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1	Phänologie - die Jahreszeiten der Pflanzen 10 August 2021 (has links) Die Phänologie beschäftigt sich mit der Entwicklung von Pflanzen im Jahresverlauf. Das Wort Phänologie stammt aus dem Griechischen und bedeutet wörtlich: Die Lehre von den Erscheinungen. Und genau darum geht es: Phänologen beobachten die regelmäßig wiederkehrenden Wachstums- und Entwicklungserscheinungen von Pflanzen. Dazu gehören z. B. Blühbeginn, Fruchtreife und Laubfall. Die Veränderungen notieren Phänologen in einem speziellen Kalender, der zehn Jahreszeiten aufweist. Dieser phänologische Kalender orientiert sich an den charakteristischen Entwicklungsstadien typischer Zeigerpflanzen ( z. B. Schneeglöckchen, Holunder, Salweide). Redaktionsschluss: 30.10.2019 info:eu-repo/classification/ddc/570 ddc:570 Sachsen; Phänologie
2	Divergent functions of the Arabidopsis mitochondrial SCO proteins: HCC1 is essential for COX activity while HCC2 is involved in the UV-B stress response Steinebrunner, Iris, Gey, Uta, Andres, Manuela, Garcia, Lucila, Gonzalez, Daniel H. 11 July 2014 (has links) (PDF) The two related putative cytochrome c oxidase (COX) assembly factors HCC1 and HCC2 from Arabidopsis thaliana are Homologs of the yeast Copper Chaperones Sco1p and Sco2p. The hcc1 null mutation was previously shown to be embryo lethal while the disruption of the HCC2 gene function had no obvious effect on plant development, but increased the expression of stress-responsive genes. Both HCC1 and HCC2 contain a thioredoxin domain, but only HCC1 carries a Cu-binding motif also found in Sco1p and Sco2p. In order to investigate the physiological implications suggested by this difference, various hcc1 and hcc2 mutants were generated and analyzed. The lethality of the hcc1 knockout mutation was rescued by complementation with the HCC1 gene under the control of the embryo-specific promoter ABSCISIC ACID INSENSITIVE 3. However, the complemented seedlings did not grow into mature plants, underscoring the general importance of HCC1 for plant growth. The HCC2 homolog was shown to localize to mitochondria like HCC1, yet the function of HCC2 is evidently different, because two hcc2 knockout lines developed normally and exhibited only mild growth suppression compared with the wild type (WT). However, hcc2 knockouts were more sensitive to UV-B treatment than the WT. Complementation of the hcc2 knockout with HCC2 rescued the UV-B-sensitive phenotype. In agreement with this, exposure of wild-type plants to UV-B led to an increase of HCC2 transcripts. In order to corroborate a function of HCC1 and HCC2 in COX biogenesis, COX activity of hcc1 and hcc2 mutants was compared. While the loss of HCC2 function had no significant effect on COX activity, the disruption of one HCC1 gene copy was enough to suppress respiration by more than half compared with the WT. Therefore, we conclude that HCC1 is essential for COX function, most likely by delivering Cu to the catalytic center. HCC2, on the other hand, seems to be involved directly or indirectly in UV-B-stress responses. SCO Synthese Cytochrom-c-Oxidase Mitochondrien Kupferchaperon COX-Komplex UV-B Stress Pflanzenwachstum Pflanzenentwicklung BN-PAGE Arabidopsis thaliana TU Dresden Publikationsfonds SCO (synthesis of cytochrome c oxidase) mitochondria copper chaperone COX complex UV-B stress plant growth and development BN-PAGE Arabidopsis thaliana Technical University Dresden Publication funds ddc:570 rvk:WA 15000
