SEEDS. Physiology of Development and Germination. J. Derek Bewley

Transcription

1 SEEDS Physiology of Development and Germination J. Derek Bewley Plant Physiology Research Group Department of Biology University of Calgary Calgary, Alberta, Canada and Michael Black Department of Biology Queen Elizabeth College University of London London, England Plenum Press New York and London

2 Chapter 1 Seeds: Germination, Structure, and Composition 1.1. Introduction Seed Germination Some General Features Measurement of Germination Seed Structure Embryo Nonembryonic Storage Tissues Seed Coat Testa Seed Storage Reserves Carbohydrates Fats and Oils (Lipids) Proteins Phytin Other Constituents '. > 25 Chapter 2 Seed Development and Maturation 2.1. Embryogeny and Storage Tissue Formation Source of Assimilates for Grain and Seed Filling Cereals Legumes Translocation of Assimilates into the Developing Seed 38

3 viii Contents 2.3. Deposition of Reserves within Storage Tissues Starch Synthesis Deposition of Polymeric Carbohydrates Other than Starch Fat (Oil) Synthesis Storage Protein Synthesis Cereals Dicots Phytin Deposition Deposition of Several Reserves Correlative Patterns Maturation Drying The Effects of Water Loss on Developmental Events Hormones in the Developing Seed Composition and Location Auxins Gibberellins Cytokinins ABA Possible Roles of Seed Hormones Seed Growth and Development Fruit Growth and Development Hormones for Germination and Growth Other Effects of the Seed Hormones 83 Chapter 3 Storage, Imbibition, and Germination 3.1. The Longevity of Seeds ;; Viability of Seeds in Storage The Relationship between Temperature and Moisture during Storage Other Factors That Affect Seed Viability during Storage Cultivar and Harvest Variability Pre- and Postharvest Conditions : Oxygen Pressure during Storage Fluctuating Storage Conditions Microflora and Seed Deterioration Seed Storage Facilities Recalcitrant Seeds 100

4 ix 3.3. The Biochemical Basis of Deterioration of Orthodox Seeds Respiration and ATP Synthesis Protein and Ribonucleic Acid Synthesis Damage to Chromosomes and DNA Aging and the Deterioration of Membranes Metabolism of the Dry Seed Imbibition Uptake of Water from the Soil Kinetics of Water Uptake by Seeds Soaking Injury, Solute Leakage, and Imbibitional Chilling Damage The Completion of Germination: Radicle Elongation and Its Control Seedling Development 128 Chapter 4 Cellular Events during Germination and Seedling Growth 4.1. Respiration Oxygen Consumption Pathways, Intermediates, and Products Respiration during Imbibition and Germination Phase I Phase II Phase III Phase IV Mitochondrial Development and Oxidative Phosphorylation Site of ATP Production during Early Imbibition The Route of Electrons between Substrate and Molecular Oxygen \ Mitochondrial Development in Imbibed Seeds ATP Synthesis and Adenylate Energy Charge during Germination The Synthesis and Utilization of Reducing Power: Pyridine Nucleotides Respiration under Anaerobic Conditions Protein and Ribonucleic Acid Synthesis The Mechanism and Measurement of Protein Synthesis Protein Synthesis during Germination and Its Dependence on Messenger RNA Synthesis 158

5 Ribosomal and Transfer RNA Synthesis Enzymes and Precursors of RNA Synthesis Protein and RNA Synthesis in Storage Tissues DNA Synthesis and Cell Division 168 Chapter 5 Dormancy and the Control of Germination 5.1. Introduction Internal Controls Dormancy Its Biological Role Categories of Dormancy Mechanism of Dormancy Embryo Dormancy The Inherent Constraints Coat-Imposed Dormancy The Constraints Interference with Water Uptake Mechanical Restraint Interference with Gas Exchange Prevention of Exit of Inhibitors Supply of Inhibitors to the Embryo Coat-Imposed Dormancy A Summary Embryonic Inadequacy The Causes Metabolism of Dormant Seeds Membranes and Dormancy Development of Dormancy When Does Primary Dormancy Occur? Genetic Control of Dormancy Correlative Effects in Dormancy ; Dormancy Induction by Inhibitors The Environment in Dormancy Inception Development of Hard Coats Secondary Dormancy The External Controls The Release from Dormancy Afterripening Low Temperatures (Chilling) Other Effects of Temperatures on Dormancy Light a. Action Spectra and Phytochrome b. Photoequilibria 212

6 xi c. Where Is Phytochrome Located? d. Photoconversions of Phytochrome e. Phytochrome The Sensor Seeds with Impermeable Coats Breaking of Dormancy by Chemicals The Mechanism of Dormancy Release Hormones in Dormancy Breakage Dormancy Breakage and Metabolism Dormancy Breakage and Cell Enlargement Environmental Control of Germination Effects of Light Inhibition by Short Periods of Far-Red Light Effects of Temperature Water Stress Oxygen and Carbon Dioxide 233 Chapter 6 Some Ecophysiological Aspects of Germination 6.1. Introduction Seed Burial The Seed Bank Light and Seed Burial Germination under Leaf Shade Temperature Water Interactions Secondary Dormancy Germination, Plant Distribution, and Plant Origin 248 Chapter 7 Mobilization of Stored Seed Reserves 7.1. Stored Carbohydrate Catabolism Pathways of Starch Catabolism Synthesis of Sucrose Mobilization of Stored Carbohydrate Reserves in Cereals The Embryo Reserves The Endosperm Reserves The Fate of the Products of Starch Hydrolysis 263

7 xii Contents 7.3. Mobilization of Stored Carbohydrate Reserves in Legumes Nonendospermic Legumes Endospermic Legumes Mannan-Containing Seeds Other than Legumes Stored Lipid Catabolism General Catabolism Mobilization of Fats from Oil Bodies The Fate of Glycerol and Fatty Acids Role of the Glyoxysome, Mitochondrion, and Cytosol in Gluconeogenesis Glyoxysome Biosynthesis and Degradation Utilization of the Products of Fat Catabolism Stored Protein Catabolism General Catabolism Protein Mobilization in Cereals Protein Mobilization in Dicots Utilization of the Liberated Amino Acids Proteinase Inhibitors Stored Phosphate Catabolism General Catabolism Phosphate Catabolism in Seeds Mobilization of Nucleic Acids from the Storage Regions. 300 Chapter 8 Control of the Mobilization of Stored Reserves 8.1. Control of Reserve Mobilization in Cereals Gibberellin and the Induction of a-amylase Synthesis in Barley Regulation of a-amylase Production within the Intact Grain Regulation of Other Hydrolases in the Barley Aleurone Layer Gibberellin Induction of Hydrolytic Enzymes in Other Cereals Control Processes in Other Seeds When Are the Mobilizing Enzymes Produced? Regulation of Mobilization 319

8 xiii Mode of Regulation by the Axis Hormonal Control by the Axis The Axis as a Sink 325 Chapter 9 Seeds and Germination: Some Agricultural and Industrial Aspects 9.1. Introduction, Malting Preharvest Sprouting Conditions under Which Preharvest Sprouting Occurs The Physiology of Preharvest Sprouting in Wheat Genetic Conservation Seed Gene Banks Enhancement of Seed Germination by Osmotic Stress and Dehydration Treatments Osmotic Stress Dehydration-Rehydration 345 Index 349