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排序方式: 共有90条查询结果,搜索用时 15 毫秒
1.
Katarzyna Sosnowska Teresa Cegielska-Taras Alina Liersch Wojciech M. Karłowski Jan Bocianowski Laurencja Szała Katarzyna Mikołajczyk Wiesława Popławska 《Euphytica》2017,213(9):212
The allopolyploidization event that created cultivated oilseed rape Brassica napus L, followed by intense breeding, reduced its genetic diversity. Resynthesized (RS) B. napus L. obtained by interspecific hybridization between genotypes of B. rapa L. and B. oleracea L. can be a valuable source for broadening genetic diversity in cultivated oilseed rape. In this study, we determined the extent of DNA polymorphism among natural accessions of oilseed rape, resynthesized B. napus, their parental species and double-low quality semi-RS lines carrying the Rfo gene. Using 10 selected primer combinations, 522 polymorphic AFLP markers were scored in the complete set of 100 Brassica sp. To detect relationships between these genotypes, a cluster analysis was performed using the Jaccard’s distance. Resynthesized allopolyploids clustered directly between their diploid parents. Cultivated accessions of oilseed rape created a compact group away from resynthesized allopolyploids as well as semi-RS lines. The natural oilseed rape group, which consists of 49 cultivars and breeding lines of oilseed rape, is characterized by lower genetic diversity than the group of 33 accessions of resynthesized oilseed rape, and the analysis showed that the double-low quality semi-RS lines represent a specific genetic variation of B. napus. The de novo resynthesized B. napus lines and the semi-RS lines of double-low quality generated from them, provide a significant opportunity for enrichment the gene pool of oilseed rape. 相似文献
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3.
Principal component analysis (PCA) and cluster analysis werecarried out on beach litter found primarily along theBristol Channel, U.K., together with beaches located aroundthe Principality of Wales. Both techniques indicated threebeach survey sites as outliers, with distinctive beachlitter profiles. PCA distinguished between riverine, sewagerelated, fishing and shipping sourced items, but did notproduce a coherent grouping for beach user litter. This wasattributed to a difference in modes of transport. Beachesfrom mid and north Wales, which had small litter amounts,were not differentiated from the central grouping. Thewestern edge of the Channel was more heavily influenced byshipping and fishing inputs than was the eastern portion.Cluster analysis showed a discrete group of beaches locatedmainly on the southern side of the Bristol Channel. 相似文献
4.
Tudor H. Thomas 《Pest management science》1974,5(1):87-100
The use of growth regulators to induce specific modifications in the growth of crops produced for processing is discussed. Increases in yield may be obtained by some treatments but more important effects on uniformity, quality, ease of harvesting and short-term storage may also be achieved. The results of experiments on stem extension of calabrese, chemical stopping and defoliation of Brussels sprouts, root/shoot ratio modification of root crops and short-term storage of green vegetables are presented. It is concluded that although so far, few commercial applications have been discovered, the requirements for growth regulation justify the search for new, more reliable synthetic growth regulators by improving screening tests and more efficient field trials. The use of herbicides on crops grown for processing is also discussed briefly and it is concluded that the prime requirement is for more efficient post-emergence herbicides. 相似文献
5.
Leonardo E. Taccari Alina G. Greslebin María E. Salgado Salomn María L. Vlez 《Forest Pathology》2019,49(2)
Phytophthora austrocedri is a pathogen of Austrocedrus chilensis causing “Mal del Ciprés” (cypress sickness) in Patagonia and killing Juniperus communis in Britain, along with other species in the Cupressaceae. The evident association of the pathogen with members of the Cupressaceae makes it necessary to study the susceptibility of other species related to A. chilensis to prevent the emergence of new diseases. The present study tested the pathogenicity of P. austrocedri to three native and endemic conifers in South America: Fitzroya cupressoides, Pilgerodendron uviferum and Araucaria araucana. The results showed that F. cupressoides and P. uviferum were highly susceptible to P. austrocedri. Since these are endangered tree species, the outcome of this study is crucial for governmental agencies, policymakers and stakeholders. 相似文献
6.
