UV-B Radiation (eBook, PDF)
From Environmental Stressor to Regulator of Plant Growth
Redaktion: Singh, Vijay Pratap; Parihar, Parul; Prasad, Sheo Mohan; Singh, Samiksha
Alle Infos zum eBook verschenken
UV-B Radiation (eBook, PDF)
From Environmental Stressor to Regulator of Plant Growth
Redaktion: Singh, Vijay Pratap; Parihar, Parul; Prasad, Sheo Mohan; Singh, Samiksha
- Format: PDF
- Merkliste
- Auf die Merkliste
- Bewerten Bewerten
- Teilen
- Produkt teilen
- Produkterinnerung
- Produkterinnerung
Hier können Sie sich einloggen
Bitte loggen Sie sich zunächst in Ihr Kundenkonto ein oder registrieren Sie sich bei bücher.de, um das eBook-Abo tolino select nutzen zu können.
Ultraviolet-B (UV-B) is electromagnetic radiation coming from the sun, with a medium wavelength which is mostly absorbed by the ozone layer. The biological effects of UV-B are greater than simple heating effects, and many practical applications of UV-B radiation derive from its interactions with organic molecules. It is considered particularly harmful to the environment and living things, but what have scientific studies actually shown?
UV-B Radiation: From Environmental Stressor to Regulator of Plant Growth presents a comprehensive overview of the origins, current state, and future…mehr
- Geräte: PC
- mit Kopierschutz
- eBook Hilfe
- Größe: 8.48MB
- Responses of Plants to UV-B Radiation (eBook, PDF)113,95 €
- UV-B Radiation and Crop Growth (eBook, PDF)161,95 €
- Michael WinkAnnual Plant Reviews, Volume 39, Functions and Biotechnology of Plant Secondary Metabolites (eBook, PDF)167,99 €
- Plant Analysis Procedures (eBook, PDF)73,95 €
- UV-B and Biosphere (eBook, PDF)113,95 €
- Reactive Oxygen Species in Plants (eBook, PDF)170,99 €
- Physiology of Salt Stress in Plants (eBook, PDF)159,99 €
-
-
-
UV-B Radiation: From Environmental Stressor to Regulator of Plant Growth presents a comprehensive overview of the origins, current state, and future horizons of scientific research on ultraviolet-B radiation and its perception in plants. Chapters explore all facets of UV-B research, including the basics of how UV-B's shorter wavelength radiation from the sun reaches the Earth's surface, along with its impact on the environment's biotic components and on human biological systems. Chapters also address the dramatic shift in UV-B research in recent years, reflecting emerging technologies, showing how historic research which focused exclusively on the harmful environmental effects of UV-B radiation has now given way to studies on potential benefits to humans. Topics include:
- UV-B and its climatology
- UV-B and terrestrial ecosystems
- Plant responses to UV-B stress
- UB- B avoidance mechanisms
- UV-B and production of secondary metabolites
- Discovery of UVR8
Timely and important, UV-B Radiation: From Environmental Stressor to Regulator of Plant Growth is an invaluable resource for environmentalists, researchers and students who are into the state-of-the-art research being done on exposure to UV-B radiation.
Dieser Download kann aus rechtlichen Gründen nur mit Rechnungsadresse in D ausgeliefert werden.
- Produktdetails
- Verlag: John Wiley & Sons
- Erscheinungstermin: 2. Februar 2017
- Englisch
- ISBN-13: 9781119143635
- Artikelnr.: 47757959
- Verlag: John Wiley & Sons
- Erscheinungstermin: 2. Februar 2017
- Englisch
- ISBN-13: 9781119143635
- Artikelnr.: 47757959
- Herstellerkennzeichnung Die Herstellerinformationen sind derzeit nicht verfügbar.
