04 Fakultät Energie-, Verfahrens- und Biotechnik
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Item Open Access Incorporation of 14C-photosynthate into major chemical fractions of leaves and bark of Ceratonia siliqua L. at different seasons(1993) Diehl, Susanne; Kull, Ulrich; Diamantoglou, StergosParts of branches of Ceratonia siliqua (L.) were exposed to 14CO2 for 3h during the growth period in April, after termination of growth (end of May), in the summer drought period (August) and in the cool winter (February). Twigs were harvested immediately after the end of the feeding period as well as after 48 and 144h. Simultaneously with the last harvest of exposed plant parts, controls from outside the exposure-chamber were also gathered. The total 14C-incorporation into leaves and bark as well as the labelling and contents of soluble sugars, starch, total lipids and other precipitable soluble compounds were determined. Total 14C-incorporation immediately after termination of 14CO2 application is a measure of the assimilation rate; it was high and nearly identical in April and May, but low (only about 5% of the April value) in summer ;and winter. The incorporation of 14C into soluble structural components was highest in April. Uptake of total 14C and labelling of soluble compounds during the 6-day period of the experiments show that metabolic rates were very low in summer but high during spring. The turnover of soluble compounds in February was remarkably high regarding the low CO2-fixation rate. The labelling of soluble sugars in leaves decreased in all experiments; the specific activity of starch remained rather stable. The incorporation of 14C into the lipid fraction was weak in all seasons and significant alterations took place only during the growing period. Variation in assimilation rates of Ceratonia at different seasons was comparable to that found for other mediterranean species using IRGA methods. There was no indication that lipids in Ceratonia are true storage compounds and participate in cyclic metabolic processes preventing stress effects. The weak turnover of lipids leads to the conclusion that maintenance costs for these compounds, as calculated by Merino et al. (1984). perhaps are too high, at least for Ceratonia. Our results do not suggest a specific adaptation of the metabolism of storage compounds to summer drought in Ceratonia.Item Open Access Die Fettsäurenzusammensetzung der verseifbaren Lipide aus Nadeln von Taxus baccata L. an Standorten unterschiedlicher Immissionsbelastung(1979) Höllwarth, Michael; Kull, UlrichThe fatty acid composition of saponifiable lipids in needles of Taxus baccata grown in three areas with different immission-stresses (forest, park within the town, place of high traffic-density in the city), was measured by gas-liquid-chromatography of methyl esters during the course of a year. No distinct periodicity of fatty acids during the year was found, but there were characteristic differences of the fatty acid patterns from the different places, with regard mostly to palmitic, linoleic, and linolenic acids. At places with higher immission-stresses the percentage of saturated fatty acids is reduced and that of linoleic and linolenic acids increased. Similar effects were induced when twigs of Taxus were fumigated with 0.5 ppm SO 2. Distinct effects were also measured after fumigation with car-exhaust-gas.Item Open Access Kohlenhydratgehalte und osmotische Verhältnisse bei Blättern und Rinden von Arbutus unedo L. und Arbutus andrachne L. im Jahresgang(1984) Diamantoglou, Stergos; Kull, UlrichIn den letzten Jahren wurden an den beiden Arbutus-Arten des Mittelmeergebiets mehrfach ökophysiologische Untersuchungen durchgeführt, insbesondere nachdem sich gezeigt hatte, daß sie sich beim mittäglichen Spaltenschluß unterschiedlich verhalten. Befunde zur Speicherungsphysiologie liegen von verschiedenen Ericaceen Mitteleuropas vor; daher schien es von Interesse, die mediterrane Gattung Arbutus damit zu vergleichen. Über den Lipidhaushalt der beiden Arbutus-Arten wurde bereits berichtet; dabei zeigte sich, daß im Gegensatz zu verschiedenen mitteleuropäischen Ericaccen und zu anderen mediterranen Sklerophyllen in Arbutus keine sehr starke Lipidakkumulation stattfindet. Wie bei anderen Sklerophyllen liegt das Minimum des Lipidgehaltes in der Zeit der sommerlichen Dürre. Wir berichten hier über die Jahresperiodik der Kohlenhydrate und des Energiehaushaltes der Reservestoffe in Blättern und Rinden der beiden Arbutus-Arten.Item Open Access Das jahresperiodische Verhalten der Fettsäuren in Rinden und Blättern von Pinus halepensis Mill. und Schinus molle L.(1981) Diamantoglou, Stergos; Kull, UlrichThe fatty acid composition of the saponifiable lipids from barks and leaves of Pinus halepensis and of Schinus molle was investigated throughout the period of a year by gas liquid chromatography. Both species showed a great variety of different fatty acids of saponifiable lipids. In barks of Pinus, the contents of stearic, oleic and linoleic acids are higher during late winter and the growth period, whereas the percentage of behenic, lignocerinic, octadecatetraenoic, eicosatrienoic, and eicosatetraenoic acids was larger during the summer drought period and the autumn months. In the needles of Pinus, the contents of linolenic acid and of the short-chain acids (caprinic and laurinic) showed maxima during the winter and the growth period. In barks of Schinus we found a larger fraction of linolenic, erucic, and lignocerinic acids during the same period; in the leaves of this species linoleic, linolenic, behenic, and lignocerinic acids accumulated during the winter. There is no unequivocal influence of summer-drought on fatty acid pattern. In all species of linoleic and linolenic acids the highest percentage is shown during the humid winter and growth periods, which seems to reflect the metabolic activity of the investigated tissues.Item Open Access Jahreszeitliche Dynamik der Fettspeicherung von