Leaf Age-Dependent Effects of Foliar-Sprayed CuZn Nanoparticles on Photosynthetic Efficiency and ROS Generation in Arabidopsis thaliana

Materials

Ioannis-DimosthenisS. Adamakis¹  Ilektra Sperdouli¹  Michael Moustakas¹  Julietta Moustaka¹  Catherine Dendrinou-Samara²  Orestis Antonoglou² 

[1] Department of Botany, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece;Laboratory of Inorganic Chemistry, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece;

关键词: bimetallic nanoparticles;    hydrogen peroxide;    mature leaves;    non-photochemical quenching;    photoprotective mechanism;    photosynthetic heterogeneity;    plastoquinone pool;    redox state;    spatiotemporal heterogeneity;    young leaves;   

DOI  :  10.3390/ma12152498

来源: DOAJ

【 摘 要 】

Young and mature leaves of Arabidopsis thaliana were exposed by foliar spray to 30 mg L⁻¹ of CuZn nanoparticles (NPs). The NPs were synthesized by a microwave-assisted polyol process and characterized by dynamic light scattering (DLS), X-ray diffraction (XRD), and transmission electron microscopy (TEM). CuZn NPs effects in Arabidopsis leaves were evaluated by chlorophyll fluorescence imaging analysis that revealed spatiotemporal heterogeneity of the quantum efficiency of PSII photochemistry (Φ_PSΙΙ) and the redox state of the plastoquinone (PQ) pool (q_p), measured 30 min, 90 min, 180 min, and 240 min after spraying. Photosystem II (PSII) function in young leaves was observed to be negatively influenced, especially 30 min after spraying, at which point increased H₂O₂ generation was correlated to the lower oxidized state of the PQ pool. Recovery of young leaves photosynthetic efficiency appeared only after 240 min of NPs spray when also the level of ROS accumulation was similar to control leaves. On the contrary, a beneficial effect on PSII function in mature leaves after 30 min of the CuZn NPs spray was observed, with increased Φ_PSΙΙ, an increased electron transport rate (ETR), decreased singlet oxygen (¹O₂) formation, and H₂O₂ production at the same level of control leaves.An explanation for this differential response is suggested.

【 授权许可】

Unknown