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1.
The biomonitoring program of Environment Canada examines food chains in small Ontario lakes to interpret ecological responses of waterfowl and their foods to changing acid deposition. Macroinvertebrates and fish were sampled in three acid-sensitive regions: Muskoka (1991; N=20), Algoma (1992; N=20), and Sudbury (1994; N=22). Small lakes (<11 ha;=" important=" breeding=" habitat=" for=" waterfowl)=" were=" chosen=" to=" cover=" the=" range=" of=" ph=" in=" each=" region,=" and=" include=" those=" with=" and=" without=" fish.=" in=" all=" regions,=" macroinvertebrate=" taxonomic=" richness=" (particularly=" nekton=" and=" benthos)=" was=" greater=" in=" fishless=" lakes=" compared=" to=" lakes=" with=" fish.=" among=" fishless=" lakes,=" taxonomic=" richness=" (especially=" benthos)=" was=" positively=" correlated=" with=" ph,=" although=" regional=" differences=" were=" evident.=" previous=" studies=" near=" sudbury=" have=" shown=" that=" several=" benthic=" groups=" have=" distribution=" and=" abundance=" patterns=" with=" respect=" to=" ph=" (trichoptera,=" ephemeroptera,=" hirudinea,=" amphipoda,=" and=" gastropoda).=" those=" patterns=" continue=" near=" sudbury,=" and=" were=" also=" strongly=" apparent=" in=" algoma.=" in=" all=" regions,=" the=" number=" of=" acid-sensitive=" taxa=" per=" lake=" is=" related=" to=" ph,=" and=" should=" increase=" as=" lakes=" recover=" from=" acidification.=" however,=" predicting=" macroinvertebrate=" responses=" to=" recovery=" must=" consider=" concurrent=" effects=" of=" fish,=" as=" they=" are=" a=" dominant=" factor=" structuring=" these=">  相似文献   

2.
Acid clearwater fishless streams have been identified in the Vosges mountains. In order to evaluate the relatipnships between acidifying factors (such as atmospheric deposition), buffering factors (such as bedrock and soil type), and surface water acidity, an exhaustive survey of streamwater acidity in the Vosges mountains (N-E France) was performed. A network of 11 measurement stations of atmospheric deposition was used to estimate and map deposition over the whole massif (total area 5000 km2). Data on bedrock, soil, superficial deposits, and vegetation were collected from published studies. Sensitive areas as well as acidifying environment factors were derived from the corresponding maps. Over the whole massif, 19% of streams showed baseflow alkalinity below 30 eq.r1 and 7.5 % were identified as acid (pH < 5.4).=" acid=" streams=" occur=" on=" the=" north-western=" side=" of=" the=" massif=" on=" quartzrich=" sandstone=" and=" acid=" granites.=" in=" each=" of=" these=" areas,=" we=" could=" clearly=" point=" out=" on=" one=" hand,=" the=" negative=" influence=" of=" conifer=" vegetation=" and=" glacial=" soil=" abrasion=" or=" induration,=" and=" on=" the=" other=" hand=" the=" buffering=" effect=" of=" moraine=" deposits.=" a=" corresponding=" range=" of=" critical=" loads=">< 0.2=" to=" 2.0=" keq.=">1 yr1) for surface water was calculated using the Steady State Water, Chemistry method (SSWC).  相似文献   

