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Showing papers by "University of Hohenheim published in 1971"


Journal ArticleDOI
TL;DR: In this article, the cytokinin activity as estimated by the soya callus test was determined in the bleeding sap and in roots of sunflower seedlings grown in nutrient solution for 4-6 weeks with varied nitrogen supply.

64 citations


Journal ArticleDOI
01 Jun 1971-Planta
TL;DR: Cigarette smoke greatly increases the wettability of leaves of Tropaeolum majus, parochetus communis and Chelidonium majus without causing a visible alteration of the submicroscopic structure.
Abstract: The wettability of a leaf surface is defined by the contact angle between a water-droplet and the surface of the leaf. Contact angles of 60–80° were measured on easily wettable leaves. These leaves have no wax on the outer cuticular layer. Contact angles of 130–160° were measured on leaves with a low wettability. These leaves have wax on the outer cuticular layer, which shows submicroscopic structures characteristic of the particular plants. A comparison of the wettability and the different structures of the wax showed no true distinctions. The wax does not adhere strongly to the outer cuticular layer and is cast off in the case of old leaves. Therefore the wetability alters with the age of the leaves. If the wax on young leaves is destroyed or removed by outer influences it can be produced again within a few hours. The rebuilt structure of the wax is not always similar to the original one. When the wax was dissolved by organic solvents no new wax formation was observed. Cigarette smoke greatly increases the wettability of leaves of Tropaeolum majus, parochetus communis and Chelidonium majus without causing a visible alteration of the submicroscopic structure. In this case the leaves recover their water-repellency within a few hours, but not if they were treated with Diesel smoke. When the wax structure was destroyed by fungus or Aleurodina no new wax formation was observed.

46 citations


Journal ArticleDOI
TL;DR: Rib7 mutants of Saccharomyces cerevisiae produce and excrete 6-hydroxy-2,4,5-triaminopyrimidine or a carbohydrate derivative of this compound appears to be an intermediate in the biosynthesis of riboflavin.

45 citations


Journal ArticleDOI
TL;DR: Analysis of the supercoiled DNA of the hemolytic recipient demonstrated that the two large super coiled DNA molecules of E. coli SC52 are transferred during this event, too, suggesting the possible significance of these DNA molecules for hemolysin production and transfer.
Abstract: Covalently closed circular deoxyribonucleic acid (DNA) molecules were isolated by cesium chloride centrifugation in the presence of ethidium bromide from a naturally occurring beta-hemolytic Escherichia coli strain (SC52). The open circular forms have contour lengths of 2.25 +/- 0.1 mum, 24.0 +/- 0.3 mum, and 29.5 +/- 0.5 mum. The beta-hemolytic character of E. coli SC52 can be transferred by conjugation to a nonhemolytic recipient strain. Analysis of the supercoiled DNA of the hemolytic recipient demonstrated that the two large supercoiled DNA molecules of E. coli SC52 are transferred during this event, too. A beta-hemolytic laboratory E. coli strain and several of its derivatives have been shown to contain at least one circular DNA molecule, slightly larger in size than those isolated from E. coli SC52 and its conjugant. The possible significance of these DNA molecules for hemolysin production and transfer is discussed.

44 citations


Journal ArticleDOI
12 May 1971-Nature
TL;DR: Intra and Interspecific Fusion of Protoplasts from Petals of Torenia baillonii and Torenian fournieri is described, paving the way for the development of new probabilistic models of fruit flies.
Abstract: Intra and Interspecific Fusion of Protoplasts from Petals of Torenia baillonii and Torenia fournieri