B Research in Plant Science 1 Rachana Singh, Parul Parihar, Samiksha Singh, MPVVB Singh, Vijay Pratap Singh and Sheo Mohan Prasad 1.1 The Historical Background 1 1.2 Biologically Effective Irradiance 2 1.3 UV
B
induced Effects in Plants 3 1.4 Conclusion and Future Prospects 5 Acknowledgements 6 References 6 2 Stimulation of Various Phenolics in Plants Under Ambient UV
B Radiation 9 Marija Vidovi
, Filis Morina and Sonja Veljovi
Jovanovi
2.1 Introduction 9 2.2 UV
B Radiation 10 2.2 Phenolics 12 2.2.1 Chemistry of Phenolic Compounds 13 2.2.2 Biosynthesis and Subcellular Localization of Phenolics 13 2.2.3 Functions of Phenolic Compounds Depend on Their Localization 15 2.4 UV
B Radiation Stimulates Phenolic Induction 18 2.4.1 Mechanisms of UV
B Perception 18 2.4.2 UV
B
Induced Accumulation of Phenolic Compounds 20 2.4.1 Interactive Effects of UV
B with UV
A Radiation and PAR on Phenolics Accumulation 28 2.4.2 Interactive Effects of UV
B with other Environmental Factors on Phenolics Accumulation 30 2.5 UV
B
Induced Photomorphological Responses 31 2.5.1 Connection Between UV
B
Induced Morphological Responses and Phenolics 31 2.5.2 Effect of UV
B Radiation on Root Morphology in Relation to Phenolics 32 2.6 Photosynthesis Under UV
B Radiation 33 2.6.1 Interplay of Phenolics and Photosynthesis Under UV
B Radiation 34 2.7 UV
B Radiation Induces Phenolics Accumulation in Fruits 37 2.8 Conclusions and Future Perspectives 38 References 39 3 UV
B Radiation: A Reassessment of its Impact on Plants and Crops 57 Krystyna
uk
Göaszewska 3.1 Introduction 57 3.2 Plant Production 58 3.3 Plant protection Against UVB 60 References 60 4 Interaction of UV
B with the Terrestrial Ecosystem 65 Rohit Kumar Mishra, Sanjesh Tiwari and Sheo Mohan Prasad 4.1 Introduction 65 4.2 Growth and Development 66 4.3 Secondary Metabolites 67 4.4 Susceptibility to Herbivorous Insects 67 4.5 Plant Sexual Reproduction 67 4.6 Genomic Level 68 4.7 Conclusion 69 References 70 5 A Review of Stress and Responses of Plants to UV
B Radiation 75 Sonika Sharma, Soumya Chatterjee, Sunita Kataria, Juhie Joshi, Sibnarayan Datta, Mohan G. Vairale and Vijay Veer 5.1 Introduction 75 5.2 Morphological and Yield Response to UV
B 76 5.3 Targets of UV
B in the Carbon Fixation Cycle 79 5.4 Photoreceptors and Signalling Pathway in Response to UV
B Radiation 80 5.5 Acclimatization and Protection in Response to UV
B 82 5.6 Oxidative Stress and Antioxidant System in Response to UV
B 82 5.7 DNA Damage and Repair Mechanism 83 5.8 Exclusion of UV Components: Experimental Approach to Study the Effect on Plants 85 5.9 Conclusion and Future Prospective 86 Acknowledgement 87 References 87 6 Oxidative Stress and Antioxidative Defence System in Plants in Response to UV
B Stress 99 Sunita Kataria 6.1 Introduction 99 6.2 Plant Protection Against UV Radiation 101 6.3 UV
B and ROS 103 6.4 UV
B and Antioxidant Enzymes 104 6.5 UV
B and Antioxidant 107 6.6 UV
B and Signalling 108 6.7 Conclusions and Perspectives 110 References 111 7 Major influence on phytochrome and photosynthetic machinery under UV
