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1.
Kazimierz Tarasiuk 《今日养猪业》2006,(1):27-28
蓝耳病(PRRS)是目前对猪场经济影响最大的疾病,1989年分离到PRRS病毒后,越来越多地在世界更多的国家和猪场存在,且病毒扩展的速度也非常快.20世纪90年代初,业内认为蓝耳病阳性的猪场应该引进蓝耳病阳性的猪,但这只是20世纪90年代初期的看法.随着时间的推移和蓝耳病的研究进展,这一观点已发生了改变. 相似文献
2.
Dilson A. Bisognin David S. Douches Kazimierz Jastrzebski William W. Kirk 《Euphytica》2002,125(1):129-138
The objectives of this study were to evaluate the use of potato (Solanum tuberosum L.) late blight (Phytophthora infestans (Mont.) de Bary) resistant parents in cultivar development and identify superior clones possessing moderate to high late
blight resistance combined with acceptable maturity and tuber quality. Ninety-five crosses were made between eight unadapted
parents with reported late blight resistance (B0718-3, Bertita, Bzura, Greta, Libertas, Stobrawa, Tollocan and Zarevo) and
susceptible parents (cultivars or advanced breeding clones) adapted to North American growing conditions. A total of 408 field
selected clones were assessed for late blight resistance in the greenhouse and in the field using a mixture of US8 P. infestans isolates (A2 mating type, metalaxyl resistant) that overcame all known R-genes except R8 and R9. Clones with ≤ 10% infected
foliar area in the greenhouse test or ≤ 0.30 RAUDPC (relative area under the disease progress curve) value in the field in
1998 were re-tested in 1999. A total of 118 (29% of 408) putative late blight resistant clones were selected. The eight late
blight resistant parents differed in both the ability to transmit late blight resistance and in the level of resistance transmitted
to the progeny. The Tollocan and B0718-3 families (half-sib progeny) had the greatest degree of resistance and frequency of
resistant clones. Scott-Knott cluster analysis ranked 79 clones (67% of 118) in the high and moderate late blight resistant
groups. Among these 79 clones, 19 clones had vine maturity equal to or earlier than mid-season combined with acceptable tuber
quality. Further selection in 2000 resulted in eight advanced selected clones (six from Tollocan and two from B0718-3 families)
with the same level of resistance as the parent combined with vine maturity and tuber quality equivalent to Atlantic, a standard
cultivar for chip processing in North America. The results indicate that this breeding approach can be used to select parents
for late blight resistance breeding and to identify superior clones with high levels of late blight resistance and marketable
vine maturity and tuber quality.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
3.
On the basis of the fresh weight of apple fruit and its peel and the concentration of bioactive compounds, the total quantity of L-cysteine, glutathione, ascorbate, flavonols, and anthocyanins as well as phenolics was evaluated in a wide range of cultivars and two growing seasons. Apple peel as a contributor to the entire apple quantity of the examined components considerably differed in relation to the investigated compounds and was also highly cultivar dependent. A great amount of flavonols was found in apple peel (approximately 40%), followed by ascorbate (approximately 30%) and total phenolics (approximately 20%), while the lowest contribution was assessed for thiols (approximately 11% and 14% for L-cysteine and total quantity of glutathione, respectively), based on average values for both years. Seasonal variations in the quantity of antioxidants was more pronounced in apple peel, whereas the contribution of apple peel to the whole fruit was predominantly affected by the genotype. A very high positive correlation existed between apple peel and the whole fruit quantity of antioxidants. 相似文献
4.
