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1.
Provision of feed supplies for the rapidly growing livestock population is essential in West Asia. Shortages can be alleviated by growing forage crops in the existing fallow lands.
Narbon vetch (Vicia narbonensis L.) is a leguminous species with high yield potential, drought tolerance and cold resistance. It could be used for grain and straw production as source for animal feed in dry areas. It is good source of protein with seeds contain 28 % protein yielding 364 kg per hectare protein, whilst straw contains 9 % protein and yields a similar amounts of digestible protein per hectare.
Nine promising lines of Narbon vetch developed at ICARDA were tested at two sites over four years under rainfed conditions. Since climatic conditions were considered to be of considerable importance, each site in each year was treated as a separate environment to give eight environments with annual rainfall varied from 195 to 504 mm.
Narbon vetch possessed high seedling vigour with rapid winter growth and negligible cold damage. Grain yield varied form 0.47 to 1.90 t/ha, with a harvest index varying from 30 to 40 %. The data indicated that below 300 mm rainfall the grain yield varied from 0.47 t/ha when rain fall was 195 mm to 1.4 t/ha when rainfall was 245 mm. Most of the lines had wide adaptation to dry areas in terms of both grain yield and stability. Climate, except early spring rains had little effect on biological and grain yields. 相似文献
Narbon vetch (Vicia narbonensis L.) is a leguminous species with high yield potential, drought tolerance and cold resistance. It could be used for grain and straw production as source for animal feed in dry areas. It is good source of protein with seeds contain 28 % protein yielding 364 kg per hectare protein, whilst straw contains 9 % protein and yields a similar amounts of digestible protein per hectare.
Nine promising lines of Narbon vetch developed at ICARDA were tested at two sites over four years under rainfed conditions. Since climatic conditions were considered to be of considerable importance, each site in each year was treated as a separate environment to give eight environments with annual rainfall varied from 195 to 504 mm.
Narbon vetch possessed high seedling vigour with rapid winter growth and negligible cold damage. Grain yield varied form 0.47 to 1.90 t/ha, with a harvest index varying from 30 to 40 %. The data indicated that below 300 mm rainfall the grain yield varied from 0.47 t/ha when rain fall was 195 mm to 1.4 t/ha when rainfall was 245 mm. Most of the lines had wide adaptation to dry areas in terms of both grain yield and stability. Climate, except early spring rains had little effect on biological and grain yields. 相似文献
2.
1. Under summer conditions in north Iraq, 2 000 chicks were reared for 56 d in two broiler houses. One house was provided with two air‐coolers. The birds were housed at densities of eight to 16 birds/m2.
2. Differences in weight gain between birds in cooled and uncooled houses ranged from 101.5 g at eight birds/m2 to 385 g at 16 birds/m2. Food consumption increased gradually with increasing bird density. Food conversion efficiency, meat yield and carcass conformation were much better in the cooled house than under conventional conditions.
3. The financial return/m2 ranged from 2.30 to 4.51 ID1 in the cooled house, compared with 2.01 to 2.77 ID in the uncooled house at different floor densities. 相似文献
3.
P.A. Benjama M. El Gadda E. El Boustani C. El Modafar X. Nesme J. Cubero 《EPPO Bulletin》2004,34(3):403-406
Le meilleur moyen de contrôle du crown gall ( Agrobacterium tumefaciens ) est la prévention et donc la détection de la bactérie pathogène dans les sols prévus pour les pépinières. Pour cela nous avons essayé une approche moléculaire utilisant la PCR pour caractériser le plasmide pTi par le couple des amorces spécifiques F14/F44 dans les sols de diverses régions marocaines. Cette technique de détection représente un indicateur potentiel d'avertissement sur l'état d'infection des sols et plants par A. tumefaciens qui permet ainsi de déclencher la lutte biologique par le NoGall, produit commercial australien, hébergeant l'antagoniste K1026 . 相似文献
4.
