Using capillary electrophoresis to measure Cu/Zn superoxide dismutase concentration in leaves of wheat genotypes differing in tolerance to zinc deficiency

Three genotypes of Triticum aestieum L. and one genotype of Triticum turgidum conv. durum differing in tolerance to Zn deficiency were grown in chelate-buffered nutrient solution with or without Zn supply for up to 22 days. Genotypes that were classified as sensitive to Zn deficiency developed visual symptoms of Zn deficiency on on leaves and had the shoot/root ratio reduced, while those classified as tolerant to Zn deficiency showed neither visual symptoms nor decline in the shoot/root ratio when grown without Zn. In an early stage of Zn deficiency. concentration of the Cu,Zn superoxide dismutase (SOD) protein in leaf tissues measured by capillary electrophoresis was related positively to the tolerance of genotypes to Zn deficiency. In comparison with Zn sufficiency, exposure to Zn deficiency for 13 days caused an increase in Cu-ZnSOD concentration in tolerant genotypes, but not in sensitive ones. These results indicate that Cu/ZnSOD might be involved in reducing Zn-deficiency-related oxidative damage in genotypes tolerant re, Zn deficiency. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.