Wide range of grain Cd was observed than of Zn
among the 110 hybrid rice cultivars grown in a neutral,
low Cd content paddy soil. Super rice cultivars exerted
significantly higher grain Cd uptake with a higher ratio
of Cd/Zn than the common hybrid rice cultivars. Thus,
the super rice cultivars may possess a greater risk than
those of hybrid ones from Cd exposure and Zn deficiency
through dietary intake for human health, especially for
subsistence diet farmers in South China where enhanced
Cd bioavailability and Zn deficiency occurs due to low pH
and poor soil nutrient status. However, a small portion of
the common rice cultivars screened here had lower grain
Cd and Cd/Zn ratio. This offers an opportunity to conduct
a low-Cd cultivar breeding and cultivation for a safe highyielding
rice production while great care is needed for
using super rice in rice production of South China with
Cd contaminated and bioavailability enhanced soils.