B exposure 123 Anita Singh, Gausiya Bashri and Sheo Mohan Prasad 7.1 Introduction 123 7.2 Photomorphogenesis in Higher Plants 124 7.2.1 Phytochrome system and its interaction with UV
B 124 7.2.2 Photomorphogenic responses of UV
B 125 7.2.3 UV
B signal transduction (UV
R8) 127 7.3 Effect of UV
B Exposure on Photosynthetic Machinery 128 7.3.1 Direct effects of UV
B on photosynthetic machinery 128 7.3.1.1 Effects of UV
B stress on components involved in light reaction 128 7.3.1.2 Effect of UV
B stress on photosystems and cytochrome b6/f complex 129 7.3.2 Indirect effect of UV
B stress on components involved in dark reaction 132 7.3.2.1 Impact on regulation of stomata and RuBisCO enzyme 132 7.3.3 UV
B induced ROS production in plants 133 7.3.4 Protective adaptation 133 7.4 Conclusion and Future Perspectives 135 References 136 8 UV
B Radiation
Induced Damage of Photosynthetic Apparatus of Green Leaves: Protective Strategies vis
a
vis Visible and/or UV
A Light 143 Padmanava Joshi 8.1 Introduction 143 8.2 UV
B Effects on the Photosynthetic Apparatus of Leaves 143 8.3 UV
A Effects on Photosynthetic Apparatus of Leaves (Damage and Promotion) 145 8.4 UV
A
Mediated Modulation of UV
B
Induced Damage 145 8.5 PAR
Mediated Balancing of UV
B
Induced Damage 146 8.6 Photosynthetic Adaptation and Acclimation to UV
B Radiation 146 8.7 Corroboration with Sensible Approach 147 8.8 Conclusion 149 Acknowledgements 149 References 149 9 Ultraviolet Radiation Targets in the Cellular System: Current Status and Future Directions 155 Parul Parihar, Rachana Singh, Samiksha Singh, MPVVB Singh, Vijay Pratap Singh and Sheo Mohan Prasad 9.1 Introduction 155 9.2 Absorption Characteristics of Biomolecules 156 9.3 Action Spectrum 156 9.4 Targets of UV
B 157 9.4.1 Interaction with Biomolecules 157 9.4.2 Nucleic Acids 158 9.4.3 Ribonucleic Acids 159 9.5 UV
B Interaction with Proteins 159 9.5.1 Tryptophan 160 9.5.2 Tyrosine 160 9.5.3 Phenylalanine 162 9.5.4 Histidine 162 9.6 The Photosynthetic Machinery 163 9.6.1 Photosystem I and II 164 9.6.2 The Light
Harvesting Complexes 165 9.7 Cell Division and Expansion 167 9.8 Conclusion and Future Directions 168 Acknowledgements 169 References 169 10 Silicon: A Potential Element to Combat Adverse Impact of UV
B in plants 175 Durgesh Kumar Tripathi, Shweta, Shweta Singh, Vaishali Yadav, Namira Arif, Swati Singh, Nawal Kishor Dubey and Devendra Kumar Chauhan 10.1 Introduction 175 10.2 The role of Silicon Against UV
B Exposure on Morphology of Plants 178 10.3 The defensive role of silicon against UV
B exposure on physiological and biochemical traits of plants 179 10.4 Silicon repairs anatomical structures of plants damaged by UV
B exposures 180 10.5 UV
B
induced oxidative stress and silicon supplementation in plants 181 10.6 Silicon supplementation and the status of antioxidant enzymes in plants exposed to UV
B 183 10.7 Silicon and level of phenolic compounds under UV
B stress 184 10.8 Present status and future prospectives 186 References 187 11 Sun
Screening Biomolecules in Microalgae: Role in UV
Photoprotection 197 Rajesh P Rastogi, Ravi R Sonani, Aran Incharoensakdi and Datta Madamwar 11.1 Introduction 197 11.2 Global Climate Change and UV Radiation 198 11.3 Effects of UV Radiation on Microalgae 199 11.4 UV
