Objective This study aimed to establish a rapid screening method to facilitate the selection of suitable rice varieties for cultivated soils with different cadmium (Cd) contamination levels.

Methods A hydroponic experiment with graded Cd concentrations (0, 0.01, 0.10, and 1.00 mg·L⁻¹) was conducted to investigate the absorption and translocation characteristics of Cd at the late tillering stage in 20 major rice varieties cultivated in Guangdong Province. The sensitivity of Cd accumulation of rice was systematically analyzed.

Result Two-way analysis of variance revealed significant differences in Cd accumulation capacity among cultivars under the three Cd stress (P<0.05), with a significant interaction between cultivar and Cd²⁺ concentration. These variations were primarily attributed to genotypic differences in root uptake and stem-to-leaf translocation efficiency. Based on these findings, a rapid screening system for the hydroponic tillering stage was established with the following criteria: ① Under hydroponic treatment with ρ (Cd²⁺)=0.01 mg·L⁻¹, the Cd content in the root (threshold: 45 mg·kg⁻¹) was classified into low- and high-accumulation varieties; ② When ρ (Cd²⁺) increasing from 0.01 mg·L⁻¹ to 0.10 mg·L⁻¹, the sensitivity of the rice to Cd²⁺ concentration can be determined by the increase multiple of Cd content in the root (threshold: 10-fold); ③ When ρ (Cd²⁺)=1.00 mg·L⁻¹, the transfer sensitivity of Cd can be evaluated by the stem and leaf to root translocation factor (threshold: 0.07). A preliminary screening of rice cultivars using this rapid screening method hydroponic system at the tillering stage led to the identification of four Cd-accumulation sensitivity types: low-accumulation sensitive, low-accumulation insensitive, high-accumulation sensitive, and high-accumulation insensitive.

Conclusion Four categories of rice cultivars by rapid screening method exhibiting differential Cd accumulation were identified as potential candidates for low-Cd rice cultivation. Further field validation is required to confirm the environmental stability of selected cultivars, and the evaluation system should be optimized to enhance its applicability and accuracy.