R A Tudor M G Papich W R Redding 《Journal of the American Veterinary Medical Association》1999,215(4):503-506
OBJECTIVE: To evaluate pharmacokinetics of once daily i.v. administration of gentamicin sulfate to adult horses that had abdominal surgery. DESIGN: Prospective study. ANIMALS: 28 adult horses that underwent abdominal surgery for colic. PROCEDURE: 14 horses were treated with each dosage of gentamicin (i.e., 6.6 or 4 mg/kg, i.v., q 24 h) and blood samples were collected for pharmacokinetic analysis. Plasma gentamicin concentrations were measured by use of a fluorescence polarization immunoassay. Pharmacokinetic analysis measured the elimination half-life, volume of distribution, and gentamicin total systemic clearance. Treatment outcome, CBC, and serum creatinine concentrations were recorded. RESULTS: 1 horse in the high-dosage group died. All other horses successfully recovered, and did not develop bacterial infection or have evidence of drug toxicosis resulting in renal injury. Mean pharmacokinetic variables for gentamicin administration at a high or low dosage (i.e., 6.6 or 4 mg/kg, i.v., q 24 h) were half-life of 1.47 and 1.61 hours, volume of distribution of 0.17 and 0.17 L/kg, and systemic clearance of 1.27 and 1.2 ml/kg/min, respectively. Mean serum creatinine concentration was 1.74 and 1.71 for the high and low dosages, respectively, and serum creatinine concentration was not correlated with gentamicin clearance. CONCLUSIONS AND CLINICAL RELEVANCE: Gentamicin administration at a dosage of 4 mg/kg, i.v., every 24 hours, will result in plasma concentrations that are adequate against susceptible bacteria with a minimum inhibitory concentration (MIC) of < or = 2.0 micrograms/ml. Gentamicin administration at a calculated dosage of 6.8 mg/kg, i.v., every 24 hours will result in optimum plasma concentrations against susceptible bacteria with a MIC of < or = 4.0 micrograms/ml. 相似文献
7.
Janusz Popawski Boena ozowicka Alina T Dubis Barbara Lachowska Zbigiew Winiecki Jan Nawrot 《Pest management science》2000,56(6):560-564
All isomers of α‐asarone [(E)‐4‐prop‐1‐enyl‐1,2,5‐trimethoxybenzene] were tested for their feeding deterrent activity against adults of Sitophilus granarius and Tribolium confusum and larvae of Trogoderma granarium and Tribolium confusum. (E)‐2‐prop‐1‐enyl‐1,3,5‐trimethoxybenzene exhibited the strongest deterrent activity against all the species tested. The total coefficients of deterrency for this compound were 140.6 and 169.7 for Tribolium confusum adults and larvae, respectively, and 144.9 and 104.6 for larvae of Trogoderma granarium and adults of Sitophilus granarius, respectively. © 2000 Society of Chemical Industry 相似文献
8.
Development of efficient and eco-friendly sorbents used for selective oil removal after oil spill disasters is one of the main topics in environmental science. By using various cellulosic materials coated with graphene flakes, using simple, one-step dip-coating method, it was possible to manufacture environmentally friendly, selective oil sorbents. The cellulosic materials of different yarn size and distribution such as cotton roving, gauze, fabric, and cellulosic wipe and Whatman filter paper were chosen. The scanning electron microscopy showed that simple dip-coating of any cellulosic materials into graphene dispersion creates a uniformly distributed nanomaterial coating. The wetting tests confirmed that the coating endowed cellulosic materials with hydrophobic properties, regardless of their initial yarn distribution and purity. Moreover, the water repellent samples were simultaneously highly sorptive towards oils and organic solvents. Sorption tests performed for a representative group of organic solvents and oils have shown that depending on cellulosic material the oil sorption capacity varied from 4 g/g to 33 g/g for cotton fabric and roving, respectively. Moreover, the absorption selectivity of chloroform versus water exceeded 90 % for each sample and reached over 99 % for the graphene coated cotton roving and gauze. Finally, the recyclability tests have shown that graphene coated materials are less fragile for reuse than naturally hydrophobic sorbents. 相似文献
9.
Different vegetal biomass resources such as Picea abies bark, Castanea sativa chestnuts shell and Asclepias syriaca plant were considered to provide a source of natural bioactive compounds, which can be properly used in several directions such as: plant growth regulators and amendments in bioremediation. Having in mind a complex processing biomass technology, these raw materials are used in a first step to separate bioactive compounds by an aqueous extraction. The obtained extracts containing polyphenols were tested in germination tests to evaluate their influence on cadmium bioaccumulation in oat plant (Avena sativa). It was observed that the mentioned extracts modulated cadmium bioaccumulation, photosynthesizing pigments biosynthesis, plant growth and its development depending on metal ion concentration (5, 12.5, 25 mg/L), and extracts composition determined by vegetal raw material and their total polyphenols content (130, 122, 114 mg/L related to gallic acid). FTIR spectra and histo-anatomical cross section of the roots certify that P. abies bark and A. syriaca plant extracts amendments stimulated cadmium bioaccumulation, promoting the translocation of heavy metals to the aerial part of the plant, meanwhile chestnuts shell extract reduced the mobility of cadmium determining in situ inactivation of heavy metal ions. 相似文献
10.
Tatiana A. Sorkina Alexander Yu. Polyakov Natalia A. Kulikova Anastasia E. Goldt Olga I. Philippova Alina A. Aseeva Alexey A. Veligzhanin Yan V. Zubavichus Denis A. Pankratov Eugene A. Goodilin Irina V. Perminova 《Journal of Soils and Sediments》2014,14(2):261-268