3.
Bulk snow samples were collected from the snowpack in open areas along two sampling lines running to the west from the Cu-Ni smelters at Nikel and Monchegorsk, NW Russia, during 1991–1993. The aim of the study was to estimate the area affected by sulphur and heavy metal deposition from the smelters. Snowpack quality was used as an indicator of deposition during winter time. The total sulphur, copper and nickel concentrations in the snowpack decreased significantly (p<0.001) with=" increasing=" distance=" from=" the=" smelters=" along=" the=" sampling=" line=" running=" directly=" to=" the=" west=" from=" monchegorsk.=" the=" deposition=" pattern=" was=" similar=" each=" winter=" during=" 1991–1993.=" the=" ph=" values=" did=" not=" correlate=" with=" the=" corresponding=" sulphur=" concentrations,=" and=" there=" was=" no=" decreasing=" ph=" gradient=" in=" the=" snowpack=" on=" moving=" towards=" monchegorsk.=" the=" effects=" of=" sulphur=" emissions=" from=" monchegorsk=" on=" snowpack=" chemistry=" were=" not=" detectable=" on=" the=" finnish=" side=" of=" the=" border.=" the=" 3-year=" mean=" of=" the=" total=" sulphur=" concentration=" was=" 0.27=" mg/kg,=" and=" of=" the=" ph=" values=" 4.92,=" along=" the=" sampling=" line=" running=" to=" the=" west=" of=" monchegorsk.=" the=" total=" sulphur=" concentrations=" near=" the=" smelters=">< 20=" km)=" varied=" between=" 0.37=" and=" 0.95=" mg/kg.=" the=" effect=" of=" the=" cu-ni=" smelters=" at=" nikel=" on=" snowpack=" quality=" was=" not=" detectable=" in=" northern=" finnish=" lapland.=" the=" 3-year=" mean=" for=" total=" sulphur=" was=" 0.20=" mg/kg=" and=" for=" ph=" 4.96=" along=" the=" sampling=" line=" running=" to=" the=" west=" of=">  相似文献   

4.
Zusammenfassung Die Messung von Absorptionsspektren biologischer Objekte in vivo ermöglicht eine rasche Information über die Zusammensetzung und den Zustand der enthaltenen Pigmente, insbesondere bei der Untersuchung photosynthetisch aktiver Organe. Es wird deshalb eine Übersicht über Probleme, Methoden und Anwendungsmöglichkeiten gegeben.Meßtechnische Schwierigkeiten ergeben sich in erster Linie aus der Lichtstreuung, die in verschiedener Weise zu einer Verzerrung der Spektren führt. Eine Verringerung dieser Effekte ist mit verschiedenen Methoden möglich, die entweder das Streulicht oder einen repräsentativen Anteil desselben sammeln oder durch Angleichung des Brechungsindex des umgebenden Mediums die Streuung selbst herabsetzen.Das Auftreten verschiedener Pigmentformen mit ähnlichen spektralen Eigenschaften führt zu einer starken Überlagerung und damit schlechter Auflösung ihrer Absorptionsbanden. Eine Erhöhung der Auflösung ist mit Methoden möglich, die die Halbwertsbreite der Banden verringern. Dazu dienen die Messung bei der Temperatur des flüssigen Stickstoffs (–196 °C) und die Anwendung mathematischer Verfahren zur Bandenverschärfung, insbesondere der Derivativ-Spektrophotometrie.Einige Anwendungsbeispiele demonstrieren den Nutzen der Methode bei der Untersuchung der Chlorophylle in vivo.
Measurement of absorption spectra in vivo
Summary The measurement of absorption spectra of biological objects enables fast information about composition and state of pigments, especially in the study of photosynthetically active organs. Therefore a review is given about problems, methods, and possible applications.Difficulties in the measurement result mainly from light scattering, causing a distortion of spectra in different ways. A reduction of these effects is possible by several methods, which either collect the scattered radiation (or a representative portion of it) or decrease the scattering by adjusting the refractive index of the surrounding medium to those of the cell walls.The existence of different pigment forms having similar spectral properties results in a strong overlapping and bad resolution of their absorption bands. A resolution enhancement is possible by methods reducing the halfwidth of the bands. This can be performed by measurement at liquid nitrogen temperature (–196 °C) and by mathematical methods of band sharpening, especially derivative spectrophotometry.Some examples demonstrate the use of the method in the study of chlorophylls in vivo.

in vivo
in vivo , . , . , , , . , ( ) , , . , , . . (– 196 °C) , — . in vivo.


