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51.
Farag Sallabi Moustafa FadelAhmed Hussein Ahmad JaffarHazem El Khatib 《Computers and Electronics in Agriculture》2011,76(1):28-37
Documentation is a major component of any traceability system where traceability is defined in the ISO Regulation 8402:1994 as the ability to trace the history, application and location of what is under consideration. Traceability systems are record keeping systems designed to track the flow of product or product attributes through the production process or supply chain. All international supply chains are forced to comply with traceability requirements. In this paper, we develop and implement an end-to-end mobile application prototype that traces the poultry production. This application consists of front-end and back-end systems. At the front-end, the worker uses a GPRS enabled handheld device (cell phone, PDA, etc.) to capture information on poultry operations collected at a remote chicken farm and transmit it to a back-end server in the main office. Through customized application the back-end server analyses all information received from the front-end and based on a built-in business process and business rules, intelligently updates various stakeholders of any breach of bio-security measures that requires immediate attention. The proposed system administrators can also access this application via Internet for management decision making. The back-end system consists of web server, defined business application logic and database server. 相似文献
52.
A. E. A. El Sherbeiny N. A. M. Saleh H. I. El Sissi 《Plant foods for human nutrition (Dordrecht, Netherlands)》1971,20(4):297-309
This study is a continuation of the previous parts and also deals with the colour tests, free sugars and phenolic aglycones of thirty four plants, ranging from the familyMoraceae toRosaceae, with the aim of identifying the type of tannins present.
Zusammenfassung Diese Arbeit ist eine Weiterführung der vorangegangenen Mitteilungen und befaßt sich ebenfalls mit Farbreaktionen, freien Zuckern und phenolischen Aglykonen von weiteren 34 Pflanzen (Morraceae bis Rosaceae) mit dem Ziel, den Typ des jeweils vorliegenden Tannins zu identifizieren.
Resume Suite du travail précédent. Réactions colorées, sucres libres, aglycones phénoliques de 34 autres espèces végétales (Moracées à Rosacées). Essai d'identification des tannins présents dans chaque échantillon.相似文献
53.
N. A. M. Saleh A. E. A. El Sherbeiny H. I. El Sissi 《Plant foods for human nutrition (Dordrecht, Netherlands)》1969,17(4):384-394
Continuing a previous study, the leaves and barks of thirty one plants collected from the botanical gardens in Cairo, were subjected to detailed studies with the aim of identifying the type of tannins present in each plant. The study included colour tests and paper chromatography of both the free sugars and phenolic aglycones. The plants recorded here are those ranging fromAceraceae toFlacourtiaceae.
Zusammenfassung In Fortsetzung dieser Reihe wurden die Blätter- und Rindermaterialien von 31 Pflanzen, gesammelt aus den botanischen Gärten in Kairo, auf ihre Gerbstoffe untersucht. Mit Hilfe der Papierchromatographie wurden sowohl die freien Zucker als auch die phenolischen Komponenten dieser Pflanzen identifiziert.In dieser Mitteilung wurden die Untersuchungsergebnisse der Pflanzen der Familien Aceraceae bis Flacourtiaceae gegeben.
Résumé En poursuivant nos études précédentes, les feuilles et les écorses de 31 plantes cueillies dans les jardins de Caire, ont été soumises à des études détaillées. En vue d'identifier le type des tannins présent dans chaque plante, les études contenaient des expériments par chromatographie sur papier concernant les sucres natifs et les aglycones phénoliques. Les plantes qui ont été rapportées ici sont celles des familles Aceraceae à Flacourtiaceae.相似文献
54.
Since the presence of pest species on cultural plants does not mean always a real economical loss, crop loss assessment is to be considered the first step towards developing integrated control in vegetable crops. In our field-experiments there was no difference in the yield between treated and untreated cauliflowers or cabbage, inspite of a considerable attack ofErioischia brassicae Bouché in the area. Also the application of a herbicide (Aretit) to pea-culture did not increase the yield. Establishing the ‘economic threshold’ for potential pests is illustrated on the Cabbage maggot fly inBrassicas, and weeds in pea-culture. Different ways of helping to reduce the population density of a definite pest species were discussed: choosing the most adequate cultivation site, sanitary measures, intercrop relationships, using resistant crop varietes, choice and application of fertilizers. Biological control measures promise a good possibility:Aleochara-release againstE. brassicae in the UdSSR, sterile-male-technique against the onion fly in the Netherlands. Properties of pesticides allowed in integrated control programmes were discussed with examples: Non-persistance, high selectivity, accumulation-danger from previous crops etc. Lastly some problems caused by incorrect interpretation of the expression ‘integrated control’ as well as the possible limits of the procedure were discussed. 相似文献
55.
