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111.
The aim of this investigation was to find a proper harvesting period and establishing fern number, which effects the spear yield, bioactive compounds and antioxidant activities of Asparagus officinalis L. Spears were harvested at 2, 4, and 6 weeks after sprouting. Control for comparison was used without harvest. Spears and total yield increased with prolonged spear harvest period. In harvest of 6 weeks long optimum spear yield was the highest and fern numbers were 5?~?8. Bioactive compounds (polyphenols, flavonoids, flavanols, tannins and ascorbic acid) and the levels of antioxidant activities by ferric-reducing/antioxidant power (FRAP) and cupric reducing antioxidant capacity (CUPRAC) assays in asparagus ethanol extracts significantly differed in the investigated samples and were the highest at 6 weeks harvest period (P?<?0.05). The first and the second segments from the tip significantly increased with the increase of catalase (CAT). It was interesting to investigate in vitro how human serum albumin (HSA) interacts with polyphenols extracted from investigated vegetables. Therefore the functional properties of asparagus were studied by the interaction of polyphenol ethanol extracts with HSA, using 3D- FL. In conclusion, antioxidant status (bioactive compounds, binding and antioxidant activities) improved with the harvesting period and the first segment from spear tip. Appropriate harvesting is effective for higher asparagus yield and its bioactivity.  相似文献   
112.
Summary Resistance of the GaterslebenAegilops collection was studied in relation to the following wheat diseases: stem rust(Puccinia graminis), leaf rust(Puccinia recondita), stripe rust(Puccinia striiformis) and powdery mildew(Erysiphe graminis). Numerous sources of complete, combined or single resistance have been detected in 487 accessions of 21Aegilops species. Potential donors of the complete resistance have been found in diploidAe. speltoides, Ae. longissima ssp.sharonensis, Ae. mark-grafii and tetraploidAe. geniculata. Methods of a transfer of resistance genes from particularAegilops species to the common wheat,Triticum aestivum, are discussed.
Krankheitsresistenz in der GattungAegilops L. — Schwarzrost, Braunrost, Gelbrost und Mehltau
Zusammenfassung Die GaterslebenerAegilops-Kollektion wurde auf Resistenz gegen folgende Weizen-Krankheiten untersucht: Schwarzrost(Puccinia graminis), Braunrost(Puccinia recondita), Gelbrost(Puccinia striiformis) und Mehltau(Erysiphe graminis). Zahlreiche Quellen für Resistenz gegenüber einzelnen Krankheiten, kombinierte Resistenz und auch vollständige Resistenz gegenüber allen Erregern konnten unter den 487 Sortimentsnummern aus 21Aegilops-Arten gefunden werden. Potentielle Donoren mit vollständiger Resistenz wurden bei den diploiden SippenAe. speltoides, Ae. longissima ssp.sharonensis undAe. markgrafii sowie bei der tetraploidenAe. geniculata nachgewiesen. Methoden zur Übertragung der Resistenzgene von den einzelnenAegilops-Arten auf den Weizen,Triticum aestivum, werden diskutiert.

Aegilops L. —
Aegilops :Puccinia graminis, P. recondita, P. striiformis, Erysiphe graminis. , , 487 21 Aegilops. , Ae. speltoides, Ae. longissima ssp.sharonensis, Ae. markgrafii Ae. geniculata. Aegilops Triticum aestivum.
  相似文献   
113.
The Adsorption of Fluoride Ion from Aqueous Solution by Activated Alumina   总被引:1,自引:0,他引:1  
The adsorption of fluoride ion in aqueous solution by using alumina was studied in this research. The experimental resultsindicated that the removal efficiency was influenced significantly by solution pH and the optimum operating pH wasfound to be in the range of 5 to 7. For neutral and acidic solutions, the adsorption capacities of fluoride by alumina wasinterfered by the presence of sulfate. The Langmuir and Freundlich isotherms can well describe the equilibrium behaviorsof the adsorption processes. The experimentally determined lowvalues of activation energy indicate nonspecific adsorption isthe predominant mechanism. The surface reaction-limiting batchkinetic model can adequately describe the removal behaviors offluoride ion by alumina adsorption in the batch system.  相似文献   
114.
