Comparison of the accumulation of 137Cs and 90Sr by six spring wheat varieties

The uptake of 137Cs and 90Sr by six varieties of spring wheat (Triticum aestivum) was compared in field trials on land contaminated by the Chernobyl accident. All the experimental varieties are officially adopted for agricultural use in Belarus and are used in large-scale production. Under identical conditions of nutrition, the productivity of the varieties varied significantly by a factor of 1.3. The extent of 137Cs and 90Sr accumulation by wheat grain, quantified as the concentration ratio, differed between the varieties by as much as a factor of 1.6, for both radionuclides. There was a significant linear positive correlation between the 90Sr activity concentration in grain and straw, and the calcium concentration. The correlation between 137Cs and potassium was not significant. The results suggest that certain varieties of spring wheat used in normal agricultural practice accumulate less 137Cs and 90Sr into grain than others. Some spring wheat varieties accumulated relatively less 137Cs, but did not accumulate less 90Sr. One variety, Quattro, had a significantly lower uptake of both 90Sr (for grain) and 137Cs (for both grain and straw) than that of the other varieties tested. The reduction efficiency achieved by the use of these varieties, however, is not as high as that achieved by soil amelioration techniques in the past. Nevertheless, since there are no additional costs or production losses associated with these varieties, their use in the contaminated areas is worth considering as a simple, practical, and effective contribution to reducing the uptake of both 90Sr and 137Cs and allowing farmers to produce food-grade grain.