Herrn Prof. Drs. Dr. h. c.Hans Stubbe zum 75. Geburtstag gewidmet.  相似文献   

5.
An extensive database from eight Triassic (Bunter) sandstone catchments in the Black Forest, SW Germany, was used to apply the MAGIC model and simulate long-term acidification trends. Using the ion ratio (Ca+Mg)/(SO4+NO3) as criterium (values< 1.5=" indicate=" an=" acidified=" state),=" hindcast=" simulations=" showed=" that=" the=" brooks=" of=" three=" catchments=" have=" reached=" values="><1.5, three=" catchments=" are=" approaching=" 1.5,=" and=" two=" catchments=" (carbonate=" bearing=" upper=" bunter)=" are=" still=" well=" above=" this=" limit.=" the=" different=" acidification=" state=" of=" the=" catchments=" is=" mainly=" caused=" by=" the=" amount=" of=" acidic=" deposition=" and=" bedrock=" geology.=" other=" differences=" (shallow=" or=" deep=" groundwater=" circulation,=" sulphate=" sorption=" and=" soil=" parameters)=" are=" less=" significant.=" to=" simulate=" the=" future=" evolution,=" three=" scenarios=" were=" tested:=" a=" pessimistic,=" an=" optimistic=" and=" a=" most=" probable=" case.=" the=" latter=" leads=" to=" a=" still=" progressing=" but=" decelerated=" acidifcation=" in=" the=" next=" 100=" years.=" in=" the=" pessimistic=" case,=" acidification=" rates=" will=" be=" accelerated=" in=" two=" of=" the=" catchments.=" even=" in=" the=" optimistic=" case,=" the=" initial=" state,=" prior=" to=" acidification,=" cannot=" be=" restored=" up=" to=" the=" year=" 2130.=" however,=" the=" forecasting=" of=" the=" future=" evolution=" is=" still=" markedly=" hampered=" by=" the=" significant=" uncertainty=" in=" the=" evaluation=" of=" nitrogen-driven=" acidification,=" a=" process=" which=" today=" already=" predominates=" in=" parts=" of=" the=" black=">  相似文献   

6.
The objective of this study was to investigate Cd bioaccumulation in clams living in different salinities. Several hundred clams (Maritrix maritrix) and sediment samples were collected during 1985–1986 from 12 locations on the Saudi coastal areas of the Arabian Gulf. Soft tissue from each clam was removed and digested in HNO3. Sediments were also digested in HNO3. Cadmium in the recently collected seawater samples was extracted using pyrrolidine carbodithioic acid-chloroform system. Cadmium in all the collected samples was determined using an inductively coupled argon plasma analyzer. Concentrations of Cd in the sediments varied insignificantly between 0.1 and 0.22 mg kg–1. Significant geographical variations in the mean Cd concentrations in clams (P < 0.05)=" were=" found.=" intrastation=" differences=" in=" cd=" bioaccumulation=" were=" also=" significant.=" correlation=" between=" biometric=" observations=" and=" cd=" concentrations=" in=" clams=" was=" not=" significant=" (p=">< 0.05).=" seawater=" salinity=" was=" significantly=" (p=">< 0.05)=" correlated=" to=" the=" mean=" cd=" concentrations=" in=" clams=" and=" seawater.=" cadmium=" accumulation=" in=" the=" clams=" was=" supported=" by=" the=" chemical=" behavior=" of=" cd=" in=">  相似文献   

7.
Summary The effects of Cd, Co, Ni and Zn on growth and survival of Macrophomina phaseolina were studied in vitro. Cd, Ni and Co at 500 g ml–1 inhibited growth by 78.8%, 73.6% and 11.8%, respectively, after 4 days at 25 ± 1°C. The mycelial dry weight yield was enhanced by 2.1% at 100 g ml–1 Zn. The population of the pathogen declined in soil amended separately with Cd, Co, Ni and Zn. Cd (4000 mg kg–1) proved to be the most toxic, by completely inhibiting the survival of the pathogen in soil after 20 days.  相似文献   

8.
Rainwater was collected at the campus of the University of Brunei Darussalam in Bandar Seri Begawan, Brunei Darussalam, using a funnel-in-bottle sampler. Polypropylene bottles were changed at intervals during rainstorm events. The pH and conductivity were determined immediately after collection on aliquots of the sample. Samples were refrigerated at 5°C for subsequent chemical analysis. Analyses for Na, Mg, Ca, Zn and Fe were carried out by means of inductively coupled plasma atomic emission spectroscopy (ICP-AES); Cu and Mn were analysed by graphite furnace atomic absorption spectroscopy (GFAAS); K was analysed using flame atomic emission spectroscopy (FAES); and Cl, NO3 and SO4 2– were analysed by ion chromatography (IC). Concentration versus time profiles are reported for three rainstorm events. All ions exhibited a decrease in concentration during the rainstorm. The first sample contained the highest concentration of ions, consistent with a first-flush effect. The contribution of the initial stages of the shower to the total quantity of ion deposited during the entire rainstorm is quite overwhelming; in many cases 20 to 30% of the mass was deposited in less than 5% of rainstorm duration. On the other hand, the pH and conductivity variation during rainstorms did not exhibit a consistent pattern.  相似文献   