Loiseleuria procumbens und anderen Ericaceen der alpinen Zwergstrauchheide(1982) Tschager, Angelika; Hilscher, Helga; Franz, S.; Kull, Ulrich; Larcher, WalterDas Ausmass der Fettspeicherung und die Zusammensetzung der Fette in Blättern, oberirdischen Sprossachsen, unterirdischen Pflanzenteilen und reproduktiven Organen von Loiseleuria procumbens aus der alpinen Zwergstrauchheide in 2000 m MH wurde zu phänologisch bezeichnenden Terminen histochemisch und nach Extraktion gravimetrisch sowie dünnschicht- und gaschromatographisch bestimmt. An Arcloslaphylos uva-ursi, Vaccinium gaultherioides, V. myrlillus, V. vitis idaea, Calluna vuigaris und Empetrum hermaphroditum erfolgten gravimetrische Bestimmungen des Fettgehalts jeweils im Sommer und im Winter, histochemische Untersuchungen zu verschiedenen Jahreszeiten. Die physiologische und ökologische Bedeutung der erheblichen Akkumulation von Fetten durch Loiseleuria und andere Ericaceen der alpinen Zwergstrauchheide ist noch nicht klar. Zwar konnte gezeigt werden, dass Fett während intensiver Wachstumsphasen und auch nach Dunkelstellen im Winter mobilisiert wird, doch weist der hohe Fettgehalt vergilbender Blätter darauf hin, dass Fett möglicherweise auch das Ergebnis einer Verschiebung im Gesamtstoffwechsel der auf kältebelastete und stickstoffarme Standorte spezialisierten Pflanzen sein könnte.Item Open Access Manometrische Atmungsmessungen an Protoplasten von Petunia(1975) Hoffmann, Franz; Kull, Ulrich; Potrykus, IngoIsolierte Protoplasten höherer Pflanzen scheinen so manchen experimentellen Vorteil für die Beantwortung unterschiedlichster Fragestellungen der Botanik zu bieten. Während sich die überragende Mehrzahl der vorliegenden als auch ein immer noch hoher Prozentsatz der neu erscheinenden Protoplasten-Publikationen mit Problemen der Isolierung und Feinstruktur beschäftigt, liegen über das Verhalten der Protoplasten an sich nur wenige Arbeiten vor. Über die Atmung von Protoplasten fanden wir keine Angaben. Zur Charakterisierung der Protoplasten von Petunia haben wir daher die Atmungsraten untersucht.Item Open Access Item Open Access Einfluß von Zeatin auf Atmung und Photosynthese der Mesophyll-Protoplasten von Petunia(1975) Kull, Ulrich; Hoffmann, FranzApplication of 1 ppm zeatin raises the respiration rate (measured by the Warburg method) of leaf mesophyll protoplasts of Petunia hybrida by about 50% after 4 h; afterwards there is a rapid decrease. While the rate of respiration in the controls rises after 5 to 6 h, 1 ppm zeatin has a strong inhibitory effect. When the protoplasts are incubated with 0.1 ppm zeatin, the rise in the rate is much slower, and after 7 h the rate is 30 % higher than in the controls. Abscisic acid (10 ppm) decreases the respiration rate so that after 5h it is less than half that of the controls. Later on there is a rise in the controls, perhaps caused by senescence promoting effects of abscisic acid. The photosynthetic rate of the mesophyll protoplasts measured by 14CO2 fixation decreases with increasing age of the preparation. The protoplasts previously incubated with zeatin for 1 to 3 h show an increase in photosynthesis: with 0.1 ppm zeatin the 14C-fixation rate is higher the longer the hormone could operate. With 1 ppm zeatin we get a typical optimum curve similar to that for respiration. These optimum curves indicate the inhibitory effect of high concentrations of zeatin on respiration and photosynthesis.Item Open Access Seasonal trends in energy content and storage substances in the mediterranean shrub Ephedra(1989) Diamantoglou, Stergos; Rhizopoulou, Sophia; Herbig, Astrid; Kull, UlrichGreen branches of a shrub of Ephedra distachya L., growing in Athens, Greece, were investigated. The crude fibre content rises during the late growth period, levels off during winter, then declines as new shoots emerge in spring. The content of soluble sugars and of starch is high during winter, but rather low during the dry season. The content of total lipids rises during winter, especially during the late growth period until June and declines during the drought period. During the winter months in the total saponifiable lipids the percentage of linoleic and linolenic acids is high; however, during the growth and the drought period the content of palmitic acid is rather high. The contents of total nitrogen and protein nitrogen decrease in late spring and remain low until the end of the summer drought. Thereafter, both values rise markedly. Stored energy is lowest at the end of the summer drought period. The ashfree calorific values vary little throughout the year (but the difference is significant) : the highest value is obtained in November (19782 J/g), the lowest in May (19298 J/g). From our data, the tissue.construction cost was estimated to be 1.41-1.47 g glucose/g dry weigth. Ephedra distachya is suited to the mediterranean climate, as seen by its ability to adjust to climatic changes during the year while undergoing periods of growth and quiescence. The accumulation of sugar during the winter months suggests that Ephedra is also capable of growing under cold-stress conditions.Item Open Access The flora, vegetation and monuments of classical Greece(1987) Kull, Ulrich; Diamantoglou, StergosAttica, Central Greece ("Roumeli") and the Peloponnese ("Morea") form the heart of classical Greece. In this area, the landscape, vegetation and human history are intimately associated and interwoven. All three will be given equal consideration during this excursion, where the visit of the sites of Greek Antiquity will each time provide insights into the flora of the past and present. Among and around the ruins, the different types of the characteristic sclerophyllous vegetation of the Mediterranean, including the products of its degradation by man, may be studied. The altitudinal zonation of the vegetation will also be demonstrated, e.g. on Mt. Parnassus and in the central Peloponnese where relatively undisturbed Abies forests still cover extensive areas.