induced Defence Mechanisms 201 11.5 Sun
Screening Biomolecules as Key UV Photoprotectants 201 11.5.1 Mycosporine
Like Amino Acids (MAAs) 202 11.5.2 Scytonemin 204 11.6 UV
Induced Biosynthesis 206 11.7 Photoprotective Function 207 11.8 Conclusions 208 Acknowledgements 208 References 208 12 Plant Response: UB
B Avoidance Mechanisms 217 Sunil K Gupta, Marisha Sharma, Farah Deeba and Vivek Pandey 12.1 Introduction 217 12.2 Ultraviolet Radiation: Common Source, Classification and Factors 219 12.2.1 Common Sources of UV
R 219 12.2.2 Classification 219 12.2.3 Environmental Factors Affecting UV Level 220 12.3 UV
B and Human Health 220 12.3.1 Effects on the Skin 220 12.3.2 Effects on the Eyes 220 12.4 UV
B and Plant Responses 220 12.4.1 Morphological Responses 220 12.4.1.1 Visible Symptoms 220 12.4.1.2 Plant Growth and Leaf Phenology 221 12.4.1.3 Reproductive Morphology 222 12.4.1.4 UV
B
induced photomorphogenesis 222 12.4.2 Leaf Ultrastructure and Anatomy 222 12.4.3 Crop Yield 223 12.4.4 Photosynthesis 225 12.4.4.1 Pigments 225 12.4.4.2 Photosynthetic Machinery 225 12.4.5 Biochemical Responses 226 12.4.5.1 ROS Production in Plants 226 12.4.5.2 Free Radical Scavenging Mechanism 227 12.4.6 Molecular Responses 227 12.4.6.1 UV
B and Genes 227 12.4.6.2 UV and Proteins 230 12.5 UV
B Avoidance and Defence Mechanism 234 12.5.1 Avoidance at Morphological Level 234 12.5.1.1 Epicuticular Waxes 234 12.5.2 Avoidance at Biochemical Level 235 12.5.2.1 Possible Role of Pectin Endocytosis in UV
B Avoidance 235 12.5.3 Avoidance at the Molecular Level 236 12.5.3.1 DNA Repair 236 12.5.3.2 Genes and Avoidance 237 12.5.3.3 UV
B perceived by UVR8 Strongly Inhibits Shade Avoidance 237 12.5.4 UV
B and Secondary Metabolites 238 12.5.4.1 Plant Phenolics 238 12.5.4.2 Anthocyanin 239 12.5.4.3 Alkaloids 240 12.5.4.4 Isoprenoids 240 12.5.4.5 Glucosinolates 240 12.6 UV
B and its Significance 240 12.6.1 Ecological Significance 240 12.6.2 UV
B and Plant Competition 241 12.7 Conclusion 242 Acknowledgments 243 References 244 13 Impact of UV
B Exposure on Phytochrome and Photosynthetic Machinery: From Cyanobacteria to Plants 259 Shivam Yadav, Alok Kumar Shrivastava, Chhavi Agrawal, Sonia Sen, Antra Chatterjee, Shweta Rai and LC Rai 13.1 Introduction 259 13.2 Effect of UV
B Irradiation on Photosynthetic Machinery of Cyanobacteria 260 13.2.1 Pigments 260 13.2.2 Photosynthetic Electron Transport System 261 13.2.3 Photophosphorylation and CO2 fixation 262 13.3 Effect of UV
B Irradiation on Photosynthetic Machinery of Algae 262 13.4 Effect of UV
B Irradiation on Photosynthetic Machinery of Higher Plants 264 13.4.1 Pigments 264 13.4.1.1 Phytochrome 264 13.4.1.2 Chlorophylls, carotenoids and other pigments 265 13.4.2 Photosystem II 265 13.4.2.1 Oxygen
evolving complex 266 13.4.2.2 Plastoquinones and redox
active tyrosines 266 13.4.2.3 D1 and D2 proteins 267 13.4.3 Photosystem I 267 13.4.4 Cytochrome B6F complex, ATP synthase and RuBisCO 267 13.4.5 Net photosynthesis 268 13.5 Conclusion and future perspective 268 Acknowledgements 268 References 269 14 Discovery of UVR8: New Insight in UV