9.
A spatial and temporal investigation of dissolved inorganic nitrogen (DIN; NO3, NO2 and NH4) was conducted under various water discharge conditions in Lanyang-Hsi, a subtropical mountainous stream, which drains through distinct degrees of agriculture-influenced sub-watersheds. In both the cultivated and non-cultivated sub-watersheds, NO3 was the most abundant species accounting for >80% of total DIN, while NH4 and NO2 accounted for <15% and=" 5%=" of=" din,=" respectively.=" agricultural=" activities=" along=" the=" riverbank=" led=" to=" significantly=" higher=">3 concentrations (13–246 M) and DIN yields (1300–3800 kg N km–2 yr–1) in main channel when compared to those of non-cultivated tributaries (9–38 M for NO3 and 550–740 kg N km–2 yr–1 for yield). The much lower and less variable DIN yields observed in tributary stations (mean = 660 ± 120 kg N km–2 yr–1) are considered as the present day background of DIN yield, which is significantly higher than those of most natural watersheds in other regions. Elevated atmospheric DIN deposition is likely the cause for the high background DIN yield. Human activity within the watershed results in additional DIN yield, which accounted for 49% of total N export. However, the reported atmospheric DIN input in northern Taiwan (1800 kg N km–2 yr–1) is much higher than the background DIN yield implying that a major fraction (70%) of atmospheric inputs are retained or processed within the watershed. A dilution pattern occurred in the main channel where high NO3 concentrations from the upstream sources decreased significantly in downstream direction due to inputs of NO3-diluted water from non-cultivated areas. We adopted a two-source mixing model to predict the NO3 dilution pattern. This model revealed a third yet not recognized N source in the lower part of watershed. Model results also indicated the importance of water discharge rate in regulating the relative contribution to total DIN export among these sources.  相似文献   

10.
Condition factor, K, was measured for 1202 blacknose dace (Rhinichthys atratulus) from three streams in Shenandoah National Park (USA) of different acid neutralizing capacities (ANCs). K is a ratio of weight standardized to length; it is an indication of the health of the individuals in a population. R. atratulus condition factor in the low-ANC stream was found to be significantly lower (11%) than that of dace measured for fish from the intermediate- and high-ANC streams. This difference, according to the results of related investigations, is likely to be biologically significant. Whole-body sodium concentrations were measured as an additional test of sublethal stress in these streams. During summer base flow conditions, mean whole-body sodium concentrations of adult R. atratulus maintained in cages were found to be highest in the low-ANC stream and lowest in the high-ANC stream. The lower condition factor of dace in the low-ANC stream may be related to whole-body sodium concentration and ion regulation. Ion regulation in the low-ANC stream may be more metabolically costly because of chronic sublethal pH stress. R. atratulus may maintain high body Na+ concentrations in low ANC- and ionic strength waters in order to provide a buffer against large episodic pH depressions. The metabolic cost of this ionoregulatory over-compensation may necessitate the diversion of energy from somatic growth and explain the poorer condition of fish from such waters.  相似文献   

11.
High-elevation red spruce-Fraser fir forests in the Southern Appalachian mountains: 1) receive among the highest rates of atmospheric deposition measured in North America, 2) contain old-growth forests, 3) have shown declines in forest health, 4) have sustained high insect-caused fir mortality, and 5) contain poorly buffered soils and stream systems. High rates of nitrogen and sulphur deposition (1900 and 2200 Eq·ha–1·yr–1, respectively) are dominated by dry and cloud deposition processes. Large leaching fluxes of nitrate-nitrogen (100–1400 Eq·ha–1·yr–1) occur within the soil profile. We have expanded the study to the watershed scale with monitoring of: precipitation, throughfall, stream hydrology, and stream chemistry. Two streamlets drain the 17.4 ha Noland Divide Watershed (1676–1920m) located in the Great Smoky Mountains National Park. A network of 50 20x20 m plots is being used to assess stand structure, biomass, and soil nutrient pools. Nitrate is the predominant anion in the streamlets (weighted concentrations: 47 and 54 eq·L–1 NO3 ; 31 and 43 eq·L–1 SO4 2–). Watershed nitrate export is extremely high (1000 Eq·ha–1 yr–1), facilitating significant base cation exports. Stream acid neutralizing capacity values are extremely low (–10 to 20 eq·L–1) and episodic acidifications (pH declines of a full unit in days or weeks time) occur. Annual streamwater sulfate export is on the order of 770 Eq·ha–1yr–1 or about one-third of total annual inputs, indicating there is net watershed sulfate retention. The system is highly nitrogen saturated (Stage 2, Stoddard, 1994) and this condition promotes both chronic and episodic stream acidification.  相似文献   

