Genotypic variation in the tolerance to moderate cadmium toxicity among 20 maize genotypes with contrasting root systems

作者：Yujie Wu, Tingting An, Yamin Gao, Qiqiang Kuang, Shuo Liu, Liyan Liang, Bingcheng Xu, Suiqi Zhang, Xiping Deng, Yinglong Chen · 发表于：Journal of the Science of Food and Agriculture · 年份：2022 · DOI：10.1002/jsfa.12303 · 被引用次数：15 · 研究领域：Plant Stress Responses and Tolerance、Plant nutrient uptake and metabolism、Plant responses to water stress

Abstract BACKGROUND Cadmium (Cd) contamination in farmland is a serious environmental and safety issue affecting plant growth, crop productivity, and human health. This study aimed to investigate genotypic variation in root morphology and Cd accumulations under moderate Cd stress among diverse maize genotypes. Twenty maize genotypes with contrasting root systems were assessed for Cd tolerance 39 days after transplanting (V6, six‐leaf stage) under 20 μmol L −1 CdCl 2 using a semi‐hydroponic phenotyping platform in a glasshouse. RESULTS Cadmium stress significantly inhibited plant growth across all genotypes. Genotypic variation in response to Cd toxicity was apparent: shoot dry weight varied from 0.13 (genotype NS2020) to 0.35 g plant −1 (Dongke301) with deductions up to 63% compared with non‐Cd treatment (CK). Root dry weight of 20 genotypes ranged from 0.06 (NS2020) to 0.18 g plant −1 (Dongke301) with a deduction up to 56%. Root length ranged from 2.21 (NS590b) to 9.22 m (Dongke301) with a maximal decline of 76%. Cadmium‐treated genotypes generally had thicker roots and average diameter increased by 34% compared with CK. Genotypes had up to 3.25 and 3.50 times differences in shoot and root Cd concentrations, respectively. Principal component and cluster analyses assigned the 20 genotypes into Cd‐tolerant (five genotypes) and Cd‐sensitive (15 genotypes) groups. CONCLUSIONS Maize genotypes varied significantly in response to moderate Cd stress. Cadmium‐tolerant genotypes optim...