| 要旨トップ | 目次 | | 日本生態学会第70回全国大会 (2023年3月、仙台) 講演要旨 ESJ70 Abstract |
一般講演(口頭発表) A02-03 (Oral presentation)
Light is essential for plant photosynthesis, but when light irradiating leaves is too strong, it causes damage, especially in photosystem II (PSII), leading to reduced photosynthetic activity (photoinhibition). It is known that plants have effective mechanisms to repair the photo-damaged PSII under excessive light energy, and photoinhibition occurs when the rate of photo-damage exceeds that of repair. These two processes can be analyzed separately by infiltration of lincomycin into intact leaves, which inhibits protein synthesis in chloroplasts and hence the PSII repair. Rates of photo-damage and repair studies are limited in woody plants. In this study, we have investigated the mechanism of photoinhibition using 18 woody species growing under different environments. Their leaves were exposed to strong light, changes of the PSII quantum yields were monitored by measuring chlorophyll fluorescence in the presence and absence of lincomycin, and the rate constant for photo-damage (inactivation) (kpi) and that of the repair (krec) were calculated. The results suggest that the 18 woody plant species have different properties in the balance between kpi and krec, indicating the different strategies to cope with excess light energy. We discuss the physiological and ecological aspects, in relation to woody plant’s habitat and leaf morphological characteristics.