期刊
ACTA OECOLOGICA-INTERNATIONAL JOURNAL OF ECOLOGY
卷 73, 期 -, 页码 53-60出版社
ELSEVIER SCIENCE BV
DOI: 10.1016/j.actao.2016.03.001
关键词
Non-photochemical quenching; Cyclic electron flow; Osmotic potential at turgor loss point; Predawn leaf water potential; Seasonal drought
类别
资金
- National Natural Science Foundation of China [31570406, 31470470]
- Natural Science of China [U1202234]
- Natural Science of the Yunnan Province [U1202234]
Hemiepiphytic Ficus species exhibit more conservative water use strategy and are more drought-tolerant compared with their non-hemiepiphytic congeners, but a difference in the response of photosystem I (PSI) and photosystem II (PSII) to drought stress has not been documented to date. The enhancement of non-photochemical quenching (NPQ) and cyclic electron flow (CEF) have been identified as important mechanisms that protect the photosystems under drought conditions. Using the hemiepiphytic Ficus tinctoria and the non-hemiepiphytic Ficus racemosa, we studied the water status and the electron fluxes through PSI and PSII under seasonal water stress. Our results clearly indicated that the decline in the leaf predawn water potential (psi(pd)), the maximum photosynthetic rate (A(max)) and the predawn maximum quantum yield of PSII (F-v/F-m) were more pronounced in F. racemosa than in F. tinctoria at peak drought. The F-v/F-m of F. racemosa was reduced to 0.69, indicating net photoinhibition of PSII. Concomitantly, the maximal photo-oxidizable P700 (P-m) decreased significantly in F. racemosa but remained stable in F. tinctoria. The fraction of non-photochemical quenching [Y(NPQ)] and the ratio of effective quantum yield of PSI to PSII [Y(I)/Y(II)] increased for both Ficus species at peak drought, with a stronger increase in F. racemosa. These results indicated that the enhancement of NPQ and the activation of CEF contributed to the photoprotection of PSI and PSII for both Ficus species under seasonal drought, particularly for F. racemosa. (C) 2016 Elsevier Masson SAS. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据