School of Water and Environment, Chang'an University, Xi'an, China.
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China.
J Sci Food Agric. 2024 Nov;104(14):8480-8491. doi: 10.1002/jsfa.13675. Epub 2024 Jun 21.
Nanotechnology has been widely applied in agricultural science. During the process of reducing metal toxicity and accumulation in rice, nanomaterials exhibit size effects. However, there is limited knowledge regarding these size effects. We aim to explore the impact of fertilizer with various sizes of ZnO nanoparticles (ZnO-NPs) on rice growth and cadmium (Cd) accumulation and to elucidate the potential mechanism of Cd reduction in rice. Foliar applications of different concentrations (0.5 and 2 mmol L) and different sizes (30 and 300 nm ZnO-NPs) of zinc (Zn) fertilizer (Zn(NO)) were performed to investigate the effects on rice growth, Cd accumulation and subcellular distribution, and the expression of Zn-Cd transport genes.
The results suggested that all the foliar sprayings can significantly reduce the Cd concentrations in rice grains by 41-61% with the highest reduction in the application of ZnO-NPs with large size and low concentration. This is related to the enhancement of Cd fixation in leaf cell walls and downregulation of Cd transport genes (OsZIP7, OsHMA2, OsHMA3) in stem nodes. Foliar ZnO-NPs applications can increase the Zn concentration in grains by 9-21%. Foliar applications of Zn(NO) and small-sized ZnO-NPs promoted plant growth and rice yield, while the application of large-sized ZnO-NPs significantly reduced rice growth and yield.
The study suggests that the rice yield and Cd reduction are dependent on the size and concentration of foliar spraying and the use of large-sized ZnO-NPs is the most effective strategy when considering both yield and Cd reduction comprehensively. © 2024 Society of Chemical Industry.
纳米技术已广泛应用于农业科学。在降低水稻中金属毒性和积累的过程中，纳米材料表现出尺寸效应。然而，关于这些尺寸效应的知识有限。我们旨在探索不同粒径的氧化锌纳米粒子（ZnO-NPs）肥料对水稻生长和镉（Cd）积累的影响，并阐明水稻中 Cd 还原的潜在机制。叶面喷施不同浓度（0.5 和 2 mmol·L）和不同粒径（30 和 300 nm ZnO-NPs）的锌（Zn）肥（Zn（NO）），以研究其对水稻生长、Cd 积累和亚细胞分布以及 Zn-Cd 转运基因表达的影响。
结果表明，所有叶面喷施均可显著降低稻米中 Cd 浓度 41%-61%，其中大粒径、低浓度 ZnO-NPs 的喷施效果最高。这与叶片细胞壁中 Cd 固定的增强以及茎节点中 Cd 转运基因（OsZIP7、OsHMA2、OsHMA3）的下调有关。叶面喷施 ZnO-NPs 可使稻米中 Zn 浓度增加 9%-21%。叶面喷施 Zn（NO）和小粒径 ZnO-NPs 可促进植物生长和水稻产量，而大粒径 ZnO-NPs 的应用则显著降低了水稻的生长和产量。
研究表明，水稻产量和 Cd 减少取决于叶面喷施的粒径和浓度，综合考虑产量和 Cd 减少，使用大粒径 ZnO-NPs 是最有效的策略。© 2024 化学工业协会。
