Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education)/Carbon Neutrality Interdisciplinary Science Centre, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China.
Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003.
Proc Natl Acad Sci U S A. 2024 Nov 12;121(46):e2414822121. doi: 10.1073/pnas.2414822121. Epub 2024 Nov 4.
To address rising global food demand, the development of sustainable technologies to increase productivity is urgently needed. This study revealed that foliar application of zinc oxide nanoparticles (ZnO NPs; 30 to 80 nm, 0.67 mg/d per plant, 6 d) to rice leaves under heatwave (HW) stress increased the grain yield and nutritional quality. Compared with the HW control, the HWs+ZnO group presented increases in the grain yield, grain protein content, and amino acid content of 22.1%, 11.8%, and 77.5%, respectively. Nanoscale ZnO aggregated on the leaf surface and interacted with leaf surface molecules. Compared with that at ambient temperature, HW treatment increased the dissolution of ZnO NPs on the leaf surface by 25.9% and facilitated their translocation to mesophyll cells. The Zn in the leaves existed as both ionic Zn and particulate ZnO. Compared with the HW control, foliar application of ZnO NPs under HW conditions increased leaf nutrient levels (Zn, Mn, Cu, Fe, and Mg) by 15.8 to 416.9%, the chlorophyll content by 22.2 to 24.8%, Rubisco enzyme activity by 21.2%, and antioxidant activity by 26.7 to 31.2%. Transcriptomic analyses revealed that ZnO NPs reversed HW-induced transcriptomic dysregulation, thereby enhancing leaf photosynthesis by 74.4%. Additionally, ZnO NPs increased the diversity, stability, and enrichment of beneficial microbial taxa and protected the phyllosphere microbial community from HW damage. This work elucidates how NPs interact with the phyllosphere, highlighting the potential of NPs to promote sustainable agriculture, especially under extreme climate events (e.g., HWs).
为了应对全球粮食需求的增长，迫切需要开发可持续的技术来提高生产力。本研究表明，在热浪（HW）胁迫下，向水稻叶片喷施氧化锌纳米粒子（ZnO NPs；30 至 80nm，0.67mg/d 每株，6d）可提高粮食产量和营养品质。与 HW 对照相比，HWs+ZnO 组的产量、籽粒蛋白质含量和氨基酸含量分别增加了 22.1%、11.8%和 77.5%。纳米级 ZnO 在叶片表面聚集并与叶片表面分子相互作用。与常温相比，HW 处理使叶片表面 ZnO NPs 的溶解增加了 25.9%，并促进了它们向叶肉细胞的转运。叶片中的 Zn 以离子态 Zn 和颗粒态 ZnO 的形式存在。与 HW 对照相比，在 HW 条件下叶面喷施 ZnO NPs 使叶片养分水平（Zn、Mn、Cu、Fe 和 Mg）增加了 15.8 至 416.9%，叶绿素含量增加了 22.2 至 24.8%，Rubisco 酶活性增加了 21.2%，抗氧化活性增加了 26.7 至 31.2%。转录组分析表明，ZnO NPs 逆转了 HW 引起的转录组失调，从而使叶片光合作用增强了 74.4%。此外，ZnO NPs 增加了有益微生物类群的多样性、稳定性和富集度，并保护了叶际微生物群落免受 HW 破坏。这项工作阐明了 NPs 如何与叶际相互作用，突出了 NPs 促进可持续农业的潜力，特别是在极端气候事件（如 HWs）下。