37 citations


Journal ArticleDOI
TL;DR: A new gymnophallid species is described from the caeca of Tadorna tadorna,Melanitta fusca and Somateria mollissima and from the colon of Melanitta nigra and was recovered from 1 Herring Gull and 4 Eider Duck experimentally infected with the metacercariae.
Abstract: Im Untersuchungsgebiet kommen folgende gymnophallide Larvenstadien vor: eine Metacercarie aus Littorina littorea, zwei Metacercarien in Mytilus edulis und eine Cercarie in Scrobicularia plana. Diese vier waren nicht zu identifizieren und werden hier kurz beschrieben. Bereits bekannte Larvenstadien stammen aus Macoma baltica: Lacunovermis macomae (Lebour, 1908), Parvatrema affinis (Jameson and Nicoll, 1913), Cercaria baltica Markowski, 1936, und Gymnophallus gibberosus Loos-Frank, 1971; und aus Cardium edule: Meiogymnophallus minutus (Cobbold, 1859), Gymnophallus choledochus Odhner, 1900, und Gymnophallus gibberosus. Die junge Metacercarie von M. minutus wird mit der alteren, infektionsreifen verglichen; einige taxonomisch wichtige Merkmale des Adultus werden diskutiert. Eine Tabelle gibt eine Ubersicht uber alle bisher in der Literatur beschriebenen Gymnophalliden mit Synonymen sowie Zwischen- und Endwirtsangaben.

30 citations


Journal ArticleDOI
TL;DR: Li9N2Cl3 was kristallisiert im Anti-CaF2-Typ, wobei die Metallagen entsprechend der Zusammensetzung der Phase unvollstandig with Lithiumionen besetzt sind as discussed by the authors.
Abstract: Durch Umsetzung von Li3N mit LiCl bei hoheren Temperaturen wurden in dem System Li3N/LiCl die Phasen Li11N3Cl2 und Li9N2Cl3 festgestellt. Li9N2Cl3 kristallisiert im Anti-CaF2-Typ, wobei die Nichtmetallagen vollstandig mit Stickstoff- und Chlorionen in statistischer Verteilung, die Metallagen entsprechend der Zusammensetzung der Phase unvollstandig mit Lithiumionen besetzt sind. Die Struktur der Li11N3Cl2-Phase konnte infolge der Kompliziertheit ihres Rontgendiagramms nicht aufgeklart werden.

23 citations



Journal ArticleDOI
TL;DR: Double-labeling experiments indicate that the formation of complex Col E1 DNA occurs by a replication mechanism and not by a random recombination process involving all of the preexisting circular monomer Col E 1 DNA molecules.

20 citations


Journal ArticleDOI
TL;DR: Quantitative determination of phosphoenolpyruvate and erythrose 4-phosphate by the use of a DAHP synthase preparation of Streptomyces aureofaciens is described and the method shows a deviation of ±0.7% from the theoretical values.

18 citations


Journal ArticleDOI
TL;DR: The mechanism of methylation of nucleic acids by Ds-MNNG in vivo in Escherichia coli B is studied in vivo and in vitro in the presence of cysteine to study the mutagenic effect of MNNG.

Journal ArticleDOI
TL;DR: In this article, a method is described for studying the distribution of absorbing roots of fruit trees using the number of light root tips per unit of soil space as a criterion for characterizing the spatial distribution of the absorbing parts of the root systems.
Abstract: A method is described for studying the distribution of absorbing roots of fruit trees using the number of light root tips per unit of soil space as a criterion for characterizing the spatial distribution of the absorbing parts of the root systems. As examples of the use of this method, some results are shown from investigations with apple trees in South-Western Germany. They demonstrate the influence of soil-type and soil management on the distribution of absorbing roots. Striking temporal variations in the number of root tips were observed in the same tree.