Zusammenfassung Mittels der Dünnschichtchromatographie wurde festgestellt, daß das Anthron selektiv mit Ketosen reagieren kann. Für die kolorimetrische Bestimmung der Laktulose wurde Anthron im Medium von Phosphor- und Essigsäure angewandt. Man stellte fest, daß die farbigen Verbindungen des Anthrons mit Laktulose dasBeer'sche Gesetz im Bereich der Laktulosekonzentrationen 0,5 mg/ml bis 1,5 mg/ml erfüllen. Diese Verbindungen entstehen durch Erwärmen der Reagentien bei 100°C während 30 Min. Das Absorptionsmaximum der farbigen Verbindungen der Laktulose mit dem Anthron befindet sich bei der Wellenlänge 427,4 nm. In 92%-iger Äthylalkohollösung kann die Laktulose mit Hilfe der Anthronmethode in Gegenwart verschiedener Laktosemengen bestimmt werden. Diese Laktose kann ein Bestandteil des Gemisches aus Zuckern sein oder sie kann auch in Milchprodukten auftreten. Die im Verhältnis zur Laktulose gleichgroßen Galaktose- und Glukosemengen hindern nicht bei der Bestimmung der Laktulose im Gemisch dieser Zucker.
Summary We have established, with the help of TLC, that anthrone can react selectively with the ketoses. For the colorimetric analysis of lactulose anthrone has been utilised in a medium of phosphoric acid and acetic acid. It has been ascertained that the coloured compounds anthrone with lactulose are following deBeer's law in the range of concentrations going from 0.5 mg/ml to 1.5 mg/ml of lactulose. These compounds are formed by heating the reagents at 100°C during 30 minutes. Maximum absorption of the coloured compounds of lactulose and anthrone is located at 427.4 nm wave length. Lactulose can be determined in 92% ethanol solutions by the anthrone method in the presence of various quantities of lactose. This lactose can be a constituent of a mixture of sugars or be formed in dairy products. The determination of lactulose in the presence of galactose and glucose, mixed in equal quantities, is not impeded.

Résumé Nous avons constaté au moyen de la C.C.M., que l'anthrone peut réagir d'une manière sélective avec les cétoses. Pour l'analyse colorimétrique de lactulose l'anthrone a été utilisée dans un milieu d'acide phosphorique et acide acétique. On a constaté que les composés colorés de l'anthrone avec le lactulose suivent la loi deBeer dans le domaine des concentrations 0,5 mg/ml à 1,5 mg/ml de lactulose. Ces composés se forment par chauffage des réactifs à 100°C pendant 30 minutes. Le maximum d'absorption des composés colorés du lactulose avec l'anthrone se situe à la longueur d'onde de 427,4 nm. Le lactulose peut être déterminé dans une solution d'éthanol à 92% au moyen de la méthode à l'anthrone en présence de différentes quantités de lactose. Ce lactose peut être constituant d'un mélange de sucre ou bien être formée dans les produits laitiers. La détermination du lactulose en présence de galactose et glucose, mélangés en quantité égale, n'est pas génée.
  相似文献   
115.
Treatment combinations of four poinsettia (Euphorbia pulcherrima) cultivars, 20 substrates, and three fertigation treatments were evaluated in a completely randomized block design. Poinsettia cultivars included ‘V-14 Glory’, ‘Red Sails’, ‘Lilo Pink’, and ‘Annette Hegg Top White’. The compost substrates were compost:peat:perlite blended (by vol.) at 2:3:3, 1:1:1, and 2:1:1 ratios. Sunshine Mix 1 and Pro Gro 300S were used as controls. Composts tested were those prepared from crab offal, lime and polymer-dewatered biosolids, municipal solid waste (MSW), yard waste, and poultry litter. Fertigation treatments were initiated on the week of potting, delayed one or two week after potting and applied once per week. Controls produced premium quality plants. Composts prepared from poultry litter, yard waste, polymer-dewatered biosolids, crab offal, and MSW produced good quality plants. Plant width in 25 percent compost treatments were greater than those in 50 percent compost treatments. Total number of branches, plant height, canopy diameter, and plant grade on plants treated with fertilizer on the first week were only three percent greater than in treatments where fertilizer application was delayed one or two weeks.  相似文献   
116.
