The Effect of Different Lime Forms on Cadmium Uptake of Durum Wheat Varieties

Cadmium (Cd) accumulation in durum wheat (Triticum durum L.) and its human transport with food chain is a major environmental issue worldwide. The research was based on a pot experiment conducted on fifteen durum wheat cultivars, grown on acid soil pH 5.2. The effect of application of two different lime form (lime1=CaO; Calcium oxide and lime2=CaCO3; limestone) and on shoot dry weight and shoot concentrations of cadmium (Cd). Durum wheat cultivars were grown in strongly acid soil pH 5.2 treated with control (lime0), lime1 (CaO3 g kg-1 soil), lime2 (5.36 g CaCO3) and Cd (5 and 10 mg kg-1 soil) and harvested after 62 days of growth under greenhouse conditions. Durum wheat cultivars without lime fertilization caused decrease in shoot growth, in all durum wheat cultivars and at high Cd treatment. On the other hand, application of lime to the soil resulted in an increase in dry matter yield at both Cd5 and Cd10 doses. While average shoot dry matter yield of lime0 conditions of cadmium 10 dose was 47 mg plant-1, this yield increased to 120 mg plant-1 in lime1 application and to 111 mg plant-1 in lime2 application. Shoot Cd concentrations of durum wheat varieties caused a statistically significant decrease with lime1 and lime2 applications, whereas lime0 and lime2 applications of Cd5 dose caused 46% and 30% decrease in average Cd concentrations, respectively. The results indicated that all durum wheat cultivars were more susceptible to both without lime and Cd toxicity as compared to lime treatment. Cadmium toxicity in the shoot was relieved by lime1 and lime2 treatment. The results indicate that lime protects plants from Cd toxicity in durum wheat cultivars.