Journal ArticleDOI
TL;DR: Some species of Lupinus are considered useful forage in Austral ia, Uni ted Sta tes and Upper E g y p t specially in beef ca t t le-producing areas, and this raises a ques t ion abou t the re la t ion be tween th is estrogenic ac t iv i ty and the congeni ta l skeletal de formi ty
Abstract: Some species of Lupinus are considered useful forage in Austral ia, Uni ted Sta tes and Upper E g y p t specially in beef ca t t le-producing areas. The E g y p t i a n variety--Lupinus termis--proved to be estrogenic [2], a f inding which s t imula ted fu r ther research to ident i fy its phytoestrogen(s) . 500 g of the powdered seeds were Soxhle t -ex t rac ted twice wi th 90% me thano l and the combined filtrates, af ter concentrat ion, were appl ied on paper ch romatograms developed ill t 5 % acetic acid. Unde r U.V. light, the dr ied chromatograms showed a dark brown spot ( R f = 0 . 3 4 ) which was e h t e d in cold me thano l and subjec ted to hydrolysis and f rac t ionat ion after which purif icat ion was achieved chromatograph ica l ly [10]. The Rf value toge the r wi th the maxim u m absorp t ion (263 m[z) sugges ted t h a t our isolated comp o u n d was similar to b iochanin A (4\"-methyI e ther of gentstein), f i rs t de tec ted in red clover by Pope et al. [8]. Fu r t he r conf i rmat ion of its s t ruc ture was accompl ished by the ba thochromic shif t [5]. The peak was shif ted to 273 mbt af ter sa tu ra t ing the e thanol-e lut ion of t he de tec ted spot wi th anhydrous sodium ace ta te or af ter addi t ion of a luminium chloride to a concent ra t ion of 0.1%. Fu r the r conf i rmat ion was necessary because H 6 r h a m m e r et al. [6] have isolated gents tein f rom another species of lupin, and because free hyd roxy l groups are p resen t in posi t ions C-5 and C-7 of bo th phy to estrogens. Thinlayer ch roma tog raphy Was appl ied by spott ing the isolated subs tance agains t the reference estrogenic isoflavones (genistein, b iochanin A, fo rmonone t in and daidzein) on silica gel plates developed in 2 solutions: benzol /np ropanol (89/11) and benzol /e thyl ace ta t e /me thano l /pe t ro leum e ther (6/4/t/2). The Rf value af ter spraying the chromatograms wi th d iazo ta ted sulfanilic acid excluded the presence of genistein. Quant i t a t ive es t imat ion of b iochanin A, pe r fo rmed chromatographical ly [10], gave an ave rage value of 225 m g per kg of d ry seeds. I ts estrogenic ac t iv i ty was tes ted biologically in groups of 10 immatu re female mice [3] and the da t a of the i r f reshly dissected uteri were analysed s ta t is t ical ly using the \" t \" t e s t (table). In t e rms of estradiol equivalents , the relat ive po tency of the isolated compound is 1:400000, calculated according to F inney et al. [4]. This raises a ques t ion abou t the re la t ion be tween th is estrogenic ac t iv i ty and the congeni ta l skeletal de formi ty in calves (crooked calf syndrome) which is associated wi th t he ma te rna l consumpt ion of lupin [12]. Schupe et al. [ t l ] a t t r ibu ted this effect to the toxic i ty of Lupinus which is main ly due to its alkaloid cont en t [t]. ]But as lupin alkaloids have p roved to be estrogenic [2] and as b iochanin A is t r ans fo rmed to more po t en t estro-

Journal ArticleDOI
TL;DR: DAHP synthase activity of Streptomyces aureofaciens is not repressed in cells grown in minimal medium supplemented with phenylalanine, tyrosine or tryptophan, and metabolites of the aromatic pathway are tested as potential inhibitors of DAHP synth enzyme activity.

Journal ArticleDOI
TL;DR: The influence of growth temperature and of stage of maturity on lipid synthesis in seeds, oat plants were fed with 14 CO 2 at different stages after flowering, and the 14 C-incorporation into the grain lipids was determined at 2, 24, and 48 hours after the end of 14CO 2 -application to show a direct influence of temperature on fatty acid biosynthesis in oat grains.
Abstract: To elucidate the influence of growth temperature and of stage of maturity on lipid synthesis in seeds, oat plants (Avena sativa nuda L., variety NOS) were fed with (14)CO(2) at different stages after flowering, and the (14)C-incorporation into the grain lipids was determined at 2, 24, and 48 hours after the end of (14)CO(2)-application. By changing growth temperature from 12 C to 28 C after the application of (14)CO(2) to intact plants, a higher (14)C-labeling of saturated fatty acids was found at the higher temperature. At 28 C, palmitic and stearic acids contained 23% and 9% respectively of total fatty acid-(14)C shortly after the (14)CO(2)-application, whereas at 12 C the corresponding values were 19% and 4%, respectively. Within 2 days (14)C-activity of saturated fatty acids decreased at both temperatures, but to a lesser degree at 28 C. The higher (14)C-labeling of saturated fatty acids and its lower decrease within 2 days at 28 C clearly show a direct influence of temperature on fatty acid biosynthesis in oat grains.At all stages of grain growth, oleic acid had the highest (14)C-activity of all fatty acids shortly after the (14)CO(2)-application. However, (14)C activity of oleic acid rapidly decreases in favor of linoleic acid. With increasing maturity, the intensity of lipid synthesis in the grains decreases; simultaneously, the relative amount of (14)C-saturated fatty acids increases primarily at the expense of (14)C-oleic acid. These tendencies, which were observed in oat plants grown at day temperatures of 12 C during seed development, seem to be paralleled by lipid synthesis in younger grains grown at day temperatures of 28 C. This indicates an indirect influence of growth temperature on lipid synthesis in oat grains during maturation.


