Petrásek J Mravec J Bouchard R Blakeslee JJ Abas M Seifertová D Wisniewska J Tadele Z Kubes M Covanová M Dhonukshe P Skupa P Benková E Perry L Krecek P Lee OR Fink GR Geisler M Murphy AS Luschnig C Zazímalová E Friml J 《Science (New York, N.Y.)》2006,312(5775):914-918
Intercellular flow of the phytohormone auxin underpins multiple developmental processes in plants. Plant-specific pin-formed (PIN) proteins and several phosphoglycoprotein (PGP) transporters are crucial factors in auxin transport-related development, yet the molecular function of PINs remains unknown. Here, we show that PINs mediate auxin efflux from mammalian and yeast cells without needing additional plant-specific factors. Conditional gain-of-function alleles and quantitative measurements of auxin accumulation in Arabidopsis and tobacco cultured cells revealed that the action of PINs in auxin efflux is distinct from PGP, rate-limiting, specific to auxins, and sensitive to auxin transport inhibitors. This suggests a direct involvement of PINs in catalyzing cellular auxin efflux. 相似文献
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Lucie Stoklasová Jiří Váhala Pavla Hejcmanová 《Journal of animal physiology and animal nutrition》2021,105(4):664-667
For many nondomestic species, nutritional requirements and the challenges faced in their current habitats are unknown. This is the case of small semi-captive population of the critically endangered Western Derby eland held in two wildlife reserves (the Bandia and the Fathala) in Senegal. The aim of this study was to determine the mineral profile (Ca, P, Mg, Cu, Fe, Zn, Se, K, S) in blood serum and to identify potential mineral deficiencies. Serum data (11 individuals) were compared to other Tragelaphineae, where it was lower in almost all elements. Considerably low concentrations were recorded for Cu, Fe and Zn. Animals in the Bandia reserve had higher serum levels of Fe and K compared to the Fathala reserve and a higher serum level of S in the Fathala reserve compared to the Bandia reserve. Recorded mineral levels may reflect most likely the limited mineral background in the local environment. The knowledge of adequate nutritional requirements and health status of these animals is relevant for the conservation breeding programme. No other serum mineral reference values exist for Western Derby eland, neither for free-ranging nor captive animals. Therefore, the knowledge of reference intervals for minerals in serum may serve for monitoring of the population's health. 相似文献
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Desmarchelier A Mujahid C Racault L Perring L Lancova K 《Journal of agricultural and food chemistry》2011,59(14):7659-7665
A liquid chromatography electrospray ionization tandem mass spectrometry method for the determination of patulin in apple- and pear-based foodstuffs was developed. The sample preparation is based on the QuEChERS procedure involving an initial extraction step with water and acetonitrile, followed by a partitioning step after the addition of magnesium sulfate and sodium chloride. The cleanup was performed by using dispersive solid-phase extraction with a mixture of magnesium sulfate, primary secondary amine sorbent, and n-octadecylsiloxane sorbent added together to the extract. The cleaned extract was finally evaporated and reconstituted in water prior to injection. Quantitation was performed by isotope dilution using ((13)C(7))-patulin as internal standard. The method was first fully validated in three different baby food products including apple-pear juice, apple-pear puree, and infant cereals. Then the scope of application of the method was extended to pear concentrate, raw apples, apple flakes (naturally contaminated), dried apples, and yogurt. The sensitivity achieved by the method in all matrices gave limits of detection (LOD) and quantitation (LOQ) of ≤0.5 and ≤10 μg/kg, respectively, which was compliant with maximum levels settled in Commission Regulation (EC) No. 1881/2006. Method performances for all matrices also fulfilled the criteria established in the CEN/TR 16059:2010 document. Indeed, recoveries were within the 94-104% range; relative standard deviations of repeatability (RSD(r)) and intermediate reproducibility (RSD(IR)) were ≤7.5 and ≤13.0%, respectively, and trueness in an infant apple drink (FAPAS 1642) was measured at 99%. 相似文献