Adaptation an pflanzliche Pyrrolizidinalkaloidebei phytophagen Käfern (Coleoptera, Chrysomelidae)im Fachbereich Biologie derUniversität Hamburg eingereichte Dissertationzur Erlangung des DoktorgradesvonIngo Narberhausaus AachenHamburg 2004Tag der Disputation: 30.04.2004 Gutachter: Prof. Dr. S. Dobler GInhalt1 Einführung 72 Uptake and metabolism of pyrrolizidine alkaloids in Longitarsus flea beetles(Coleoptera: Chrysomelidae) adapted and non adapted to alkaloid containinghost plants 122.1 Summary 122.2 Introduction 122.3 Material and Methods 142.4 Results 182.5 Discussion 243 Time course of pyrrolizidine alkaloid sequestration in Longitarsus fleabeetles (Coleoptera, Chrysomelidae) 273.1 Summary 273.2 Introduction 273.3 Material and Methods 293.4 Results 313.5 Discussion 354 Direct evidence for membrane transport of host plant derived pyrrolizidinealkaloid N-oxides in two leaf beetle genera 384.1 Summary 384.2 Introduction 384.3 Material and Methods 414.4 Results 464.5 Discussion 545 Pyrrolizidine alkaloids on three trophic levels – evidence for toxic anddeterrent effects on phytophages and predators 595.1 Summary 595.2 Introduction 595.3 Material and Methods 615.4 Results and Discussion 636 Abschliessende Diskussion 676.1 Speicherung und Metabolisierung von PAs bei Longitarsus 676.2 Membran-Carrier für PAs 696.3 Strategien der PA-Sequestration im Vergleich 706.