Moderate photoinhibition of PSII and oxidation of P700 contribute to chilling tolerance of tropical tree species in subtropics of China

Abstract

electron flow through PSI; ETR(II) -photosynthetic electron flow through PSII; Fd -ferredoxin; Fv/Fm -maximum quantum yield of PSII in the dark-adapted state; gs -stomatal conductance; LEF -linear electron flow; NPQ -nonphotochemical quenching; P680 -chlorophyll a of PSII reaction centers; P680 + -oxidized P680; P680* -excited P680; P700 -chlorophyll a of PSI reaction centers; P700 + -oxidized P700; P700* -excited P700; PC -plastocyanin; Pm -maximum photooxidizable P700; PN -net photosynthetic rate; PQ -plastoquinone; RISE -reduction-induced suppression of electron flow; Y(I) -effective photochemical quantum yield of PSI; Y(II) -effective photochemical quantum yield of PSII; Y(CEF) -effective quantum yield of CEF; Y(NA) -acceptor-side limitation of PSI; Y(ND) -donor-side limitation of PSI; Y(NO) -yield of regulated heat dissipation of PSII; Y(NPQ) -effective quantum yield of NPQ or regulated nonphotochemical quenching; ΔpH -proton gradient. Acknowledgments: We thank Hans Lambers of the University of Western Australia, Australia for critical comments, corrections, and editing and Junjie Zhu of Guangxi University, China for the technical advice on Dual PAM-100 operations.

Response of winter wheat genotypes to salinity stress under controlled environments

“…It has been reported that proline plays a protective role in plants exposed to diverse stresses and is thought to be acting as a cellular osmotic regulator. And along with other enzymatic and non-enzymatic ROS quenching mechanisms proline regulates increased ROS production due to the reduced light-dependent and CO 2 assimilation reactions of photosynthesis ( Munns and Tester, 2008 ; Aycan et al., 2022 ; Singh et al., 2022 ; Sunoj et al., 2022 ). A study reported the genotypic differences in proline accumulation under salinity were seen in wheat genotypes ( Tavakoli et al., 2016 ).…”

Editorial

“…The research by Sunoj et al (2023) reports the effects of chilling on photosynthesis in six tropical tree species growing in the subtropics in China. The authors found that chilling induced stomatal and nonstomatal effects and photoinhibition of PSII, with severe effects in Ixora chinensis.…”