Photoprotection of abscisic acid against the photoinhibition in rice seedling leaves

Photoinhibition was studied in leaves of abscisic acid(ABA)-treated rice seedlings. ABA inhibited the photosynthetic process by lower PSII photochemistry efficiency(Fv/Fm)and coefficient for non-photochemical quenching(qN). After photoinhibition under light intensity of 2 000 μmolm -2s -1 for 1 h,the extent of photoinhibition was smaller in ABA-treated rice leaves than in the control. It is suggested that ABA had a protective effect on the high light induced photoinhibition. And the results also indicated photoprotection capacity of the rice seedlings against high light photoinhibition was closely associated with xanthophyll cycle.