B Research 279 ShivamYadav and Neelam Atri 14.1 Introduction 279 14.2 Photoperception in Plants 280 14.3 Discovery of UVR8: UV
B Photoreceptor 280 14.4 UVR8 Structure 281 14.4.1 Salt Bridge Interactions Mediate UVR8 Dimerization 281 14.4.2 Chromophore and Key Tryptophan Residues 281 14.5 Physiological Roles of UVR8 283 14.5.1 Photomorphogenic Response Regulation by UVR8 283 14.5.2 Regulation of Flavonoid Biosynthesis 284 14.5.3 Plant
Pathogen and Plant
Herbivore Interactions 284 14.6 Conclusion and Future Perspectives 284 References 285 15 UVR8 Signalling, Mechanism and Integration with other Pathways 289 Antra Chatterjee, Alok Kumar Shrivastava, Sonia Sen, Shweta Rai, Shivam Yadav and LC Rai 15.1 Introduction 289 15.2 UVR8
Arbitrated Signalling 290 15.2.1 Constitutively Photomorphogenic 1 (COP1) 290 15.2.2 Elongated Hypocotyl 5 (HY5) and HYH 291 15.2.3 Repressor of UV
B Photomorphogenesis 1 (RUP1) and RUP2 292 15.3 Molecular Mechanism of Photoreceptor
Mediated Signalling 293 15.4 UVR8 Involvements in Different Pathways 296 15.4.1 Protection from PhotöInhibition and Photo Oxidative Stress 297 15.4.2 Flavonoid and Alkaloid Pathways 298 15.4.3 DNA Damage Repair 299 15.4.4 Defence Against Pathogens 299 15.4.5 Inhibition of Plant Shade Avoidance 300 15.4.6 Regulation of Leaf Morphogenesis 300 15.4.7 Regulation of Root Growth and Development 300 15.4.8 Circadian Clock 301 15.5 Conclusion and Future Perspectives 301 Acknowledgements 302 References 302 Index 309
B Research in Plant Science 1 Rachana Singh, Parul Parihar, Samiksha Singh, MPVVB Singh, Vijay Pratap Singh and Sheo Mohan Prasad 1.1 The Historical Background 1 1.2 Biologically Effective Irradiance 2 1.3 UV
B
induced Effects in Plants 3 1.4 Conclusion and Future Prospects 5 Acknowledgements 6 References 6 2 Stimulation of Various Phenolics in Plants Under Ambient UV
B Radiation 9 Marija Vidovi
, Filis Morina and Sonja Veljovi
Jovanovi
2.1 Introduction 9 2.2 UV
B Radiation 10 2.2 Phenolics 12 2.2.1 Chemistry of Phenolic Compounds 13 2.2.2 Biosynthesis and Subcellular Localization of Phenolics 13 2.2.3 Functions of Phenolic Compounds Depend on Their Localization 15 2.4 UV
B Radiation Stimulates Phenolic Induction 18 2.4.1 Mechanisms of UV
B Perception 18 2.4.2 UV
B
Induced Accumulation of Phenolic Compounds 20 2.4.1 Interactive Effects of UV
B with UV
A Radiation and PAR on Phenolics Accumulation 28 2.4.2 Interactive Effects of UV
B with other Environmental Factors on Phenolics Accumulation 30 2.5 UV
B
Induced Photomorphological Responses 31 2.5.1 Connection Between UV
B
Induced Morphological Responses and Phenolics 31 2.5.2 Effect of UV
B Radiation on Root Morphology in Relation to Phenolics 32 2.6 Photosynthesis Under UV
B Radiation 33 2.6.1 Interplay of Phenolics and Photosynthesis Under UV
B Radiation 34 2.7 UV
B Radiation Induces Phenolics Accumulation in Fruits 37 2.8 Conclusions and Future Perspectives 38 References 39 3 UV
B Radiation: A Reassessment of its Impact on Plants and Crops 57 Krystyna
uk