3	Ausprägung wichtiger Eigenschaften für die generative Vermehrung einer gartenbaulichen Modell-Kultur unter dem Einfluss von Genotyp und Umwelt Ghanem, Ghofran 18 November 2011 (has links) Die vorliegende Arbeit prüft bei der gärtnerischen Modell-Kultur Cyclamen den Einfluss des Genotyps (interspezifische Hybriden) auf generative Merkmale sowie bei C. persicum `Melody´ den Einfluss von Kultivierungsmaßnahmen wie die Besiedelung der Wurzeln durch einen symbiontischen Pilz (Piriformospora indica) in Kombination mit einem differenzierten Phosphor-Angebot auf vegetative und generative Merkmale: (1) Pflanzendurchmesser, (2) Blühzeitpunkt und Blütenanzahl, (3) Anzahl Samenanlagen pro Fruchtknoten, (4) Vitalität von Pollen und Samenanlagen, (5) Mikrosporogenese, (6) Befruchtungsvorgang (Pollenschlauchwachstum, Anteil Fruchtknoten mit Pollenschläuchen, Anzahl Pollenschläuche im Griffel und Penetration der Pollenschläuche in die Micropyle), (7) abortierte Blüten nach der Bestäubung (8) Samenbildung und (9) Samenanzahl. / The present paper investigates Cyclamen as an horticultural model-culture. A main Focus is on the characteristics of the Cyclamen genotype, notably with interspecific hybrids. Further, Cyclamen persicum cv. served as a model to analyse effects on parameters of pollination, seed development and number of ovules per ovary, which are caused by a root colonization of the seed bearer with the symbiotic fungus Piriformospora indica (Piri) in combination with a differentiated phosphorus supply. In this regard, plant diameter, flowering time and flower number, the viability of pollen and ovules, the microsporogenesis, the growth of pollen tubes, the seed formation and the seed count were considered among important parameters of pollination and seed development. Pollen Vitalität Interspezifische Cyclamen-Hybriden Cyclamen persicum Piriformospora indica Phosphor-Düngung Samenanlagen Mikrosporogenese Pollenschlauchwachstum Pflanzenentwicklung Flowcytometrie Samenbildung Samenertrag flow cytometry pollen Interspecific Cyclamen Hybrids Cyclamen persicum Piriformospora indica phosphorus fertilization viability ovules microsporogenesis pollen tube growth plant development seed formation seed set 630 Landwirtschaft, Veterinärmedizin 39 Landwirtschaft, Garten ZC 52000 ZC 65200 ddc:630
4	Divergent functions of the Arabidopsis mitochondrial SCO proteins: HCC1 is essential for COX activity while HCC2 is involved in the UV-B stress response Steinebrunner, Iris, Gey, Uta, Andres, Manuela, Garcia, Lucila, Gonzalez, Daniel H. 11 July 2014 (has links) The two related putative cytochrome c oxidase (COX) assembly factors HCC1 and HCC2 from Arabidopsis thaliana are Homologs of the yeast Copper Chaperones Sco1p and Sco2p. The hcc1 null mutation was previously shown to be embryo lethal while the disruption of the HCC2 gene function had no obvious effect on plant development, but increased the expression of stress-responsive genes. Both HCC1 and HCC2 contain a thioredoxin domain, but only HCC1 carries a Cu-binding motif also found in Sco1p and Sco2p. In order to investigate the physiological implications suggested by this difference, various hcc1 and hcc2 mutants were generated and analyzed. The lethality of the hcc1 knockout mutation was rescued by complementation with the HCC1 gene under the control of the embryo-specific promoter ABSCISIC ACID INSENSITIVE 3. However, the complemented seedlings did not grow into mature plants, underscoring the general importance of HCC1 for plant growth. The HCC2 homolog was shown to localize to mitochondria like HCC1, yet the function of HCC2 is evidently different, because two hcc2 knockout lines developed normally and exhibited only mild growth suppression compared with the wild type (WT). However, hcc2 knockouts were more sensitive to UV-B treatment than the WT. Complementation of the hcc2 knockout with HCC2 rescued the UV-B-sensitive phenotype. In agreement with this, exposure of wild-type plants to UV-B led to an increase of HCC2 transcripts. In order to corroborate a function of HCC1 and HCC2 in COX biogenesis, COX activity of hcc1 and hcc2 mutants was compared. While the loss of HCC2 function had no significant effect on COX activity, the disruption of one HCC1 gene copy was enough to suppress respiration by more than half compared with the WT. Therefore, we conclude that HCC1 is essential for COX function, most likely by delivering Cu to the catalytic center. HCC2, on the other hand, seems to be involved directly or indirectly in UV-B-stress responses. info:eu-repo/classification/ddc/570 ddc:570

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