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With mankind entering the smart age, Cd contamination risk control in food crop revolution has been put on the agenda. Based on the theoretical basis, technical methods and developing trends, this review look back and forward the age of Cd contamination risk control driven by 'genotype (G)+ envirotype (E)' dual-engines. Focusing on G, an inter-specific Cd contamination risk assessment meta-analysis was carried, in which a higher Cd contamination risk in rice and wheat than maize was observed. So different strategies are recommended to be taken considering inter-specific difference. To control the risk in crops with high accumulating characteristic, smart creation of low-Cd crops can be applied by two methods: 1) Excavating and pyramiding natural variations in natural population and 2) designing and implementing artificial variations which do not exist in natural population. Focusing on E, the influence of environmental factors to food crop Cd accumulation was discussed and the strategy using Envirotype-to-phenotype (E2P) models to predict and implement safety threshold were offered. In the foreseeable future, with the support of environmental science, biology, big data, artificial intelligence and other interdisciplinary and multi-technology, Cd contamination risk control will move toward intelligent, efficient and directional, ultimately realizing the revolutionary transformation from 'experience' to 'smart'. [ABSTRACT FROM AUTHOR]

A three-crop repeated phytoextraction experiment was conducted using four soils (S1-S4) highly polluted with cadmium (Cd) and two enhanced phytoextraction pot experiments using the most polluted soil (S4) to investigate the feasibility of Cd removal from highly polluted soils using the Cd/zinc (Zn)-hyperaccumulator Sedum plumbizincicola. Shoot biomass showed no significant difference during the repeated phytoextraction experiment on the four test soils and shoot Cd content showed a decreasing trend with the three consecutive crops in soils S1, S2, and S3 but not in soil S4. The Cd removal rates in soils S1, S2, S3, and S4 were 84.5, 81.6, 45.3, and 32.4%, respectively. Rice straw application increased Cd extraction efficiency by 42.6% but the addition of ethylenediaminedisuccinic acid, biochar or nitrogen had no effect on Cd remediation. Shoot Cd content increased significantly (1.57 and 1.71 times, respectively) at low (S0-1) and high (S0-2) sulfur addition rates. Soil extractable-Cd in S0-1 after the experiment showed no significant difference from the control but was 2.43 times higher in S0-2 than in the control. These results indicate that S. plumbizincicola shows good prospects for the phytoextraction of Cd from highly polluted soils and that the process can be enhanced by adding straw and/or sulfur to the soil. [ABSTRACT FROM AUTHOR]