Göaszewska 3.1 Introduction 57 3.2 Plant Production 58 3.3 Plant protection Against UVB 60 References 60 4 Interaction of UV
B with the Terrestrial Ecosystem 65 Rohit Kumar Mishra, Sanjesh Tiwari and Sheo Mohan Prasad 4.1 Introduction 65 4.2 Growth and Development 66 4.3 Secondary Metabolites 67 4.4 Susceptibility to Herbivorous Insects 67 4.5 Plant Sexual Reproduction 67 4.6 Genomic Level 68 4.7 Conclusion 69 References 70 5 A Review of Stress and Responses of Plants to UV
B Radiation 75 Sonika Sharma, Soumya Chatterjee, Sunita Kataria, Juhie Joshi, Sibnarayan Datta, Mohan G. Vairale and Vijay Veer 5.1 Introduction 75 5.2 Morphological and Yield Response to UV
B 76 5.3 Targets of UV
B in the Carbon Fixation Cycle 79 5.4 Photoreceptors and Signalling Pathway in Response to UV
B Radiation 80 5.5 Acclimatization and Protection in Response to UV
B 82 5.6 Oxidative Stress and Antioxidant System in Response to UV
B 82 5.7 DNA Damage and Repair Mechanism 83 5.8 Exclusion of UV Components: Experimental Approach to Study the Effect on Plants 85 5.9 Conclusion and Future Prospective 86 Acknowledgement 87 References 87 6 Oxidative Stress and Antioxidative Defence System in Plants in Response to UV
B Stress 99 Sunita Kataria 6.1 Introduction 99 6.2 Plant Protection Against UV Radiation 101 6.3 UV
B and ROS 103 6.4 UV
B and Antioxidant Enzymes 104 6.5 UV
B and Antioxidant 107 6.6 UV
B and Signalling 108 6.7 Conclusions and Perspectives 110 References 111 7 Major influence on phytochrome and photosynthetic machinery under UV
B exposure 123 Anita Singh, Gausiya Bashri and Sheo Mohan Prasad 7.1 Introduction 123 7.2 Photomorphogenesis in Higher Plants 124 7.2.1 Phytochrome system and its interaction with UV
B 124 7.2.2 Photomorphogenic responses of UV
B 125 7.2.3 UV
B signal transduction (UV
R8) 127 7.3 Effect of UV
B Exposure on Photosynthetic Machinery 128 7.3.1 Direct effects of UV
B on photosynthetic machinery 128 7.3.1.1 Effects of UV
B stress on components involved in light reaction 128 7.3.1.2 Effect of UV
B stress on photosystems and cytochrome b6/f complex 129 7.3.2 Indirect effect of UV
B stress on components involved in dark reaction 132 7.3.2.1 Impact on regulation of stomata and RuBisCO enzyme 132 7.3.3 UV
B induced ROS production in plants 133 7.3.4 Protective adaptation 133 7.4 Conclusion and Future Perspectives 135 References 136 8 UV
B Radiation
Induced Damage of Photosynthetic Apparatus of Green Leaves: Protective Strategies vis
a
vis Visible and/or UV
A Light 143 Padmanava Joshi 8.1 Introduction 143 8.2 UV
B Effects on the Photosynthetic Apparatus of Leaves 143 8.3 UV
A Effects on Photosynthetic Apparatus of Leaves (Damage and Promotion) 145 8.4 UV
A
Mediated Modulation of UV
B
Induced Damage 145 8.5 PAR
Mediated Balancing of UV
B
Induced Damage 146 8.6 Photosynthetic Adaptation and Acclimation to UV
B Radiation 146 8.7 Corroboration with Sensible Approach 147 8.8 Conclusion 149 Acknowledgements 149 References 149 9 Ultraviolet Radiation Targets in the Cellular System: Current Status and Future Directions 155 Parul Parihar, Rachana Singh, Samiksha Singh, MPVVB Singh, Vijay Pratap Singh and Sheo Mohan Prasad 9.1 Introduction 155 9.2 Absorption Characteristics of Biomolecules 156 9.3 Action Spectrum 156 9.4 Targets of UV
