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51.
Marine bio-sourced chitosan nanoparticles (CSNP) are antimicrobial and immunomodulatory agents beneficial for fish medicine. Herein, dietary CSNP was investigated for the amelioration of the systemic inflammatory responses of an induced fish model. One hundred and forty-four rainbow trout were assigned to one pathogen-free and non-supplemented group (negative control), and three challenged groups: non-supplemented (positive control), CSNP-preventive, and CSNP-therapeutic. After a feeding experiment extended for 21 days, the organosomatic indices (OSI) and molecular aspects were assessed. After a challenge experiment extended for further 28 days, CSNP-therapeutic intervention was assessed on fish survival and systemic inflammatory responses on pathology, histo-morphology, and molecular aspects. With CSNP administration, OSI nonsignificantly decreased and the relative expression of targeted inflammatory-mediator genes was significantly increased. The CSNP-therapeutic fish showed an RPS of 80% as compared to the positive control group, and CSNP-therapeutic administration retained the highest gene expression augmentation up to 28 days after the challenge. Notably, the splenic reticulin fibers framework of the CSNP-therapeutic group retained the highest integrity among the groups during the infection. After recovery, reticulin fibers density in the CSNP-therapeutic samples was significantly higher than in the negative control group, which indicates high innate immunity. Thus, CSNP showed promising biotherapeutic features enhancing fish resistance against infections.  相似文献   
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53.
To study the effect of soil application of potassium humate (KH) (0, 70 and 140 Kg ha?1) on agronomic, biochemical attributes, and yield and its components on bean (Phaseolus vulgaris L.) cultivars ‘Bronco’ grown under two sites having different level of salinity (EC = 3.00 or 5.00 ± 0.20 dS m?1). Two field trials were conducted at the Agriculture Test Station, Faculty of Agriculture, Fayoum University, in 2014 and 2015. The obtained results indicated that addition of KH increased all of the studied growth parameters, i.e. plant height, number of leaves, leaf area, stem diameter and canopy dry weight. Moreover addition of KH significantly increased membrane permeability measurements. KH significantly increased chemical composition related to salt tolerant either inorganic e.g. N, P, K, and decreased Na and Cl contents of leaves or organic components e.g. chlorophyll a + b, carotenoids, anthocyanin total phenolics, total flavonoids and proline. DPPH radical-scavenging activity and yield and its components were increased. The soil application of KH was found to be highly effective at improving the growth and yield of bean plants by alleviating the inhibitory effects of soil salinity stress.  相似文献   
54.
Im Internationalen organischen Stickstoff‐Dauerdüngungsversuch (IOSDV) hatte die organisch‐mineralische Düngung starken, von der Jahreswitterung modifizierten Einfluß auf die Ertrags‐ und Qualitätsbildung von Winterweizen. Anhand von Blattflächenindex‐Messungen konnten Wachstum und Entwicklung des Winterweizens in Abhängigkeit von den geprüften Faktoren dargestellt werden. Auf den Kornertrag wirkte sich am stärksten die Jahreswitterung aus, gefolgt von der mineralischen N‐Düngung und der organischen Düngung. Dies beruhte auf den Bodenverhältnissen am Versuchsstandort. Trockenperioden während der Blütenbildungsphase, die insbesondere durch Wasserdefizite verursacht wurden, führten vor allem bei der Kornzahl je Ähre und Bestandesdichte zu starken Reduktionen. Im Mittel der Jahre wurde mit 60 kg/ha N‐Düngung das Erfragsoptimum erreicht. Höhere N‐Mengen waren nicht effektiv. Die organische Düngung in Form von “Stallmistdüngung”; und “Stroh‐, Grün‐, Rübenblattdüngung”; führte beim Winterweizen zu signifikanten Mehrerträgen, wobei die größten Unterschiede bei Verzicht auf Mineral‐N‐Düngung auftraten. Die Backqualität der B‐Weizensorte Ares war primär von der mineralischen N‐Düngung abhängig. Die erforderlichen Werte für Weichweizen wurden überwiegend erst mit 110 bzw. 160 kg/ha N Mineral‐N‐Düngung erreicht. Mit organischer Düngung und vor allem durch Rübenblattdüngung wurde die Backqualität des Weizens sowohl in den Varianten ohne Mineral‐N als auch in Kombination mit der mineralischen N‐Düngung verbessert.  相似文献   
55.
The incubation period ofM. incognita acrita eggs took 24–72 hours till the appearance of the second larval stage hatching from eggs in the laboratory at 25±5°C and at 60±5 R. H. The second larval stage, was observed in cotton roots 48 hours after the addition of it to soil beside cotton seedlings. The 3rd and 4th larval stage and adult female were observed in cotton roots 7, 11, and 24 days, respectively, after the addition of second larval stage to soil beside cotton seedlings. The total life cycle ofM. incognita acrita on cotton, (Gossypium barbadense) lasted for 33–38 days, at 25±5°C and at 60±5 R. H.  相似文献   
56.
