Abstract:
Zinc oxide nanoparticles (ZnO NPs) have emerged as a prominent tool in agriculture. Since photosynthetic function is a significant measurement of phytotoxicity and an assessment tool prior to large-scale agricultural applications, the impact of engineered irregular-shaped ZnO NPs coated with oleylamine (ZnO@OAm NPs) were tested. The ZnO@OAm NPs (crystalline size 19 nm) were solvothermally prepared in the sole presence of oleylamine (OAm) and evaluated on tomato (Lycopersicon esculentum Mill.) photosystem II (PSII) photochemistry. Foliar-sprayed 15 mg L-1 ZnO@OAm NPs on tomato leaflets increased chlorophyll content that initiated a higher amount of light energy capture, which resulted in about a 20% increased electron transport rate (ETR) and a quantum yield of PSII photochemistry (ΦPSII) at the growth light (GL, 600 μmol photons m-2 s-1). However, the ZnO@OAm NPs caused a malfunction in the oxygen-evolving complex (OEC) of PSII, which resulted in photoinhibition and increased ROS accumulation. The ROS accumulation was due to the decreased photoprotective mechanism of non-photochemical quenching (NPQ) and to the donor-side photoinhibition. Despite ROS accumulation, ZnO@OAm NPs decreased the excess excitation energy of the PSII, indicating improved PSII efficiency. Therefore, synthesized ZnO@OAm NPs can potentially be used as photosynthetic biostimulants for enhancing crop yields after being tested on other plant species.
摘要:
氧化锌纳米颗粒(ZnONP)已成为农业中的重要工具。由于光合功能是植物毒性的重要测量和大规模农业应用之前的评估工具,测试了用油胺涂覆的工程不规则形状的ZnONPs(ZnO@OAmNPs)的影响。ZnO@OAmNP(晶体尺寸19nm)是在仅存在油胺(OAm)的情况下进行溶剂热制备的,并在番茄(LycopersiconesculentumMill上进行了评估。)光系统II(PSII)光化学。在番茄小叶上叶面喷施15mgL-1ZnO@OAmNPs增加了叶绿素含量,从而引发了更高的光能捕获量,这导致在生长光(GL,600μmol光子m-2s-1)。然而,ZnO@OAmNPs在PSII的析氧络合物(OEC)中引起了故障,这导致光抑制和增加的ROS积累。ROS的积累是由于非光化学猝灭(NPQ)的光保护机制降低和供体侧光抑制所致。尽管ROS积累,ZnO@OAmNPs降低了PSII的过量激发能,表明改进的PSII效率。因此,在其他植物物种上进行测试后,合成的ZnO@OAmNPs可以潜在地用作光合生物刺激剂,以提高作物产量。