Assessment of yield and cadmium (Cd) concentration dynamics of rice (Oryza sativa L.) in paddy soils with various levels of Cd contamination

Abstract

Cadmium (Cd) contamination in agricultural land poses a serious threat to human health due to the absorption of this toxic element by crops. This research aims to evaluate the effects of Cd at different soil contamination levels on yield and Cd concentration of rice (Oryza sativa L.). Rice was grown under controlled greenhouse conditions with seven different concentrations of Cd (0.1 [control], 1.9, 3.6, 7.2, 8.5, and 10.3 mg kg-1) to investigate changes in soil chemical properties and their effects on rice growth and yield. The total Cd content in the soil was significantly and positively correlated with organic matter (OM) and P2O5 levels. As soil Cd concentration increased, negative correlations were observed with key rice growth parameters, including the panicle number per plant, yields, and tiller number after 60 days. The total (CdTotal) and plant-available (CdMehlich3) Cd concentrations in soil were found to be 4.787 and 2.733 mg kg-1, respectively, and the Cd concentration in polished rice reached the edible limit of 0.2 mg kg-1. This study provides valuable insights into the relationship between soil Cd contamination, plant-available Cd concentration, and Cd accumulation in polished rice. By understanding these dynamics, effective standards can be established to assess and mitigate the risk of Cd contamination in agricultural environments.