12.
Recolonization of soils by organisms is dependent not only on biological factors but also on site factors including soil and vegetation. The total nematode populations in soil sterilized 52 months earlier with methyl bromide ranged from 77 to 123% of those in untreated soil; both vegetation and rainfall appear to have been important factors in the recolonization. In a high-rainfall pasture the dominant plant-feeding nematode Helicotylenchus did not recolonize and was replaced by Paratylenchus. Under high rainfall, Iotonchus failed to recolonize either pasture or forest, but Clarkus recolonized well. While indices such as the maturity index, the summed maturity index, PPI, the ratio of fungal: bacterial feeding nematodes, species richness, the Shannon-Weaver index, and indices of evenness, dominance, and diversity showed various effects, none gave consistent trends; rainfall and vegetation probably exerted too much influence. In the light of trends in our data, in data for other ecosystems, and the reality of r-K strategies in animals, it may not be reasonable to expect a global nematode index of soil health or ecosystem condition. While a nematode index may be useful in local or regional studies, research efforts may be better directed towards elucidating key populations of nematodes for investigating the impact of particular land management practices on ecosystem sustainability.  相似文献   

13.
Summary The variability of 19 seed characters has been examined for 52 species of the genusVicia. Seed circumference, relative hilum length, hilum shape and lens position could be confirmed as the most relevant characters for grouping. By cluster analyses based upon them the material has been classified into 11 groups. Discriminant analyses gave 25 % misclassifications when all 19 variables were subjected to the analysis for the determination of individual seeds. A key for determination of the species has been proposed mainly by means of quantitative seed characters; dendrograms illustrate the result of the cluster analyses and seed diagrams show schematically important seed characters.
Die Variabilität von Samenmerkmalen bei ausgewähltenVicia-Arten
Zusammenfassung Es wurde die Variabilität von 19 Samenmerkmalen bei 52 Arten der GattungVicia geprüft. Für eine Gruppenbildung bestätigten sich dabei der Samenumfang, die relative Nabellänge, die Nabelform und die Lage der Chalaza als besonders geeignet. Bei einer auf diesen Merkmalen aufbauenden Cluster-Analyse konnten innerhalb des Untersuchungsmaterials 11 Artengruppen ausgeschieden werden. Diskriminanz-Analysen unter Verwendung von allen 19 Variablen ergaben eine Fehlklassifikation beim Versuch der Zuordnung einzelner Samen in 25 % der Fälle. Ein Schlüssel zum Bestimmen der Arten vorzugsweise an Hand von quantitativen Samenmerkmalen wurde vorgeschlagen. Dendrogramme illustrieren die Ergebnisse der Cluster-Analysen und schematische Samendiagramme die Ausprägung der relevanten Samenmerkmale.

Vicia
19 52 Vicia. : , , . , , 11 . , 19 25 % . , . , — .
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14.
Zusammenfassung Die ursprüngliche Naumburger Malus-Artenkollektion wurde in das Institut für Obstforschung Dresden-Pillnitz überführt. Sie umfaßt 237 Arten und Varietäten und damit die wichtigsten Vertreter der 5 Sektionen vonMalus - Malus, Sorbomalus, Chloromeles, Eriobolus, Docyniopsis (nachRehder 1954). Die bereits vorliegenden Untersuchungsergebnisse an dieser Kollektion über Pollenfertilität, Apomixis, Schorf-, Mehltau- und Blutlausresistenz sowie Virustoleranz werden mitgeteilt.Auf die nationale und internationale Bedeutung dieses Genfonds, der für den Austausch zur Verfügung steht, wird hingewiesen.
Genetic resources ofMalus in the GDR and their utilization
Summary The collection ofMalus germplasm originally located in Naumburg has been transfered to the Institute of Fruit Research in Dresden-Pillnitz. It contains 237 species and forms and therewith important representatives of the 5 sections ofMalus - Malus, Sorbomalus, Chloromeles, Eriobolus, Docyniopsis (according toRehder 1954). The results already obtained on the basis of this germplasm concerning pollen fertility, apomixis, resistance to scab, mildew, woolly aphid, and virus tolerance are presented here. The national and international importance of thisMalus collection which is available for distribution is stressed.

