腐植酸负载纳米零价铁对镉污染农田水稻籽粒代谢的影响OA北大核心CSTPCD

In our study,a humic acid(HA)supported nanoscal zero valent iron(nZVI)material(nZVI@HA)was prepared by adsorption complexation-liquid phase reduction method to reveal the mechanism of the nutrients synthetic process in rice grains during the cadmium(Cd)remediation process.The effects of single nZVI@HA,nZVI,HA,and the mixture of nZVI and HA on rice yield,Cd content in grains,and metabolite compositions of grains in the soil Cd remediation process,were studied.Here,we conducted a series of rice pot experiments equipped with ultra-high-performance liquid chromatography-mass spectrometry technology and inductively coupled plasma mass spectrometry.The results demonstrated that the three Fe0 treatments could increase rice yield and reduce the Cd content in rice grains.Especially under the application of nZVI@HA,the rice yield was significantly increased to 188%of control,and the Cd content in grains was reduced to 0.155 mg·kg-1 lower than the national Cd limit standard for rice(0.2 mg·kg-1,GB 2762-2022).Metabolomics analysis showed that the three Fe0-containing treatments could significantly promote betalain biosynthesis and the arginine and proline metabolism in grains(P<0.05 and VIP>1).Notably,the grains could also respond highly and specifically to nZVI@HA through alanine,aspartate,and glutamate metabolism,nucleotide metabolism,glycine,serine and threonine metabolism,and glycerophospholipid metabolism.Above all,nZVI@HA has specific effects on grain metabolisms,leading to improvements in rice resistance and yield.