Effect of silicon application on cadmium uptake and distribution in strawberry plants grown on contaminated soils

Cadmium (Cd) is one of the most toxic metals affecting the environment. The initial Cd concentration in soil could influence its uptake and distribution in plants. In this paper, the effects of soil type and contamination level on Cd uptake and distribution within the 'Elsanta' strawberry plant are presented. Silicon ( Si) as potassium silicate, applied by spraying or directly onto soil, was used to decrease Cd uptake and alleviate it toxic effects. Plants were grown in a greenhouse in sandy and sandy clay-loam soils contaminated with five different Cd levels. The concentrations of Cd in roots, stems, leaves, and fruits were measured after fruit harvest. The results obtained showed that the initial soil contamination and soil type significantly influenced Cd uptake and its distribution within the strawberry plants. As expected, Cd uptake by strawberry plants increased with the initial level of this element in the soil. However, plants grown on sandy soil had a significantly higher concentration of Cd in all organs compared with plans grown on sandy clay-loam soil. Silicon used as soil amendment prior to planting was effective in preventing excessive Cd uptake by strawberry plants grown on sandy soil. The lower Cd concentration as the effect of Si application was observed in stems, leaves, and fruits but not in roots. A foliar application by spraying with potassium silicate did not reduce the concentration of Cd in the individual parts of strawberry plants.