Photoprotection and Other Responses of Plants to High Light Stress

PHOTO PROTECTION 604 Prevention oj Excessive Light Absorption... 604 Removal of Excess Excitation Energy Directly within the Light-Capturing System ......... ...... . . ..... ..... . .... . ..... ...... .... . .. . .. . . ..... . . . ... ... . 604 Removal oj Active Oxygen Formed in the Photochemical Apparatus ........ . . .. . . . . . . 605 INACTIV A TIONiTURNOVER OF PS II 606 THE XANTHOPHYLL CYCLE AND THERMAL ENERGY DISSIPATION: A PHOTOPROTECTIVE RESPONSE 608 Characteristics oj the Xanthophyll Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . 608 Association Among the De-epoxidized State oj the Xanthophyll Cycle, Thermal Energy Dissipation. and Photoprotection .. .. . . . .. . . ...... .. .. ... ... 609 Operation of the Xanthophyll Cycle in the Field . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . .... . . . .. . . . . 611 CONCLUSIONS 618