S. T. Elazab D. E. Schrunk R. W. Griffith S. M. Ensley G. Dell'Anna K. Mullin M. G. Elsayed M. S. Amer S. M. El‐Nabtity W. H. Hsu 《Journal of veterinary pharmacology and therapeutics》2018,41(3):374-377
The pharmacokinetics of cefquinome were studied in healthy and Pasteurella multocida‐infected rabbits after a single intramuscular (IM) injection at 2 mg/kg of its sulfate salt. Twelve female New Zealand white rabbits (2.0–2.5 kg) were used; six of them served as controls, and the other six had been infected with P. multocida; the experiments were conducted 1–2 days after nasal inoculation of P. multocida when rabbits showed the signs of respiratory infection. Plasma concentrations of cefquinome were determined using high‐performance liquid chromatography. The values of elimination half‐life, area under the curve, area under the first moment curve, and mean residence time were significantly lower in infected rabbits (0.48 hr, 4.54 hr*μg/ml, 3.63 hr* hr*μg/ml and 0.8 hr, respectively) than healthy rabbits (0.72 hr, 9.11 hr*μg/ml, 9.85 hr* hr*μg/ml and 1.1 hr, respectively), whereas total body clearance was significantly higher in infected than healthy rabbits. Therefore, P. multocida infection caused significant changes in some of the pharmacokinetic parameters of cefquinome in rabbits. These pharmacokinetic changes may affect dose regimen when used in P. multocida‐infected rabbits. 相似文献
5.
Muneera S. M. Al-Saleem Wafaa H. B. Hassan Zeinab I. El Sayed Mahmoud M. Abdel-Aal Wael M. Abdel-Mageed Eman Abdelsalam Sahar Abdelaziz 《Marine drugs》2022,20(5)
Marine sponge-derived endozoic fungi have been gaining increasing importance as promising sources of numerous and unique bioactive compounds. This study investigates the phytochemical profile and biological activities of the ethyl acetate extract of Penicillium chrysogenum derived from Cliona sp. sponge. Thirty-six compounds were tentatively identified from P. chrysogenum ethyl acetate extract along with the kojic acid (KA) isolation. The UPLC-ESI-MS/MS positive ionization mode was used to analyze and identify the extract constituents while 1D and 2D NMR spectroscopy were used for kojic acid (KA) structure confirmation. The antimicrobial, antioxidant, and cytotoxic activities were assessed in vitro. Both the extract and kojic acid showed potent antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa with MIC 250 ± 0.82 µg/mL. Interestingly, the extract showed strong antifungal activity against Candida albicans and Cryptococcus neoformans with MIC 93.75 ± 0.55 and 19.53 ± 0.48 µg/mL, respectively. Furthermore, KA showed the same potency against Fusarium oxysporum and Cryptococcus neoformans with MIC 39.06 ± 0.85 and 39.06 ± 0.98 µg/mL, respectively. Ultimately, KA showed strong antioxidant activity with IC50 33.7 ± 0.8 µg/mL. Moreover, the extract and KA showed strong cytotoxic activity against colon carcinoma (with IC50 22.6 ± 0.8 and 23.4 ± 1.4 µg/mL, respectively) and human larynx carcinoma (with equal IC50 30.8 ± 1.3 and ± 2.1 µg/mL, respectively), respectively. The current study represents the first insights into the phytochemical profile and biological properties of P. chrysoenum ethyl acetate extract, which could be a promising source of valuable secondary metabolites with potent biological potentials. 相似文献
6.
The magnitude of nitrogen fixation in an inorganic fertilized and cereal fed system (fish pond) was measured by an in situ application of the acetylene reduction method. The effects of inorganic fertilization were intensively examined. In comparison with natural lakes, the fish ponds exhibited a relatively low fixation rate. The midday nitrogen fixation rate was usually less than 30 μg at N·m?2·h?1. The total income was equal to 5.7 kg N·ha?1 or 0.575 g N·m?2 for the growing season. Fish-induced bioperturbation and nitrogen fertilization, in the form of inorganic and organic fertilizers and foods, are considered to be the major regulatory factors in nitrogen fixation. 相似文献
7.
Summary Potato blackleg has been known in Roumania for more than 35 years, but has become increasingly serious in recent times. The
disease is mainly restricted to the central and northern regions, which have a rainy climate with moderate temperatures. In
areas where the climate is warm and dry, the disease appears only sporadically, and even then, its development is slow. The
principal means of transmission of the disease from one year to another is by infected tubers, the causal organ does not persist
long in unsterile soil.
Potato blackleg and soft rot in Roumania is produced not only byE. atroseptica, for an important part in the disease complex especially in storage is played by the bacteriaE. carotovora andE. aroideae. E. atroseptica, owing to its special preference for the stems of the plants, is considered as the principal pathogenic agent, while the
other two organisms occur more frequently in the tubers.