Journal ArticleDOI
TL;DR: The data obtained from the analysis of the four Petunia hybrida mutants point to an important role of the vegetative nucleus in the development of the pollen tube, in disagreement with results of DNA-measurements described for a limited number of other species.
Abstract: The DNA-content of generative and vegetative nuclei in mature pollen grains of four Petunia hybrida mutants was determined by cytophotometry. In addition the DNA-content of generative and vegetative nuclei in the pollen tube of two of these four mutants (virescens-2 n and ustulata-2 n) was cytophotometrically measured.The DNA-values found in the generative nuclei indicate that the DNA-replication continues in the mature pollen grain and comes to an end only after the migration of the nuclei into the pollen tube. These data are in disagreement with the results of DNA-measurements described for a limited number of other species which all show completion of DNA-synthesis during the maturation stage of the pollen grains.The vegetative nuclei of the four Petunia mutants studied show significant differences in the onset of the degenerative phase. Extreme variation is manifested in the ustulata-2 n mutant in which the degeneration of nuclei may reach the final stage in the maturing pollen grain. However in this mutant vegetative nuclei with an unaltered DNA-content may also be demonstrated in the pollen tube. Some of the vegetative nuclei in the pollen tube of ustulata-2 n exhibit an increased amount of DNA which could be the result of differential DNA-replication in the vegetative nuclei. The decrease of the DNA-content in a certain fraction of the vegetative nuclei in the maturing pollen grain does not agree with observations made in other species by several authors who report DNA constancy until the pollen grain is fully mature.The data obtained from the analysis of the four Petunia hybrida mutants point to an important role of the vegetative nucleus in the development of the pollen tube. The Petunia hybrida mutants may be regarded as especially favourable material for investigations concerning the function of the vegetative cell in the development of the pollen grain and pollen tube.