Vonderheide AP Wrobel K Kannamkumarath SS B'Hymer C Montes-Bayón M Ponce De León C Caruso JA 《Journal of agricultural and food chemistry》2002,50(20):5722-5728
Brazil nuts have been classified as the foodstuffs that contain the highest level of unadulterated selenium, an essential trace element that appears to prevent cancer. To date, characterization of the selenium species in brazil nuts has not yet been investigated. In this work, various sample preparation approaches, including microwave extractions and enzymatic treatments, are examined with the goal of species preservation and subsequent selenium speciation; of these approaches, an enzymatic treatment with Proteinase K proved most effective. High-performance liquid chromatography (HPLC) separation strategies and inductively coupled plasma mass spectrometry (ICP-MS) detection schemes will also be presented. Extracts are evaluated against available standards for the commercially obtainable seleno-amino acids, selenomethionine (SeMet), selenoethionine (SeEt), and selenocystine (SeCys); selenomethionine was demonstrated to be the most abundant of these seleno-amino acids. Further characterization of unidentified selenium-containing peaks is attempted by the employment of several procedures, including electrospray-mass spectrometry (ES-MS). A peptide structure was identified; however, this was considered a tentative proposal due to the large background produced by the extremely complicated brazil nut matrix. 相似文献
5.
Kannamkumarath SS Wróbel K Wróbel K Caruso JA 《Journal of agricultural and food chemistry》2004,52(6):1458-1463
In this work the quantitative determination and analytical speciation of arsenic were undertaken in different types of nuts, randomly purchased from local markets. The hardness of the whole nuts and high lipid content made the preparation of this material difficult for analysis. The lack of sample homogeneity caused irreproducible results. To improve the precision of analysis, arsenic was determined separately in nut oil and in the defatted sample. The lipids were extracted from the ground sample with the two portions of a mixture of chloroform and methanol (2:1). The defatted material was dried and ground again, yielding a fine powder. The nut oil was obtained by combining the two organic extracts and by evaporating the solvents. The two nut fractions were microwave digested, and total arsenic was determined by inductively coupled plasma mass spectrometry (ICP-MS). The results obtained for oils from different types of nuts showed element concentration in the range 2.9-16.9 ng g(-)(1). Lower levels of arsenic were found in defatted material (<0.1 ng g(-)(1) with the exception of Brazil nuts purchased with and without shells, 3.0 and 2.8 ng g(-)(1) respectively). For speciation analysis of arsenic in nut oils, elemental species were extracted from 2 g of oil with 12 mL of chloroform/methanol (2:1) and 8 mL of deionized water. The aqueous layer, containing polar arsenic species, was evaporated and the residue dissolved and analyzed by ion chromatography-ICP-MS. The anion exchange chromatography enabled separation of As(III), dimethylarsinic acid (DMAs(V)), monomethylarsonic acid (MMAs(V)), and As(V) within 8 min. Several types of nuts were analyzed, including walnuts, Brazil nuts, almonds, cashews, pine nuts, peanuts, pistachio nuts, and sunflower seeds. The recovery for the speciation procedure was in the range 72.7-90.6%. The primary species found in the oil extracts were As(III) and As(V). The arsenic concentration levels in these two species were 0.7-12.7 and 0.5-4.3 ng g(-)(1), respectively. The contribution of As in DMAs(V) ranged from 0.1 +/- 0.1 ng g(-)(1) in walnuts to 1.3 +/- 0.3 ng g(-)(1) in pine nuts. MMAs(V) was not detected in almonds, peanuts, pine nuts, sunflower seeds, or walnuts, and the highest concentration was found in pistachio nuts (0.5 +/- 0.2 ng g(-)(1)). 相似文献
6.
Ewa Błońska Marek Pająk Stanisław Małek Kazimierz Januszek 《Communications in Soil Science and Plant Analysis》2017,48(6):692-704
The aim of the present research was to study the long-term effect of serpentinite fertilization with additional nitrogen, phosphorous, and potassium fertilizers on some physicochemical properties and the enzyme activity of acidic soils and needle chemistry in stands of Norway spruce (Picea abies (L.) Karst.). Experimental plots were located in spruce stands in the middle forest zone (900–950 m) on two nappes of the Carpathian flysch: Magura and Silesian. Serpentinite was introduced in autumn 2008 on all plots while the other fertilizers in spring 2009. The effect of fertilization was visible mainly in the humus horizon. No significant changes were found in the deeper mineral soil. The acidity and Al toxicity in the surface horizon were ameliorated through serpentinite fertilization. Five years after fertilization, no significant difference in the fertilization treatments was noted in the chemistry of the spruce needles. 相似文献
7.