It is considered that the divergent characteristics of the organisms justify keeping them as two or even three separate species
and not as variants of a single species.
Paper read to the Pathology Section of the Second Triennial Conference of the European Association for Potato Research, Italy, September 1963. 相似文献
Zusammenfassung In den Jahren 1961 bis 1963 wurden am Biologischen Institut Traian Savulescu in Bukarest, Rum?nien, Untersuchungen durchgeführt über die Verbreitung der Schwarzbeinigkeit bei Kartoffeln im Zusammenhang mit den klimatischen Verh?ltnissen in Rum?nien, mit den Bedingungen, unter welchen die Infektion und die übertragung der Krankheit stattfindet, mit der Etiologie der Krankheit in Rum?nien und mit gewissen charakteristischen Eigenschaften der Krankheitserreger. Kartoffel-Schwarzbeinigkeit ist in Rum?nien schon seit mehr als 35 Jahren bekannt, aber in letzter Zeit hat sie ernstere Formen angenommen. Die Infektion im Feld schwankt von 1–15% und nimmt w?hrend der Lagerung zu. Die Krankheit beschr?nkt sich haupts?chlich auf die zentralen und n?rdlichen Regionen des Landes, wo ein regnerisches Klima mit m?ssigen Temperaturen vorherrscht. Im Süden, wo Frühling und Sommer in der Regel heiss und trocken sind, scheint sie eigentlich nicht vorzukommen, selbst nicht in Feldern, die mit Knollen aus befallenen Gebieten bepflanzt sind. Es ist festgestellt worden, dass die übertragung dieser Krankheit von einem Jahr auf das andere haupts?chlich durch befallene Knollen geschieht. Der Boden bildet nur in dem Mass eine Infektionsquelle, als er nicht verfaulte Reste von kranken Pflanzen enth?lt. Es wurde dargelegt, dass die Bakterien in nicht sterilem Boden ihre überlebensf?higkeit rasch verlieren (Tabelle 1). Was die Etiologie der Schwarzbeinigkeit betrifft, wurde herausgefunden, dass nebenErwinia atroseptica—in Rum?nien bis jetzt als die einzige Ursache dieser Krankheit angenommen — auchE. carotovora undE. aroideae, speziell w?hrend der Lagerung, eine wichtige Rolle im Krankheitskomplex spielen. Unsere Beobachtungen und Untersuchungen haben ergeben, dassE. atroseptica der Hauptkrankheitserreger im Feld ist, der besonders die Stengel bef?llt. Die beiden andern Bakterien kommen ebenfalls vor, doch werden sie gew?hnlich auf den Knollen am Lager gefunden, wo sie — unter günstigen Bedingungen — einen viel h?ufigeren Befall erzeugen k?nnen alsE. atroseptica. Es wurde festgestellt, dass sowohl Eigenschaften, wie der Grad der Pathogenit?t an Stengeln und Knollen, Reaktionen auf Zuckern und besonders das Verhalten auf Maltose und auf durchtr?nktes Korn-Pepton-Glukose-Agar-Medium, das Wachstum bei hohen Temperaturen (Tabelle 2) und serologische Reaktionen (Tabelle 3) wie auch toxische und immunologische Wirkungen auf Tiere bei der Unterscheidung der drei Bakterien von Nutzen sind. Es wird darauf hingewiesen, dass die hier berichteten Ergebnisse die Ansicht jener Forscher best?rken und rechtfertigen, die glauben, dass die drei Bakterien als verschiedene Arten betrachtet werden sollten.