DOI
01 Jun 1971
TL;DR: In this paper, the identifizierten Bauchmarkneurone mitperipherwarsverlaufenden Axonen (PN) wurden in 4 Gruppen unterteilt:
Abstract: Die Nervenzellen and -bahnen der Bauchmarkganglien von Lumbricus terrestris wurden in osmiumfixierten Serienquersehnitten moglichst vollstandig identifiziert and eingehend besehrieben. Folgende Gruppen lassen sich trennen: In jeder Bauchmarkseite wurden 5 Bundel von sensorischen, anscheinend aus den Epidermissinnesorganen stammenden Fasern lokalisiert (SLB). Sie sind mit den von Coggeshall (1965) elektronenoptiseh dargestellten and als Neuropil bezeiehneten Faserchen von nur 0,I bis 0,3 μm Durchmesser identisch. Die Zellsomata der ventralen Riesenfasern (VRF) wurden aufgefunden. Diese Fasern bestehen ebenso wie die dorsalen RF aus unizellularen, rich uber eine lange Strecke uberlappenden, segmentalen Abschnitten. Sie stehen in enger morphologischer Beziehung zu einem der sensorischen Langsbundel. Die identifizierten Bauchmarkneurone mitperipherwartsverlaufenden Axonen (PN) wurden in 4 Gruppen unterteilt: Die PN1 Bind hoterolaterale, monopolare Neurone mit Kollateralen im dorsalen Neuropil; ihre Axone verlassen das Bauchmark durch alle 3 Seitennerven-Paare. PN2, PN3 and PN4 sind homolaterale Neurone mit Kollateralen im ventralen Neuropil. PN2 and PN4 sind monopolar ; ihre Axone treten durch die SN3 des gleichen bzw. des vorangehenden Segments aus dem Bauchmark. Die PN3 sind bipolar, gelegentlich tripolar ; ihre Axone verlassen das Bauchmark durch 2 (bzw. 3) SN, eines stets durch den SN3 des gleichen Segments, das (oder die beiden) andere(n) durch den SN1 des gleichen oder (und) des nachfolgenden Segments. Lage, Anzahl und Cytologie der in Gruppen vorkommenden PN-Somata werden eingehend geschildert. Die Interneurone des Bauchmarks (IN; RF nicht einbegriffen) werden drei Hauptgruppen zugeordnet : Der grosere Teil der IN (uber die Halfte aller Bauchmarkneurone) besteht aus kleinen Neuronen mit kurzen, sich our in das homolaterale Neuropil erstreckenden Fasern (KIN). Die zweite Gruppe wird von groseren Interneuronen gebildet (GSIN), die anscheinend streng metamer und symmetrisch in beiden Ganglionhalften vorkommen. Sie machen je nach Korperregion $${\raise0.7ex\hbox{$1$} \!\mathord{\left/{\vphantom {1 7}}\right.\kern- ulldelimiterspace}\!\lower0.7ex\hbox{$7$}}---{\raise0.7ex\hbox{$1$} \!\mathord{\left/{\vphantom {1 3}}\right.\kern- ulldelimiterspace}\!\lower0.7ex\hbox{$3$}}$$ aller Neurone des Ganglions aus. Ihre homo- oder heterolateralen Axone konnen in Langsrichtung intra- oder intersegmental oft uber eine Segmentlange hin verfolgt werden. Die dritte Gruppe wird von polysegmentalen IN (PSIN) gebildet, mit sehr grosen Zellkorpern, die weder metamer noch bilateral-symmetrisch angeordnet sind. Die Axone erstrecken sich polysegmental uber mindestens 30 Segmente und bilden auffallige Hauptfaserzuge (HFZ) in der Peripherie der Faserregion des Bauchmarks. Zuletzt wird die Anzahl und Verteilung der Neurone in Ganglien verschiedener Bauchmarkregionen angegeben und mit der Anzahl der Nervenfasern in den Konnektiven verglichen. Die Anzahl der kleinen Interneurone (KIN) ist je nach Bauchmarkregion sehr unterschiedlich, wahrend die ubrigen Neurone regelmasig auftreten. In der Diskussion wird einerseits die morphologische und cytologische Konstanz vieler Einzelelemente im Regenwurmbauchmark hervorgehoben und auf die funktionellen Konsequenzen hingewiesen. Auserdem wird versucht, durch Vergleich mit Angaben uber andere Tierarten und Gegenuberstellung morphologischer und funktioneller Befunde allgemeine Prinzipien fur den Zusammenhang zwischen Struktur und Funktion im Bauchmarkaufbau herauszustellen.