8.
Ten coumarins were isolated from Peucedanum luxurians. The rare coumarins stenocarpin, stenocarpin isobutyrate, officinalin, officinalin isobutyrate, 8-methoxypeucedanin and the known xanthotoxin, isoimperatorin, bergaptene, peucedanin and cnidilin were isolated. All isolated compound were identified by means of spectral data. 相似文献
9.
Muñoz AH Kubachka K Wrobel K Corona FG Yathavakilla SK Caruso JA Wrobel K 《Journal of agricultural and food chemistry》2005,53(13):5138-5143
Huitlacoche is the ethnic name of the young fruiting bodies of Ustilago maydis, a common parasite of maize. In Mexico and other Latin American countries, this fungus has been traditionally appreciated as a local delicacy. In this work a metallomics approach was used with the determination of eight elements in huitlacoche by electrothermal atomic absorption spectrometry as one facet of this approach. The results obtained indicated relatively lower concentrations of commonly analyzed metals, as referred to the data reported for other mushroom types. This effect was ascribed to different accessibilities of elements, depending on fungus substrate (lower from plant than from soil). Subcellular fractionation was accomplished by centrifugation of cell homogenates suspended in Tris-HCl buffer. Recoveries of the fractionation procedure were in the range of 71-103%. For six elements (Cr, Cu, Fe, Mn, Ni, and Pb), the mean relative contributions in cytosol, cell walls, and mixed membrane fraction were 50.7, 48.2, and 1.1% respectively. To attain the molecular weight distribution of compounds containing target elements as an additional aspect of the metallomics approach, the fungus extract (1% sodium dodecyl sulfate in Tris-HCl, 30 mmol L(-)(1), pH 7.0) was analyzed by size exclusion chromatography with UV and ICP-MS detection. With spectrophotometric detection (280 nm), the elution of high molecular weight compounds was observed in the form of one peak (MW > 10 kDa), and several lower peaks appeared at higher retention times (MW < 10 kDa). On ICP-MS chromatograms, a coelution of (59)Co, (63)Cu, (57)Fe, (202)Hg, (60)Ni, and (80)Se with the first peak on the UV chromatogram was clearly observed, indicating that a fraction of each element incorporated with high molecular weight compounds (12.7, 19.8, 33.7, 100, 19.4, and 45.8%, respectively, based on the peak area measurements). From a comparison of (80)Se and (33)S chromatograms (for sulfur analysis, the extract was obtained in the absence of SDS), both elements coeluted with the first UV peak, but their lower molecular weight compounds were apparently different. These findings may contribute to a better understanding of the accumulation of elements in mushrooms. 相似文献
10.
Studies on Effective Methods to Control Cockroaches Abroad Ships
Organization and common methods of the control or arthopods and rodents abroad ships of the Polish navy and merchant marine are discussed. It is outlined that disinsecting is mainly based upon the application of hydrogen cyanide (Zyklon B) and to a minor extend upon the application of chemicals acting as contract poisons. However, the methods mentioned which have been applied so far occasionally and on a private basis, are generally little effective.More effective methods of cockroach control in this environment were tried by using chemical preparations (insect-killing lacquer made by Azot, the Gertoks preparation made by Fregata and the dust, Blattosep, by Azot) as well as biological preparations ofBac. thuringiensis (Biotrol 25 W, Biotrol 5 D, E-58 made by Buean Park and Institut Pasteur). By these methods, a favourable disinsecting effect was achieved, so that an application of these preparations instead of the little effective, expensive, and costly gassing with hydrogen cyanide (Zyklon B) is recommended.
81-304 Gdynia (Polen), Slaska 72 m 40 相似文献
81-304 Gdynia (Polen), Slaska 72 m 40 相似文献