Effect of some nutritional plant sprays on the population of Tetranychus arabicus (Attiah) (Acarina, Tetranychidae) Studies on the effect of inorganic compounds on the population density ofT. arabicus indicated that all materials gave over 50% reduction after 15 days except chromic chloride and magnesium oxide which gave only 33% each, while potassium iodine built up mites population. As such, these compounds are potentially important mites-control chemicals. Also data showed conclusively that inorganic compounds may be used as well to manipulate host plant resistance, as to correct crop nutritional difficiency. However, the mode of action and the time of application of these compounds under natural field conditions still need further investigations.   相似文献   
57.
Summary Three methods that have been suggested as inexpensive for characterisation of gum arabic were evaluated in characterising and monitoring gum arabic of commerce. The methods were; physico-chemical and carbohydrate analysis (analytical), determination of molecular mass by gel permeation chromatography (gpc) and an Enzyme Linked Immunosorbent Assay (ELISA). The results revealed that gpc provides quick and consistent information on gum arabic of commerce from Acacia senegal. It was able to detect the three chemical species; Arabinogalactan protein complex (AGP), Arabinogalactan (AG) and Glycoprotein (GP) fractions that are typical of A. senegal and could differentiate gum from the two varieties of A. senegal, i.e., var. senegal and var. kerensis on the basis of the enhanced UV peaks in the later. It was able to distinguish gums from different Acacia species as well as suspected contaminants. The analytical method could differentiate between the two varieties of A. senegal on the basis of optical rotation, protein content and viscosity which were noted as basic parameters for comparison. However, where the proposed FAO (1990) specifiction was applied in its present form, it failed to adequately characterise gum from var. kerensis as gum arabic. Secondly, natural product variability i.e., the observed between sample variation made the method to have limited application in adequately characterising gum arabic from even a single source. The method was able to distinguish gums from the other Acacia species purely on the basis of optical rotation though information on nitrogen and sugar composition was also invaluable. Generating data on the composition of sugars requires time that militates against the method as a slow process. Because of the overlap in the analytical parameters for some samples, it could be adequately characterise two of the samples that were presented as suspected contaminants. Nonetheless, by combining information of gpc and analytical data, a better evaluation of the gums was achieved. The method of Elisa has a future scope but will require refining it by utilising monoclonal antibodies to be developed for it to be more specifc in characterising gum arabic from A. senegal. The authors wish to thank Dr. P. A. Williams of the North East Wales Institute, Deeside, Clwyd, UK for the use of the gpc and Elisa facilities. B.N.C. is grateful to the Kenyan and British governments for financial support.  相似文献   
58.
A suppressive effect was obtained by the henna plant (Lawsonia inermis) againstM. incognita development. Henna reduced tomato root gall numbers, number of the egg-laying females and rate of the nematode reproduction, when tomato and henna were grown together. Also, same, reduction in these nematode biological processes was found, when tomato plants were grown in soil containing root exudates of henna, but with less amount. When henna was grown alone, root gall index and the rate of nematode reproduction reduced to 75 and 99%, respectively, compared with those of tomato grown alone.  相似文献   
59.
The effectiveness of intercropping tagetes with tomato in comparison with the natural root exudates of tagetes onMeloidogyne javanica nematode population and galls on tomato cultivated in sandy soil was studied. Both tagetes roots extracts and intercropping tagetes with tomato significantly reducedM. javanica nematode population, egg masses and galls on tomato. Intercropping tagetes with tomato was more effective in reducing root-knot nematode population and galls than treating tomato with natural root extracts of tagetes.Therefore, intercropping resistant plant with susceptible host to nematode is a new and good approach to nematode control.
Zusammenfassung Es wurde die Wirkung des Pflanzens vonTagetes zwischen Tomaten im Vergleich zur Beigabe von Wurzel-Exudaten vonTagetes zu den Tomaten auf den NematodenMeloidogyne javanica in Sandboden untersucht. Beide Verfahren reduzierten signifikant die Zahl der Nematoden, die Eigelege und Gallenbildungen an den Tomaten. Jedoch wirkte die Zwischenpflanzung vonTagetes besser als die Hinzufügung vonTagetes-Wurzelexudaten.Auf Grund der Ergebnisse bietet das Zwischenpflanzen einer resistenten Pflanzenart zu einer nematoden-empfindlichen Pflanzenart einen neuen Weg der Nematodenbekämpfung.


With one table  相似文献   
60.
Field experiment was conducted at a site naturally infested withTylenchulus semipenetrans to explore the effect of sincocin AGTM as a biocidal agent at 2000 ppm in controlling citrus nematodes. Sincocin AGTM significantly reduced citrus nematode population in both soil and roots ofCitrus sinesis, and enhanced both growth of orange trees and soil mites especially the mesostigmatide mites. In treated soil, the nature nematode feeders, mesostigmatide mites were increased by 140% and 243%, one month and two months, respectively, post application.  相似文献   
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