C. El Modafar A. Clérivet A. Vigouroux J. J. Macheix 《European journal of plant pathology / European Foundation for Plant Pathology》1995,101(5):503-509
Inoculation of leaves of resistantPlatanus occidentalis and susceptiblePlatanus acerifolia leaves withCeratocystis fimbriata f. sp.platani, the canker stain disease agent, induced foliar necrosis and biosynthesis of two phytoalexins, scopoletin and umbelliferone. Foliar symptoms keep localized and accumulation of coumarin phytoalexins was rapid for incompatible interactions. Necrosis spread widely and accumulation of these phenolic compounds was much later and lower for compatible interactions. The differential response could be used in a genetic improvement program for resistance against canker stain. 相似文献
56.
A. F. Ibrahim A. N. Sharaan A. W. El Wakil 《Journal of Agronomy and Crop Science》1991,167(3):170-175
Two promising selected land races of safflower ( Carthamns tinctorious L.) designated as line 11 and line 13, together with the local variety Giza 1 , were examined under three levels of moisture depletions, i.e. 40, 60 and 80 % ASMD at Fayoum, Middle Egypt during 1986/87 and 1987/88 seasons. In both growing seasons, the second irrigation treatment i.e. 60 % ASMD gave the highest means for growth characters as well as seed yield and most of its components. Seed oil content per cent exhibited an increased as soil moisture depletion increased with no significant difference between entries. Safflower entries showed clear differences in some yield components which compensate each other and resulted in no significant difference in seed yield per hectar.
Consumptive use of water by safflower plants increased as the available soil moisture around the root zone increased. No significant differences were found in water consumed by safflower entries used in all experiments.
In the two experimental seasons, the best water use efficiency (WUE) for seed production was obtained also from the second treatment (60 % ASMD). The line 11 gave the best WUE. 相似文献
Consumptive use of water by safflower plants increased as the available soil moisture around the root zone increased. No significant differences were found in water consumed by safflower entries used in all experiments.
In the two experimental seasons, the best water use efficiency (WUE) for seed production was obtained also from the second treatment (60 % ASMD). The line 11 gave the best WUE. 相似文献
57.
58.
An approach for precision farming under pivot irrigation system using remote sensing and GIS techniques 总被引:1,自引:0,他引:1
The current work is aimed to realizing land and water use efficiency and determining the profitability of precision farming economically and environmentally. The studied area is represented by an experimental pivot irrigation field cultivated with maize in Ismailia province, Egypt. Two field practices were carried out during the successive summer growing seasons (2008 and 2009) to study the response of maize plants single hybrid 10 (S.H.10) to traditional and precision farming practices. Traditional farming (TF) as handled by the farm workers were observed and noted carefully. On the other hand precision farming (PF) practices included field scouting, grid soil sampling, variable rate technology and its applications. After applying PF a dramatic change in management zones was noticed and three management zones (of total four) were merged to be more homogenous representing 84.3% of the pivot irrigation field.Under PF Remote Sensing and Geographic Information System techniques have played a vital role in the variable rate applications that were defined due to management zones requirements. Fertilizers were added in variable rates, so that rationalization of fertilizers saved 23.566 tonnes/experimental pivot area. Natural drainage system was improved by designing vertical holes to break down massive soil layers and to leach excessive salts. Crop water requirements were determined in variable rate according to the actual plant requirements using SEBAL model with the aid of FAO Cropwat model. Irrigation schedule of maize was adopted considering soil water retention, depletion, gross and net irrigation saving an amount of water equal to 93,718 m3 in the pivot irrigation field (153.79 acre). However costs of applying PF were much higher than TF, the economic profitability (returns-costs) achieved remarkable increase of 29.89% as a result of crop yield increment by 1000, 2100, 800 and 200 kg/acre in the management zones 1, 2, 3 and 4, respectively. Finally applying adequate amounts of fertilizers beside water control the environmental hazards was reduced to the acceptable limits. 相似文献
59.
This investigation was carried out to determine the variability in oil content with the aim to identify genotypes of argan tree expressing high oil yield. The 150 argan trees were collected from five provenances in south west of Morocco over 3 years (2008–2010) and were screened from their oil content using Soxhlet method based on the 840 samples. Univariate and multivariate analysis were used to study the genetic variation between and within provenances. According to the results on the mean of the 3 years, the oil content was ranged from 38.45 to 62.54 %. The genotypes from Aoulouz and Had Dra expressing high oil yield. Variance components for fruit, seed, kernel traits and oil content showed significant differences (P < 0.01) among years, provenances, genotypes and their interaction. Principal component analysis proved that fruit, seed, kernel, weight traits are correlated with oil content and are discriminate characters between the genotypes. The results of the cluster analysis support the results of the principal component analysis, showing no correlation between oil content with geographical localization parameters. For all the promising genotypes, at least 25 % were found to be better and exceed the oil mean of the provenance for 3 years. So, 31 promising elite genotypes were preselected, and open new ways for future comparative test of them in diverse environments. 相似文献
60.
