TITLE:
Photoinhibition of Leaves with Different Photosynthetic Carbon Assimilation Characteristics in Maize (Zea mays)
AUTHORS:
Yanye Ruan, Xiaoyang Li, Yanpeng Wang, Siqi Jiang, Bo Song, Zhiyou Guo, Ao Zhang, Qi Qi, Lijun Zhang, Jinjuan Fan, Yixin Guan, Zhenhai Cui, Yanshu Zhu
KEYWORDS:
Fluorescence Transient, Photosystem II (PSII), Photoprotection, Light Stress, C4 Photosynthesis
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.8 No.3,
February
4,
2017
ABSTRACT: Strong light decreases the rate of photosynthesis
and assimilates production of crop plants. Plants with different carbon
reduction cycles respond differently to strong light stress. However, variation
in photoinhibition in leaves with different photosynthetic characteristics in
maize is not clear. In this experiment, we used the first leaves (with an
incomplete C4 cycle) and fifth leaves (with a complete C4 cycle) of maize plants as well as the fifth leaves (C3 cycle) of
tobacco plants as a reference to measure the photosynthetic rate (PN)
and chlorophyll a parameters under strong light stress. During treatment, PN,
the maximal fluorescence (Fm), the maximal quantum yield of PSII
photochemistry (Fv/Fm), and the number of active
photosystem II (PSII) reaction centers per excited cross-section (RC/CSm)
declined dramatically in all three types of leaves but to different degrees. PN,
Fm, Fv/Fm, and RC/CSm were less
inhibited by strong light in C4 leaves. The results showed that
maize C4 leaves with higher rates of photosynthesis are more
tolerant to strong light stress than incomplete C4 leaves, and the
carbon reduction cycle is more important to photoprotection in C4 leaves, while state transition is critical in incomplete C4 leaves.