Effect of soil contamination with cadmium and application of neutralizing substances on the yield of oat (Avena sativa L.) and on the uptake of cadmium by this crop

Abstract

Cadmium emitted to the natural environment due to anthropogenic pressure can easily move through the trophic chain, thus posing a threat to human and animal health. Soil contamination with cadmium can cause disorders in the growth and development of plants, and therefore may have an adverse effect on the volume and quality of yields. The purpose of this study has been to evaluate the effect of soil contamination with incremental doses of cadmium together with the application of neutralizing substances on the yield of oat (Avena sativa L.) and on the content, uptake and distribution of cadmium in oat plants. The research was based on a pot experiment conducted on cv. Dragon oat, grown on soil with the grain-size composition of loamy sand. Cadmium was introduced to soil in the form of cadmium chloride, in doses equal 0, 10, 20, 30 and 40 mg Cd kg-1. In order to alleviate the negative effect of soil contamination with cadmium, neutralizing substances were used, such as compost, lime and brown coal. The statistical analysis of the results demonstrated the presence of a negative correlation between the cadmium doses and the volume of oat yields. The lowest cadmium dose (10 mg Cd kg-1 of soil) significantly decreased the yield of oat straw and roots; regarding the grain yield, it was significantly depressed by the two highest cadmium doses (30 and 40 mg Cd kg-1 of soil). Of the three neutralizing substances applied, compost had a positive effect on the quantity of grain yield, compost and brown coal affected positively the yield of straw, while soil liming significantly decreased the yield of roots. Soil contamination with cadmium significantly affected the content of cadmium, raising it in the separated parts of oat plants, of which roots contained the distinctly highest amounts of the pollutant. The highest cadmium uptake (1.50 mg Cd pot-1) was detected in oat straw, which on average accumulated 58% of this xenobiotic. All the applied substances neutralizing the soil contamination with cadmium significantly decreased the content and the uptake of this element by oat grain, straw and roots, with lime producing the strongest impact.