Journal ArticleDOI
TL;DR: Comparative studies of the chromosome cytology of the fleas of the Marsupialia do not support the concept of a closer phylogenetic relationship between the Aphaniptera and Nematocera, but do not preclude the possibility of a kinship of AphanIPtera and Neomecoptera.
Abstract: 1. Die phylogenetischen Verwandtschaftsbeziehungen der Flohe (Aphaniptera = Siphonaptera) zu den anderen Ordnungen der Insekten sind ungeklart. Vergleichende cytogenetische Untersuchungen bei den Flohen werden unternommen, um diese Frage aufklaren zu helfen. 2. Eine Hamburger und eine Londoner Population des Pestflohes Xenopsylla cheopis Rothschild, 1903, haben einen Chromosomenbestand von 2n = 14 A + X1X2Y (Mannchen) und 14A + X1X1X2X2(Weibchen). Das X1X2Y-Geschlechtstrivalent ist auf die mannliche Meiose beschrankt, in der Oogenese treten 2 Geschlechtsbivalente (X1X1 und X2X2) auf. 3. Eine Plochinger Population des Hausmausflohes Leptopsylla segnis Schonherr, 1811, zeigt 2n = 18 A + XY (Mannchen): 18 A + XX (Weibchen) Chromosomen. 4. Die cytogenetischen Befunde sprechen gegen eine nahere phylogenetische Beziehung zwischen Aphaniptera und Nematocera. Sie widersprechen nicht den neueren Vorstellungen von einer naheren phylogenetischen Verwandtschaft zwischen den Aphaniptera und Neomecoptera. 5. Weitere Untersuchungen der Chromosomen der Aphaniptera und Neomecoptera sind jedoch notwendig, bevor bestandigere Aussagen gemacht werden konnen. Die Analyse der Chromosomencytologie der Flohe der Marsupialia, welche als die ursprunglichsten von allen lebenden Formen angesehen werden, konnte besonders aufschlusreich sein.

Journal ArticleDOI
TL;DR: Accumulation tests reveal, that mutant HK 793 does not represent a separate gene “rib6” but is defective in rib5, and is therefore classified as a mutant of rib5.
Abstract: Accumulation tests reveal, that mutant HK 793 does not represent a separate gene “rib 6” but is defective in rib 5.

Journal ArticleDOI
TL;DR: Studies of the absorption and translocation of 14C-2,4-D in Chenopodium album L., Galinsoga parviflora Cav.
Abstract: Summary Studies of the absorption and translocation of 14C-2,4-D in Chenopodium album L., Galinsoga parviflora Cav., Datura stramonium L. and Galium aparine L. in relation to their susceptibility gave the following results: In G aparine (resistant) there was little transport of 2,4-D applied to the leaves, and a probable relationship between resistance and the immediate binding of the 2,4-D in the treated leaf. D. stramonium (relatively resistant) transported 2,4-D in considerable amounts alter uptake through the leaf, while C. album (very susceptible) and G. parviflora (susceptible) were intermediate in respect of 2,4-D translocation. No relationship between susceptibility of these four species and 2,4-D uptake and translocation from the leaves could be established. After application to the root systems of the four species, 2,4-D was taken up and translocated in the shoot to varying extents. In G. aparine much 2,4-D was taken up and translocated. In contrast to leaf application, the herbicide was not immediately converted into a strongly-held immobile form. In C. album, G. parviflora and D. stramonium, however, no 2,4-D was translocated in the shoot. There was thus no correlation between susceptibility and shoot transport of 2,4-D in the four species studied. Distribution du 2,4-D marque au 14C dans des especes de mauvaises herbes presentant des sensibilites diverses

Journal ArticleDOI
TL;DR: In this paper, a Pulverdiagramme zeigten das Vorliegen eines Gemisches yon TI2X and La2X 8 vom TIX, Lanthan and Chalkogen wurden zwischen 400 and 1 000 erhitzen.
Abstract: Bet Versuchen zur Darstellung tern~irer Chalkogenide des Thalliums mit Lanthan des Typs TILaX 2 (X= S, Se, Te) durch Umsetzung st6chiometrischer Gemische yon TIX, Lanthan und Chalkogen wurden zwischen 400 und 1 000 ~ zwar dem Aussehen nach homogene Reaktionsprodukte erhalten, ihre Pulverdiagramme zeigten jedoeh das Vorliegen eines Gemisches yon TI2X und La2X 8 vom Th~P4-Ty p. Beim Erhitzen der Reaktionsprodukte auf 1 100 ~ folgte eine Entmischung in TI2X ulld in die im ThsPt-Ty p kristallisierenden Lanthanehalkogenide. Diese enthielten einen erheblichen Anteil Thallium. I~ine Untersuchung der einzelnen Systeme ergab, daf3 die Lanthansesquichalkogenide TI2X bis zur Zusammensetzung TILasX s aufnehmen k6nnen, wobei das Gitter vom ThsP4-Typ nicht nur erhalten, sondern auch stabilisiert wird. Die durch Entmischung der Umsetzungsprodukte erhaltenen und die durch Synthese hergestellten Verbindungen erwiesen sich nach Analyse, Gitterkonstanten und pyknometriseher Diehte als identisch. Durch den Einbau des gr6Beren Thalliums in die Leerstellen des La2X2-Gitters tritt in den drei Systemen (vgl. Tabelle) eine geringfflgige Gi t terwei tung ein.