B 157 9.4.1 Interaction with Biomolecules 157 9.4.2 Nucleic Acids 158 9.4.3 Ribonucleic Acids 159 9.5 UV
B Interaction with Proteins 159 9.5.1 Tryptophan 160 9.5.2 Tyrosine 160 9.5.3 Phenylalanine 162 9.5.4 Histidine 162 9.6 The Photosynthetic Machinery 163 9.6.1 Photosystem I and II 164 9.6.2 The Light
Harvesting Complexes 165 9.7 Cell Division and Expansion 167 9.8 Conclusion and Future Directions 168 Acknowledgements 169 References 169 10 Silicon: A Potential Element to Combat Adverse Impact of UV
B in plants 175 Durgesh Kumar Tripathi, Shweta, Shweta Singh, Vaishali Yadav, Namira Arif, Swati Singh, Nawal Kishor Dubey and Devendra Kumar Chauhan 10.1 Introduction 175 10.2 The role of Silicon Against UV
B Exposure on Morphology of Plants 178 10.3 The defensive role of silicon against UV
B exposure on physiological and biochemical traits of plants 179 10.4 Silicon repairs anatomical structures of plants damaged by UV
B exposures 180 10.5 UV
B
induced oxidative stress and silicon supplementation in plants 181 10.6 Silicon supplementation and the status of antioxidant enzymes in plants exposed to UV
B 183 10.7 Silicon and level of phenolic compounds under UV
B stress 184 10.8 Present status and future prospectives 186 References 187 11 Sun
Screening Biomolecules in Microalgae: Role in UV
Photoprotection 197 Rajesh P Rastogi, Ravi R Sonani, Aran Incharoensakdi and Datta Madamwar 11.1 Introduction 197 11.2 Global Climate Change and UV Radiation 198 11.3 Effects of UV Radiation on Microalgae 199 11.4 UV
induced Defence Mechanisms 201 11.5 Sun
Screening Biomolecules as Key UV Photoprotectants 201 11.5.1 Mycosporine
Like Amino Acids (MAAs) 202 11.5.2 Scytonemin 204 11.6 UV
Induced Biosynthesis 206 11.7 Photoprotective Function 207 11.8 Conclusions 208 Acknowledgements 208 References 208 12 Plant Response: UB
B Avoidance Mechanisms 217 Sunil K Gupta, Marisha Sharma, Farah Deeba and Vivek Pandey 12.1 Introduction 217 12.2 Ultraviolet Radiation: Common Source, Classification and Factors 219 12.2.1 Common Sources of UV
R 219 12.2.2 Classification 219 12.2.3 Environmental Factors Affecting UV Level 220 12.3 UV
B and Human Health 220 12.3.1 Effects on the Skin 220 12.3.2 Effects on the Eyes 220 12.4 UV
B and Plant Responses 220 12.4.1 Morphological Responses 220 12.4.1.1 Visible Symptoms 220 12.4.1.2 Plant Growth and Leaf Phenology 221 12.4.1.3 Reproductive Morphology 222 12.4.1.4 UV
B
induced photomorphogenesis 222 12.4.2 Leaf Ultrastructure and Anatomy 222 12.4.3 Crop Yield 223 12.4.4 Photosynthesis 225 12.4.4.1 Pigments 225 12.4.4.2 Photosynthetic Machinery 225 12.4.5 Biochemical Responses 226 12.4.5.1 ROS Production in Plants 226 12.4.5.2 Free Radical Scavenging Mechanism 227 12.4.6 Molecular Responses 227 12.4.6.1 UV
B and Genes 227 12.4.6.2 UV and Proteins 230 12.5 UV
B Avoidance and Defence Mechanism 234 12.5.1 Avoidance at Morphological Level 234 12.5.1.1 Epicuticular Waxes 234 12.5.2 Avoidance at Biochemical Level 235 12.5.2.1 Possible Role of Pectin Endocytosis in UV