Zusammenfassung Seit zehn Jahren betreibt der Lel-irstuhl für Waldbau and Forsternrichtung der Universit?t M?nchen intensive Verjüngungsstudien
auf 25 Dauerversuchsfl?chen im Bergmischwald der ostbayerischen Kalkalpen. Am Bei-spiel der Aufnahmedaten yon fünf ausgew?hlten
Versuchsfl?chen werden grundlegende Prinzipien des Ver-jüngungsprozesses im Bergmischwald aufgezeigt and daraus praktische
Konsequznzen abgeleitet.
Alle am Autbau der Altbest?nde des Bergmischwaldes beteiligten Baumarten bilden bislang trotz d utli-cher Waldschadenssvmptome
reichlich Samen von hochwertiger Qualit?t aus.
Damit aus diesem Verjüngungspotential Naturverjüngung entstchen kann, müssen die en tsprechenden überschirmungsverh?ltnisse
lurch den Altbestand gegeben sein. Für die Dichte, Baumartenztusammenset zung and H?henentwicklung der Naturverjüngungspflanzen
ist n?mlich die Uberschirrnung von ganz ent-scheidender Bedeutung. In einem sehr dichten Altbestand, in derv der überschirmungsgrad
fiber 75% liegt , haben Verjüngungspflanzen Schwierigkeiten, sick zu etablieren. Eine Ieichte Auflichtung auf einen über-schirmungsgrad
von 60 (der dann gegeben ist, wenn die rich unter dem Schirm entwickelnde Bodenvege cation Bedeckungsgrade zwischen 20 and
3C einstellt) erm?glicht den Naturverjüngungsflanzen ein überleben. Diese Uberschirmung kann durch einen schwachen Schirmhieb
(Entnahme von etwa einem Vier-tel der Grundtl?che eines geschlossenen Bestandes) erreicht werden. Diese Eingriffsst?rke dürfte
auch unter den Gesichtspunkten der Stabilit?it and des Zuwachsverlustes dill Altbestand zu vertreten sein.
Vor einer st?rkeren Auflichtung des Altbestandes müsses genügend Naturverjüingungspflanztn ant Bo den vorhanden sein. Nur
so is[ gew?hrleistet, daβ these einen Vorsprung vor der Bodenvegatation bekom Men.
Die Pflanzung ist immer dann, wenn sich Schwierrigkeiten mit der Naturverjüngung ergeben, ein geeigne-tes Mittel, um einen
neuen Bergmischwald zu begründen.
Derzeit ist für das Entstehen tines neuen Bergmischwaldes - sei es durch Naturverjüngung odor lurch Pflanzung - Zaunschutz
erforderlich.
Summary In 1976, a research project entitled ’Natural Regeneration of Mixed Mountain Forests ’ was etablished in the Calcareous Alps
of eastern Bavaria, by the Chair of Silviculture and Forest Management of the University Of Munich. Over the past ten years,
the multi-variate aspects of regenaration have bean intensively investigated on 25 permanent research plots. The data from
5 selected plats were extracted and processed. from these data, it will be possible to present some fundamental principles
of natural regenaration processes. From these prin-ciples, it is hoped that some practical applications can be derived.
The mature stands of mixed mountain forests are still able to produce high quantities and good quality of seed, although distinct
symptoms of forest decline are present.
In order to utilize this potential for natural regeneration, an adequate canopy density is necessary. Canopy density is the
crucial factor which regulates the density, species composition and height development of regeneration. In a very heavily,
stocked mature stand with a canopy density of over 75 establishment of regenerations is difficult. When canopy density is
reduced to, for example, 60% (this percentage can be estimated from a ground vegetation covering approximately 20–30 of the
soil), the naturally regenerated, plants have a better opportunity to survive. A 60% canopy density can be achieved by light
shelterwood cutting (removal of approximately 25% of basal area of a closed stand). This type of cutting can maintain the
stability and prevent increment loss of forest stands. It is important that regeneration is established before opening up
the stand, only, then these plants are capable to compete with the other ground vegetation.
Planting is always appropriate when natural regeneration fails.
Fencing is necessary for undisturbed development of natural and artificial regeneration.
Dieses Heft enth?lt waldbauliche Beitr?g zu den Forschungsschwerpunkten Bergwald, Waldschaden und Kiefer. Sie sind überwiegen als Vortr?ge auf der Hochschulwoche der Forstwissenschaftlichen Fakult?t München im Oktober 1987 gehalten worden. Ihre Autoren widmen sie Herrn Professor Dr. Peter Burschel zum 60. Geburtstag.
Auf der Forstlichen Hochschulwoche 1987 in München gehaltener Vortrag. 相似文献
Dieses Heft enth?lt waldbauliche Beitr?g zu den Forschungsschwerpunkten Bergwald, Waldschaden und Kiefer. Sie sind überwiegen als Vortr?ge auf der Hochschulwoche der Forstwissenschaftlichen Fakult?t München im Oktober 1987 gehalten worden. Ihre Autoren widmen sie Herrn Professor Dr. Peter Burschel zum 60. Geburtstag.
Auf der Forstlichen Hochschulwoche 1987 in München gehaltener Vortrag. 相似文献