Journal ArticleDOI
TL;DR: In cultured human liver cells (Chang) ethidium bromide prevents the de nova formation of supercoiled mitochondrial DNA, (2) existing supercoiling mitochondrial DNA is degraded, and (3) normal synthesis of super coiled mitochondrialDNA is restored after removal of the drug.

Journal ArticleDOI
TL;DR: St studies of the uptake and translocation of 14C-labelled 2, 4-D, MCPA and aminotriazole in Agrostemma githago L. and Tussilago farfara clarified the behaviour of the herbicides in both species.
Abstract: Summary Studies of the uptake and translocation of 14C-labelled 2, 4-D, MCPA and aminotriazole in Agrostemma githago L. and Tussilago farfara L. clarified the behaviour of the herbicides in both species. In A. githago, MCPA was more freely mobile than 2,4-D after application to the leaf; it was distributed in the plant more rapidly and in greater quantity. Similarly, following root uptake MCPA was transported in the shoot in greater amounts than was 2,4-D. There is a clear relationship between the susceptibility of A. githago to MCPA and the mobility of the herbicide in the plant. In T. farfara, 2,4-D and aminotriazole applied to the leaves were equally well absorbed and relatively rapidly translocated. During the period up to 72 h the amounts of herbicide in the plant increased to similar levels; after that, 14C activity in plants treated with 2,4-D fell slightly whereas there was further accumulation of aminotriazole. Following uptake through the roots, translocation and accumulation in the leaves were considerably greater with aminotriazole than with 2,4-D. The lack of accumulation of 2,4-D could be a factor in the resistance of T. farfara to this herbicidie. Recherches sur l'absorption et la migration d'herbicides marques au14C dans Agrostemma githago L. et Tussilago farfara L.

Journal ArticleDOI
TL;DR: In this paper, the chemische Zusammensetzung der Fruchtschale von 8 verschiedenen Jonathan-Varietaten was investigated, i.e., the Wasserverlust von Fruchtten und deren Perforations-widerstand untersucht.
Abstract: Es wurde die chemische Zusammensetzung der Fruchtschale von 8 verschiedenen Jonathan-Varietaten Bowie der Wasserverlust von Fruchten und deren Perforations-widerstand untersucht. Es hat sich ergeben: 1. Die vom Wachs befreiten Apfelsehalen enthalten anteilmaBig zwischen 70 and 800,10 Cutin, um 15% tanninartige Substanzen and ca. 30,10 Cellulose. Von den Cutinsauren wurden 3-Hydroxypalmitinsaure, 10,16-Hydroxypalmitinsaure und 9,10,18-Hydroxystearinsaure identifiziert. 2. Der Rohfettgehalt der Oberflachenwachse liegt bei den meisten untersuchten Varietaten um 1,3 mg/cm2 Schalenoberflache. Von den freigemachten hoheren Fettsauren dominiert Linolsaure; anteilmasig folgen Ol- and Palmitinsaure. 3. Der Paraffingehalt der Oberflachenwachse varuert zwischen 16 und 23%. Verbindungen mit ungerader C-Zahl herrschen vor. Hauptkomponenten sind Nonacosan (70–75% Anteil) und Heptacosan (ca. 20%). 4. Nach Entfernen der Schalenwachse mittels Athanol steigen die pro Zeiteinheit ermittelten Wasserverluste um das 2–3fache gegenuber den Kontrollfruchten. 5. Die Schalen- und Fleischfestigkeit ist auf den sonnenexponierten Fruchtseiten hoher als auf den Schattenseiten. 6. Die Fruchte der Sorte Idared zeichnen sich gegenuber denen der ubrigen Varietaten durch die geringsten Wasserverluste aus. Ihre Schalen haben den hochsten Cutinanteil, von den Fettsauren des Oberflachenwachses erreicht die Palmitinsaure den hochsten Wert, wahrend ihr Paraffingehalt dem der anderen Sorten entspricht. 7. Obwohl die chemische Zusammensetzung der Apfelsehalen einen masgeblichen Einflus auf die Wasserabgabe reifer Fruchte hat, sind in diesem Zusammenhang auch die Oberflachenstrukturen und anatomisch-histologische Fakten von Bedeutung.

