Beschreibung
Inhaltsangabe1. Viability and Longevity.- 1.1 The Life-Span of Seeds.- 1.1.1 The Oldest Seeds - from the Pharoah's Tomb to the Incendiary Bomb.- 1.1.2 Life-Span of Seeds Buried in Soil.- 1.2 Viability of Seeds in Storage.- 1.2.1 Recalcitrant Seeds.- 1.2.2 Orthodox Seeds.- 1.2.3 The Basic Viability Equations.- 1.2.4 Improved Viability Equations.- 1.3 Microflora and Seed Deterioration.- 1.4 The Biochemical Basis of Deterioration.- 1.5 Respiration and the Production of ATP.- 1.5.1 Non-Viable Seeds and Embryos.- 1.5.2 Seed Populations with Reduced Viability and/or Vigour.- 1.6 Protein and RNA Synthesis.- 1.7 Chromosome Aberrations and DNA Synthesis.- 1.7.1 Chromosome Damage and Repair.- 1.8 Metabolism of Dry Seeds.- 1.9 Changes in Food Reserves.- 1.10 Free Fatty Acids and Interference with Metabolism.- 1.11 Membrane Changes and Leakage.- 1.11.1 Leakage of Metabolites and Integrity of the Bounding Membranes.- 1.11.2 The Nature and Cause of Membrane Damage.- Some Works of General Interest.- References.- 2. Dormancy.- 2.1 What is Dormancy?.- 2.1.1 Categories of Dormancy.- 2.1.2 Biological Significance of Seed Dormancy.- 2.1.3 Dormancy in Cultivated Plants.- 2.1.4 Polymorphism and Heteroblasty.- 2.2 Dormancy Mechanisms.- 2.3 Embryo Dormancy.- 2.3.1 Control Mechanisms in Embryo Dormancy.- 2.3.2 The Role of the Cotyledons.- 2.3.3 The Role of Inhibitors.- 2.3.4 Embryo Immaturity.- 2.4 Coat-imposed Dormancy.- 2.4.1 Interference with Water Uptake.- 2.4.2 Interference with Gaseous Exchange.- 2.4.3 Inhibitors in the Coat.- 2.4.4 Prevention of the Escape of Inhibitors.- 2.4.5 The Coat as a Light Filter.- 2.4.6 Mechanical Restraint.- 2.5 Two Case Histories.- 2.5.1 Sinapis arvensis (Charlock).- 2.5.2 Xanthium pennsylvanicum (Cocklebur).- 2.6 Coat-imposed Dormancy - a Retrospective View.- 2.7 Relationships Between Coat-imposed and Embryo Dormancy.- 2.8 The Onset of Dormancy.- 2.8.1 Timing.- 2.8.2 Control.- 2.8.3 The Genetic Factor.- 2.8.4 Environmental Factors.- 2.8.5 Correlative Effects.- 2.8.6 Hormones.- 2.8.7 Secondary or Induced Dormancy.- 2.8.8 The Development of Hard Coats.- 2.9 Endogenous Germination Inhibitors.- 2.9.1 Chemical Nature of Inhibitors.- Some Works of General Interest.- References.- 3. The Release from Dormancy.- 3.1 Light and Phytochrome.- 3.2 The Phytochrome System.- 3.2.1 Spectral Sensitivity and Photoreversibility.- 3.2.2 Energies for Photoconversion.- 3.2.3 The Escape Time.- 3.2.4 Phytochrome Photoequilibria.- 3.2.5 Chemistry of Phytochrome.- 3.2.6 The Pathway of Phytochrome Photoconversion.- 3.2.7 The State of Phytochrome in Seeds.- 3.2.8 Seed Hydration and Sensitivity to Light.- 3.2.9 Reversion of Pfr in Darkness.- 3.2.10 Thermal Processes Connected with Phytochrome Action.- 3.2.11 Phytochrome Location and the Photosensitive Site.- 3.3 Phytochrome - an Overview.- 3.4 Blue Light Effects.- 3.5 Response Types.- 3.6 Temperature and the Action of Light.- 3.6.1 Constant Temperature.- 3.6.2 Temperature Alternations and Shifts.- 3.6.3 Chilling.- 3.7 Temperature and the Release from Dormancy.- 3.8 Termination of Dormancy by Temperature Alternations and Shifts.- 3.9 Termination of Dormancy by Low Temperature.- 3.9.1 Response Types.- 3.9.2 Temperature and Time Requirements.- 3.10 Termination of Dormancy by High Temperature.- 3.11 Loss of Dormancy in Dry Seeds - After-ripening.- 3.11.1 Moisture Content.- 3.11.2 Temperature.- 3.11.3 Oxygen.- 3.12 Finale - Replacements and Interactions.- 3.13 Hard-coated Seeds.- 3.14 Removal of Dormancy by Chemicals.- 3.14.1 Growth Regulators.- 3.14.2 Gibberellins.- 3.14.3 Cytokinins.- 3.14.4 Ethylene.- 3.14.5 Plant and Fungal Products.- 3.14.6 Respiratory Inhibitors.- 3.14.7 Oxidants.- 3.14.8 Nitrogenous Compounds.- 3.14.9 Sulfhydryl Compounds.- 3.14.10 Various Other Chemicals Including Anaesthetics.- Some Works of General Interest.- References.- 4. The Control of Dormancy.- 4.1 Introduction.- 4.2 Dormancy - Events and Causes.- 4.2.1 Metabolism of Dormant and After-ripened Seeds.- 4.2.2 Dormancy and Maturation