Malus
Malus, . , -. 237 :Malus, Sorbomalus, Chloromeles, Eriobolus, Docyniopsis ( , 1954). , , , , , , , . , , , .
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15.
Zusammenfassung Das während einer Reise in südliche Gebiete der VR Polen 1978 (vgl.Hanelt undSchultze-Motel 1979) gesammelte Kulturpflanzen-Material wird botanisch charakterisiert. Es handelt sich überwiegend um Landsorten und alte Sortentypen, die oft eine variable Zusammensetzung zeigen; ihr Anbau ist jedoch meist in raschem Rückgang begriffen. Charakteristische indigene Formen konnten u. a. beiTriticum aestivum, Secale cereale, Hordeum vulgare, Avena sativa, Vicia faba undPhaseolus vulgaris nachgewiesen werden. Besonders interessant sind zweiund mehrzeilige Nacktgersten, der hohe Anteil von Schüttmohnen innerhalb derPapaver-Kollektion, extrem kleinsamige, als Unkraut auftretende Formen vonPisum sativum convar.speciosum, der Nachweis eines reliktartigen Anbaues vonCamelina sativa sowie verschiedener, nur noch selten kultivierter Heilpflanzen. In morphologischer Hinsicht sehr variable Populationen von Landsorten wurden vor allem beiTriticum aestivum, Panicum miliaceum undPhaseolus vulgaris beobachtet. Die früher gegebene Einschätzung der südpolnischen Gebirgsregionen als Erhaltungsgebiet autochthoner Sippen von Kulturpflanzen konnte bestätigt werden; eine Fortführung der Sammeltätigkeit erscheint notwendig.
Catalogue of indigenous taxa of cultivated plants collected 1978 in the PR Poland
Summary The material of cultivated plants collected during a mission to southern regions of PR Poland in 1978 has been characterized botanically. It is represented mainly by land-races and old varieties which are often rather variable; their cultivation is mostly decreasing rapidly. Typical indigenous types could be discovered e.g. forTriticum aestivum, Secale cereale, Hordeum vulgare, Avena sativa, Vicia faba andPhaseolus vulgaris. Especially interesting are two- and six-rowed naked barleys, a high percentage of poppies with shattering capsules among thePapaver collection, extremely small-grained weedy strains ofPisum sativum convar.speciosum, the discovery of a relic cultivation ofCamelina sativa and of some seldom cultivated medicinal plants. Morphologically very variable populations of land-races have been observed especially inTriticum aestivum, Panicum miliaceum andPhaseolus vulgaris. The characterization of the mountainous regions of southern Poland already formerly stated as a refugial area of autochthonous taxa of cultivated plants could be confirmed; a continuation of the collecting work seems to be necessary.

, HP 1978
, 1978 HP (.Hanelt undSchultze-Motel 1979). , , ë , . , , Triticum aestivum, Secale cereale, Hordeum vulgar e, Avena saliva, Vicia faba PhaseoLus vulgaris. ë , (Pisum sativum convar.speciosum); Camelina sativa . Triticum aestivum, Panicum miliaceum, Phaseolus vulgaris. - , .


Herrn Prof. Dr. Dr. h. c. mult. H.Stubbe aus Anlaß der 80. Wiederkehr seines Geburtstages gewidmet.

Den Mitarbeitern der Genbank in Gatersleben sind wir für die bewährte Anzucht, Pflege und Bonitierung des Pflanzenmaterials zu großem Dank verpflichtet.An der Sammelreise beteiligten sich vom IHAR Radzikow ferner Mag. M.Górski, Mag. A.Jastrzbski und Ing. W.Doboszyski.  相似文献   

16.
Zusammenfassung Die Einrichtung einer Röntgentiefentherapieanlage für die Bestrahlung von Saatgut in der Strahlengenetik wird beschrieben. Für die Standardisierung der Bestrahlungsbedingungen werden Vorschläge unterbreitet.
Summary The setting up of an x-ray depth therapy equipment for the irradiation of plant seeds in the field of radiation genetics is described. For the standardization of irradiation conditions suggestions are presented.