Journal ArticleDOI
TL;DR: C r a n i a d W a n d e r t m a n exper imente l l die B i ldung eines ,, H i r n w u r m s " , keh ren die P a r a s i t en n ich t in den Gas te r zuriick, d i rekt u n d tiber die physio logische Akt iv i t~ t des Wir tes.
Abstract: C r a n i a d W a n d e r u n g . Veran twor t l i ch for die C a u d a d W a n d e r u n g ist der ,Hirnwurm\" (evtl. i m Z u s a m m e n w i r k e n mi t d e n USG) ; v e r h i n d e r t m a n exper imente l l die B i ldung eines , , H i r n w u r m s \" , keh ren die P a r a s i t en n ich t in den Gas te r zuriick. 3. Die T e m p e r a t u r wi rk t sich, d i rekt u n d tiber die phys io logische Akt iv i t~ t des Wir tes , au f die E n t w ick lungs dauer (a) u n d die E n d v e r t e i l u n g (b) der P a r a s i t e n aus. a) I m u n t e r s u c h t e n T e m p e r a t u r b e r e i c h verki i rzen s te igende T e m p e r a t u r e n den Z e i t r a u m I n v a s i o n s b e g i n n E n z y s t i e r u n g von 54 T a g e n bet 10 ~ auf 2,5 Tage bet 26 ~ b) Bet k o n s t a n t e n T e m p e r a t u r e n im Bereich 16 -26 ~ wird die charak te r i s t i sche lEndverte i lung der MC nu r in e twa 50~o der Versuchst iere erreieht , bet den. flbrigen Ame i sen en twicke ln sieh einige Zys t en in T h o r a x und Kopf. Vari ier t m a n die T e m p e r a t u r dagegen in 24 h R h y t h m e n zwischen 16 u n d 26 ~ ergeben sich Ver te i lungen, die den na t f l r l ichen VerhKltnisser~ (92% cha rak te r i s t i sche Ver te i lungen, 8% Abweichungen) en t sp rechen . JEs ist zu v e r m u t e n , daft die T e m p e r a t u r eine Ze i tgebe r funk t ion erf[illt und die Re i fung der P a r a s i t e n synehron i s i e rend beeinfluBt. W e n n m a n ether befal lenen Ameise s~mt l iche MC e n t n i m m t und, itl kleine G r u p p e n aufgetei l t , m e h r e r e n ge sunden Ameisen implan t i e r t , so is t bis z u m Beg inn der C a u d a d W a n d e r u n g jede Oruppe bef~higt , die charak te r i s t i sche Ver te i lung n i t e igenem , , H i r n w u r m \" auszub i lden ein bemerkenswer t e s Regu la t i onsve rm6gen , das eine hohe p rospek t ive Po tenz der unre i fen MC e rkennen l~iBt. Auch di rekt aus e inem Sehle imbal len e n t n o m m e n e Pa ra s i t en lassen sieh in den Gas te r gesunde r Ameisen t r ansp lan t i e ren . Obwohl sie weder den Kropf d u r c h w a n d e r t noch e inen W u n d verschluf3 ausgebi lde t haben , s ind sie in der Lage, sich zu e inem , , t t i rnwlirm\" oder zu invasionsf{ihigen MC zu en t wickelli. Dieser Be fund gibt Zeugliis ffir eine brei te Pr~tadaprat ion, die f[lr evtl . no twendige Ki ide rungen im lEntwicklungsgang bere i t s teh t .

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TL;DR: In this paper, the authors described the isolation of a mutant 62-l AC of Aerobacter aerogenes producing compound A, a labile intermediate of the 4aminobenzoic acid biosynthesis.