RESUMO
The uptake of (137)Cs and (90)Sr 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 (137)Cs and (90)Sr 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 (90)Sr activity concentration in grain and straw, and the calcium concentration. The correlation between (137)Cs and potassium was not significant. The results suggest that certain varieties of spring wheat used in normal agricultural practice accumulate less (137)Cs and (90)Sr into grain than others. Some spring wheat varieties accumulated relatively less (137)Cs, but did not accumulate less (90)Sr. One variety, Quattro, had a significantly lower uptake of both (90)Sr (for grain) and (137)Cs (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 (90)Sr and (137)Cs and allowing farmers to produce food-grade grain.