, . .
  相似文献   

17.
Zusammenfassung Die Heimat vonHelianthus tuberosus L. dürfte Mexiko sein, von wo aus sich die Kultur entlang der Ostküste Nordamerikas ausbreitete und besonders von den Indianerstämmen im Bereich der Mündung des St. Lorenz-Stromes gepflegt wurde.Die Einführung nach Europa erfolgte über romanische Länder. Nach Frankreich kam die Art 1607 aus Nordamerika. Die Holländer übernahmen sie 1613 aus Frankreich. Für andere europäische Länder läßt sich nur das Jahr der ersten Nachweisbarkeit feststellen (Italien 1614, England 1617, Deutschland 1626, Dänemark 1642, Polen 1652, Schweden 1658, Portugal 1661). Die Ausbreitung der Pflanze wird in den Rahmen der europäischen Kulturgeschichte gestellt. Wichtigster Ausgangspunkt der Verbreitung war Frankreich. Die Pflanze war Wegbereiter für den Anbau vonSolanum tuberosum L., der von England während der Aufklärungszeit ausging. — Die Entstehung der in einzelnen Ländern verwendeten Vernakulärnamen wird erläutert.
Summary The native country ofHelianthus tuberosus L. might be Mexico, from where the cultivation has spread along the Eastern coast of Northern America; the crop was especially important for the Indian tribes in the region of St. Lawrence River's mouth. — The introduction to Europe has happened by way of Romanic countries. France got this species in 1607 from Northern America. From here it was introduced to the Netherlands in 1613. For other European countries it is only possible to fix the year of the first statement in the literature (Italy 1614, England 1617, Germany 1626, Denmark 1642, Poland 1652, Sweden 1658, Portugal 1661). It has been described the expansion of the plant, which has been compared with the history of European culture. The most important starting-point of the expansion of Jerusalem's artichoke has been France. The plant prepared well the cultivation of the Irish potato which began in England during the Age of Enlightenment. — The origin of the vernaculare names, used in different countries forH. tuberosus, has been explained.

,Helianthus tuberosus L., , . . . . . 1607 . 1613. : 1614, 1617, 1626, 1642, 1652, 1658, 1661. . , , . — , .
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18.
Zusammenfassung Die morphologischen, ökologischen, phänologischen und geographischen Unterschiede der in Mittel-Europa auftretenden blaublühenden Sippe vonLithospermum arvense L. gegenüber der weißblühenden Normalform werden herausgearbeitet und ihre bis jetzt bekannten Fundorte zusammengestellt. Die Sippe (var.coerulescens DC.), die möglicherweise einen höheren Rang verdient, nimmt innerhalb des Formenkreises der Art eine ursprüngliche Stellung ein, während die weitverbreitete weißblühende Unkrautsippe abgeleitet erscheint. Der im einzelnen noch ungenau bekannte Formenreichtum der Art ist im südrussischen und vorderasiatischen Raum am größten. Die mitteleuropäischen Fundorte der var.coerulescens stellen weit nach Nordwesten vorgeschobene Ausläufer dort verbreiteter primärer Sippen vonLithospermum arvense L. dar.
Summary In Middle Europe a blue-flowered form ofLithospermum arvense L. sporadically occurs, the distribution of which has been described. Morphological, ecological, phenological and geographical differences are pointed out between this form and the common white-flowered one. This taxon (var.coerulescens DC.) seems to be more primitive than the widely distributed white-flowered weedy form ofLithospermum arvense L. Many forms ofLithospermum arvense L. occur from Southern Russia to the Near East, they are known only unsufficiently. The Middle European localities of var.coerulescens are the extremely Northwestern points of the area of the primary taxa ofLithospermum arvense L.