B Avoidance 235 12.5.3 Avoidance at the Molecular Level 236 12.5.3.1 DNA Repair 236 12.5.3.2 Genes and Avoidance 237 12.5.3.3 UV
B perceived by UVR8 Strongly Inhibits Shade Avoidance 237 12.5.4 UV
B and Secondary Metabolites 238 12.5.4.1 Plant Phenolics 238 12.5.4.2 Anthocyanin 239 12.5.4.3 Alkaloids 240 12.5.4.4 Isoprenoids 240 12.5.4.5 Glucosinolates 240 12.6 UV
B and its Significance 240 12.6.1 Ecological Significance 240 12.6.2 UV
B and Plant Competition 241 12.7 Conclusion 242 Acknowledgments 243 References 244 13 Impact of UV
B Exposure on Phytochrome and Photosynthetic Machinery: From Cyanobacteria to Plants 259 Shivam Yadav, Alok Kumar Shrivastava, Chhavi Agrawal, Sonia Sen, Antra Chatterjee, Shweta Rai and LC Rai 13.1 Introduction 259 13.2 Effect of UV
B Irradiation on Photosynthetic Machinery of Cyanobacteria 260 13.2.1 Pigments 260 13.2.2 Photosynthetic Electron Transport System 261 13.2.3 Photophosphorylation and CO2 fixation 262 13.3 Effect of UV
B Irradiation on Photosynthetic Machinery of Algae 262 13.4 Effect of UV
B Irradiation on Photosynthetic Machinery of Higher Plants 264 13.4.1 Pigments 264 13.4.1.1 Phytochrome 264 13.4.1.2 Chlorophylls, carotenoids and other pigments 265 13.4.2 Photosystem II 265 13.4.2.1 Oxygen
evolving complex 266 13.4.2.2 Plastoquinones and redox
active tyrosines 266 13.4.2.3 D1 and D2 proteins 267 13.4.3 Photosystem I 267 13.4.4 Cytochrome B6F complex, ATP synthase and RuBisCO 267 13.4.5 Net photosynthesis 268 13.5 Conclusion and future perspective 268 Acknowledgements 268 References 269 14 Discovery of UVR8: New Insight in UV
B Research 279 ShivamYadav and Neelam Atri 14.1 Introduction 279 14.2 Photoperception in Plants 280 14.3 Discovery of UVR8: UV
B Photoreceptor 280 14.4 UVR8 Structure 281 14.4.1 Salt Bridge Interactions Mediate UVR8 Dimerization 281 14.4.2 Chromophore and Key Tryptophan Residues 281 14.5 Physiological Roles of UVR8 283 14.5.1 Photomorphogenic Response Regulation by UVR8 283 14.5.2 Regulation of Flavonoid Biosynthesis 284 14.5.3 Plant
Pathogen and Plant
Herbivore Interactions 284 14.6 Conclusion and Future Perspectives 284 References 285 15 UVR8 Signalling, Mechanism and Integration with other Pathways 289 Antra Chatterjee, Alok Kumar Shrivastava, Sonia Sen, Shweta Rai, Shivam Yadav and LC Rai 15.1 Introduction 289 15.2 UVR8
Arbitrated Signalling 290 15.2.1 Constitutively Photomorphogenic 1 (COP1) 290 15.2.2 Elongated Hypocotyl 5 (HY5) and HYH 291 15.2.3 Repressor of UV
B Photomorphogenesis 1 (RUP1) and RUP2 292 15.3 Molecular Mechanism of Photoreceptor
Mediated Signalling 293 15.4 UVR8 Involvements in Different Pathways 296 15.4.1 Protection from PhotöInhibition and Photo Oxidative Stress 297 15.4.2 Flavonoid and Alkaloid Pathways 298 15.4.3 DNA Damage Repair 299 15.4.4 Defence Against Pathogens 299 15.4.5 Inhibition of Plant Shade Avoidance 300 15.4.6 Regulation of Leaf Morphogenesis 300 15.4.7 Regulation of Root Growth and Development 300 15.4.8 Circadian Clock 301 15.5 Conclusion and Future Perspectives 301 Acknowledgements 302 References 302 Index 309