A fast normalized cross correlation (FNCC) based machine vision algorithm was proposed in this study to develop a method for detecting and counting immature green citrus fruit using outdoor colour images toward the development of an early yield mapping system. As a template matching method, FNCC was used to detect potential fruit areas in the image, which was the very basis for subsequent false positive removal. Multiple features, including colour, shape and texture features, were combined in this algorithm to remove false positives. Circular Hough transform (CHT) was used to detect circles from images after background removal based on colour components. After building disks centred in centroids resulted from both FNCC and CHT, the detection results were merged based on the size and Euclidian distance of the intersection areas of the disks from these two methods. Finally, the number of fruit was determined after false positive removal using texture features. For a validation dataset of 59 images, 84.4 % of the fruits were successfully detected, which indicated the potential of the proposed method toward the development of an early yield mapping system.  相似文献   
117.
“互联网+”时代高校传统教育与管理面临着前所未有的新形势和新挑战,在“互联网+”和高校信息化建设的时代背景下,高校必须要把握变革机遇、重塑管理理念观念、树立互联网思维,准确理解“互联网+”校园的理念和内涵,将新一代信息技术充分应用并深度融入高校教育教学、管理服务中,以构建智能化、智慧型校园为切入点,推进高校信息化校园建设,促进我国高等教育转型升级和一流大学、一流学科建设。  相似文献   
118.
The effect of two bounding walls on the rotational motion of a freely suspended non-Brownian fiber in the simple shear flow at low Reynolds number was investigated numerically using the lattice-Boltzmann method. Data were reported for the fibers with aspect ratios of 8, 10, and 15 under various ratios of wall gap (2h) to fiber length (L). For 2h/L≥3.0, the time-dependent orientation of the fiber is shown to be in quantitative agreement with the Jeffery’s theory for ellipsoids suspended in an unbounded linear shear flow, and the effect of the walls on the rotational period of the fiber is insignificant for all fibers with different aspect ratios. For 1.8≤2h/L<3.0, the results reveal that the walls have different effects on the rotation of fiber. For 2h/L<1.8, the complete periodical motion of the fiber is suppressed. The fiber rotates to nearly aligning with the flow direction, and then ceases to rotate. In this orientation, the walls have a stabilizing effect on the fiber and this effect is more pronounced for the fibers with large aspect ratio. The fiber finally does not orient with the flow direction, but with a small angle with the flow direction, and the angle is an increasing function of the fiber aspect ratio and dependent on the wall gap.  相似文献   
119.
Seed vigour plays an important role in agricultural production, and seeds with high sowing quality are necessary for improving agriculture production. In our study, two connected maize recombinant inbred line (RIL) populations derived from Yu82 × Shen137 and Yu537A × Shen137 crosses were evaluated for the mean germination time (MGT) and other related traits under three artificial ageing treatments. We used meta‐analysis to integrate genetic maps and identify quantitative trait loci (QTLs) across the two populations. In total, 74 QTLs and 20 meta‐QTLs (mQTLs) were identified. Four key mQTLs, mQTL2‐2, mQTL5‐4, mQTL6 and mQTL8, which contained initial QTLs with R2 values >10% and included 5–9 initial QTLs, may be hot spots of important QTLs for the associated traits. Twenty‐two key candidate genes associated with four seed vigour‐related traits mapped to 14 mQTLs. In particular, the GRMZM2G163749, GRMZM2G122172/GRMZM2G554885/GRMZM2G122871 and GRMZM2G150367 genes mapped within the important mQTL5–4, mQTL6 and mQTL8 regions, respectively. Fine mapping for the genetic regions of these three mQTLs merits further study and could be utilized for marker‐assisted breeding.  相似文献   
120.
Non‐pungent bell pepper (Capsicum annuum L.) lacks the cytoplasmic male sterility (CMS) nuclear restorer allele, Rf, and CMS cannot be employed in its F1 hybrid seed production. To demonstrate that the genic male sterility (GMS) system in non‐pungent bell pepper can be converted to the CMS male sterility system, the conversion of GMS to CMS for non‐pungent bell pepper line GC3 was conducted by introgression of S‐type cytoplasm and the Rf allele from tropical pungent donors. After morphological traits were evaluated, two lines from BC1F1 containing S‐type cytoplasm and four lines from BC2F2 containing Rf allele, phenotypically similar to GC3, were obtained and could be employed as CMS male sterile lines and restorer lines for non‐pungent bell pepper. Four molecular markers potentially linked to traits of interest were also evaluated in BC1F1 and BC1F2 populations. This is the first time that GMS has been successfully converted to CMS in bell pepper, a significant contribution for bell pepper hybrid seed production.  相似文献   
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