, , Lithospermum arvense L., , . . (var.coerulescens DC.), , , , . ; var.coerulescens - .
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19.
Summary Approximately 600 different samples of the broad bean collection have been evaluated for crude protein content of the seeds.111 samples were also evaluated for S-aminoacids. The values ranged from 19.5 to 34.0 for protein content and 0.97 to 1.45 for half-cystine and 0.62 to 0.99 for methionine. Protein content was negatively correlated with seed weights, highest values been found in the small seeded samples of Ethiopia and Afghanistan. Mediterranean samples exibited quite large variability. S-aminoacid per protein unit were negatively correlated with the protein content and determination coefficients had intermediate values. Sulphur aminoacids expressed as % of dry seed weight were positively correlated with protein content, but determination values were rather low. Analyses of protein and sulphur aminoacids in seeds from a 10×10 diallel cross scheme gave information on genetic mechanisms involved in the character's control; additive and non additive components of variance were significant, indicating difficulties in practical breeding programmes.
Genetische Variabilität des Gehalts an Rohprotein und schwefelhaltigen Aminosäuren bei Ackerbohnen (Vicia faba L.)
Zusammenfassung Fast 600 Sortimentsnummern der Ackerbohnenkollektion wurden auf den Rohproteingehalt der Samen untersucht, 111 auch auf den auf Gehalt an schwefelhaltigen Aminosäuren. Der Rohproteingehalt schwankt von 19,5 bis 34,0%, der Gehalt an Cystein von 0,97 bis 1,45% und der an Methionin von 0,62 bis 0,99%. Der Rohproteingehalt war negativ mit dem Samengewicht korreliert, die höchsten Werte wurden bei den kleinsamigen Sippen aus Äthiopien und Afghanistan gefunden. Die Sippen aus dem Mittelmeergebiet zeigen eine sehr große Variabilität. Der relative Gehalt an S-haltigen Aminosäuren war negativ mit dem Rohproteingehalt korreliert und das Bestimmtheitsmaß hatte mittlere Werte. Der absolute Gehalt an S-haltigen Aminosäuren war positiv mit dem Rohproteingehalt korreliert, aber das Bestimmtheitsmaß war niedriger.Die Analysen des Rohproteingehaltes sowie des Gehaltes an schwefelhaltigen Aminosäuren der Samen (von F1-Pflanzen) aus einem 10×10 Diallel-Kreuzungsschema ergaben Informationen über genetische Mechanismen in der Kontrolle der Merkmale; die additive und die nicht additive Varianzkomponente waren signifikant und offenbaren die Schwierigkeiten in den praktischen Züchtungsprogrammen.

, , (Vicia faba)
600 . 111 , (-). 19,5 34,0%; — 0,97 1,45%, — 0,62 0,99%. ; . . - , . - , . - f1 ( 10× 10) , ; , .
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20.
Zusammenfassung Das Wachstum von Erbsenkeimlingen wird durch Einwirkung harter Röntgenstrahlen (ab 800 r) gehemmt, ein sofortiger Wachstumsstillstand trat auch bei höheren Dosen nicht ein. Die größte Strahlungsempfindlichkeit besitzt dabei die Wurzelmeristemzone.Bestrahlungsversuche (15–20 kr) ergaben bei mit Bleisalz vorbehandelten und nicht vorbehandelten Erbsensamen starke Schädigungen; gequollenes Saatgut ist empfindlicher als lufttrockenes. Gewächshaus- und Freilandversuche zeigen, daß sich bereits eine Dosis von 4 kr keimungs- und entwicklungshemmend auswirkt, stärkere Dosen hatten auch eine Hemmung des Wurzelwachstums zur Folge. Eine Sensibilisierung durch Bleisalzvorbehandlung des Saatgutes ist unbedeutend oder nicht nachweisbar. Unterschiede in der Wirksamkeit zwischen harter und mittelharter Strahlung sind nicht eindeutig festzustellen.
Summary The growth of pea seedlings is inhibited by the influence of hard X-rays (800 r and more). However a sudden growth stop does not happen even by application of higher doses. The most sensible zone against radiation lies within the root meristem. — Radiation experiments (15–20 kr) yielded serious damages in pea seeds, the effect being the same in by lead salts prepared seeds and in unprepared seeds. Soaked seeds are more sensible than dry ones. Experiments in the green house and in the field prove that already a dose of 4 kr is inhibiting the germination and plant development, higher doses effect also an inhibition of the root development. A sensibilization by preparation with lead salts is hardly or not at all to be proved. Differences in the effectivity between hard and middle hard radiation are not distinctly to be observed.

( 800), . . (15 000–20 000p) ; — . , 4000 ; . , . .
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