Résumé A l'Institut de Biologie Traian Savulescu à Bucarest. Roumanie, les recherches suivantes ont été effectuées durant la période 1961–1963; l'apparition de la maladie de la jambe noire en relation avec les conditions climatiques en Roumanie, les conditions sous lesquelles ont lieu l'infection et la transmission de la maladie, l'étiologie de la maladie en Roumanie et certains caractères des pathogènes. La jambe noire de la Pomme de terre est connue en Roumanie depuis plus de 35 ans mais est devenue progressivement grave dans les derniers temps. L'infection dans les champs varie de 1 à 15% et augmente pendant la conservation. La maladie est essentiellement limitée aux régions du centre et du nord du pays qui ont un climat pluvieux et des températures modérées. Dans le sud, où le printemps et l'été sont habituellement chauds et secs, la jambe noire semble être réellement absente, même dans les champs plantés avec des tubercules provenant de régions infectées. Il a été établi que la transmission de la maladie d'une année à l'autre a lieu principalement par les tubercules infectés, le sol étant la source d'infection dans la seule mesure où il contient des restes non détruits de plantes malades. Il a été démontré que les bactéries perdent rapidement leur viabilité dans les sols non stériles (Tableau 1). Concernant l'étiologie de la jambe noire, on a trouvé que outreErwinia atroseptica que, jusqu'à présent, on croyait être la seule cause de la maladie en Roumanie,E. carotovora etE. aroideae jouent également un r?le important, spécialement pendant la conservation. Selon nos observations et expériences,E. atroseptica est le principal agent pathogène dans le champ, montrant une préférence marquée pour les tiges, tandis qu'apparaissent aussi les deux autres bactéries qui, toutefois, sont plus communément trouvées sur les tubercules pendant la conservation; à ce moment, sous des conditions favorables, les attaques de ces dernières peuvent être beaucoup plus grandes que celles deE. atroseptica. Les déterminations des comportements suivants se sont révélées pleinement utiles pour différencier les trois bactéries: les degrés d'attaques sur tiges et tubercules, les réactions sur sucres et spécialement leurs réactions sur maltose et sur milieu agar glucose peptone de grains trempés, leur développement à hautes températures (Tpableau 2) et leurs réactions sérologiques (Tpableau 3) aussi bien comme effets toxiques qu'immunologiques sur les animaux. Les résultats rapportés ici prouvent et développent les vues de ces chercheurs qui croient que les trois bactéries seraient à considérer comme espèces séparées.
Paper read to the Pathology Section of the Second Triennial Conference of the European Association for Potato Research, Italy, September 1963. 相似文献
8.
Analysis of genomic mutation and immunohistochemistry of platelet‐derived growth factor receptors in canine vascular tumours
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S. Abou Asa T. Mori K. Maruo A. Khater A. El‐sawak E. Abd el‐Aziz T. Yanai H. Sakai 《Veterinary and comparative oncology》2015,13(3):237-245
We examined whether mutation of the platelet‐derived growth factor receptor protein tyrosine kinase (PDGFR)‐α and PDGFR‐β genes contributes to their overexpression in canine vascular tumours. Genomic sequences of trans‐ or juxtamembrane regions of PDGFR‐α and PDGFR‐β were analysed with immunohistochemical staining and polymerase chain reaction‐direct sequencing using DNA from paraffin‐embedded neoplastic tissues of 27 hemangiosarcomas (HSAs) and 20 hemangiomas (HAs). Immunohistochemically, 75% of the HA cases were positive for PDGFR‐α and almost most of the HA cases were negative for PDGFR‐β. Of the HSA cases, 55.6% were negative for PDGFR‐α and 63% were strongly positive for PDGFR‐β. Among the HA cases, 1 missense mutation was detected in PDGFR‐α exon 18 and 1 in PDGFR‐β exon 17. Two HSA cases had missense mutations in exon 14 and 1 in exon 17 of PDGFR‐β. Thus, genomic mutation of trans‐ or juxtamembrane regions of PDGFRs was not the main mechanism driving the activation of receptors in HSA and HA. 相似文献
9.
10.
The application of soil amendments to immobilize heavy metals is a promising technology to meet the requirements for environmentally sound and cost‐effective remediation. The present study was carried out to evaluate the result of phosphogypsum (PG) used alone and in combination with compost (CP) at a mix ratio of 1:1 wet weight ratio (PG + CP) at 10 and 20 g dry weight kg−1 dry soil, on heavy metal immobilization in contaminated soil and on canola growth. The results revealed that the Pb, Cd and Zn uptake of canola plants was reduced by the application of PG alone and when it was mixed with CP as compared with untreated soil. At an application rate of 10 g dry weight kg−1 dry soil of (PG + CP) the dry weight of canola plants increased by 66·8% was increased in comparison with its weight in the untreated soil. The addition of PG alone resulted in more pronounced immobilization of heavy metal as compared with PG mixed with CP. Plant growth was improved with CP addition, but heavy metals immobilization was the greatest in PG alone treatments. Results suggest that PG may be useful for the immobilization of heavy metals in contaminated soils. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献