Li Xiufen, Wang Xiaoxuan, Ma Xingmao, Sun Wenjie, Chen Kun, Dou Fugen
Department of Plant and Environmental Sciences, New Mexico State University, Las Cruces, NM, United States.
Texas A&M AgriLife Research and Extension Center at Beaumont, Texas A&M University System, Beaumont, TX, United States.
Front Plant Sci. 2024 May 28;15:1338530. doi: 10.3389/fpls.2024.1338530. eCollection 2024.
Arsenic (As) pollution in rice ( L.), a staple food for over 3.5 billion people, is a global problem. Mixed effects of Zn, Cu, and Si amendments on plant growth and yield, including in the presence of As pollution have been reported in previous studies. To better investigate the effectiveness of these amendments on rice growth, yield, and As accumulation, we conducted a rice greenhouse experiment with 11 treatments, including control pots with and without As contamination and pots with amendments of ZnO, CuO, and SiO nanoparticles (ZnO NPs, CuO NPs, and SiO NPs), their ionic counterparts (ZnSO, CuSO, and NaSiO), and bulk particles (ZnO BPs, CuO BPs, and SiO BPs). Compared with the background soil, the treatment of adding As decreased rice plant height, panicle number, and grain yield by 16.5%, 50%, and 85.7%, respectively, but significantly increased the As accumulation in milled rice grains by 3.2 times. Under As contamination, the application of Zn amendments increased rice grain yield by 4.6-7.3 times; among the three Zn amendments, ZnSO performed best by fully recovering grain yield to the background level and significantly reducing grain As/total As ratio by 46.9%. Under As contamination, the application of Cu amendments increased grain yield by 3.8-5.6 times; all three Cu amendments significantly reduced grain As/total As ratio by 20.2-65.6%. The results reveal that Zn and Cu amendments could promote rice yield and prevent As accumulation in rice grains under As contamination. Despite the observed reduction in As toxicity by the tested NPs, they do not offer more advantages over their ionic counterparts and bulk particles in promoting rice growth under As contamination. Future field research using a broader range of rice varieties, investigating various As concentrations, and encompassing diverse climate conditions will be necessary to validate our findings in achieving more extensive understanding of effective management of arsenic contaminated rice field.
大米是全球超过35亿人的主食，大米中的砷污染是一个全球性问题。以往研究报道了锌、铜和硅改良剂对植物生长和产量的混合效应，包括在砷污染情况下的效应。为了更好地研究这些改良剂对水稻生长、产量和砷积累的有效性，我们进行了一项水稻温室试验，设置了11种处理，包括有无砷污染的对照盆以及添加氧化锌、氧化铜和二氧化硅纳米颗粒（ZnO NPs、CuO NPs和SiO NPs）、它们的离子对应物（ZnSO₄、CuSO₄和Na₂SiO₃）和块状颗粒（ZnO BPs、CuO BPs和SiO BPs）的盆。与背景土壤相比，添加砷的处理使水稻株高、穗数和籽粒产量分别降低了16.5%、50%和85.7%，但显著增加了精米籽粒中的砷积累3.2倍。在砷污染条件下，施用锌改良剂使水稻籽粒产量提高了4.6 - 7.3倍；在三种锌改良剂中，ZnSO₄表现最佳，能使籽粒产量完全恢复到背景水平，并显著降低籽粒砷/总砷比值46.9%。在砷污染条件下，施用铜改良剂使籽粒产量提高了3.8 - 5.6倍；所有三种铜改良剂均显著降低籽粒砷/总砷比值20.2% - 65.6%。结果表明，在砷污染条件下，锌和铜改良剂可促进水稻产量并防止砷在水稻籽粒中积累。尽管观察到测试的纳米颗粒降低了砷的毒性，但在砷污染条件下促进水稻生长方面，它们并不比其离子对应物和块状颗粒具有更多优势。未来需要进行更广泛的田间研究，使用更多品种的水稻，研究不同的砷浓度，并涵盖各种气候条件，以验证我们的研究结果，从而更全面地了解砷污染稻田的有效管理。
