INHERITANCE OF CADMIUM CONCENTRATION IN 5 DURUM-WHEAT CROSSES

High cadmium concentration in cereal grains has been cited as a human health concern. Several reports showed that gain cadmium concentration was higher in durum (Triticum turgidum L. var. durum) than in common wheat (T. aestivum L.). The objective of this research was to determin e the inheritance of observed differences in grain cadmium concentrati on of durum wheat. This information could be used to facilitate breedi ng of cultivars with low grain cadmium concentration. Grain cadmium co ncentration was determined in the F-2 and in F-2:3 families of one cro ss and in F-2:3 and F-3:4 families of two crosses. Grain and leaf cadm ium concentration was measured in random F-8:9 and Fs:,, families of t hree crosses. All trials were conducted in the field on Aridic Haplobo rall, Vertic Cryoborall, or Gleyed Black soils. Grain cadmium concentr ation was largely controlled by a single gene, with low cadmium domina nt. Leaf cadmium concentration was highly correlated,vith grain cadmiu m concentration (r = 0.87-0.89, P < 0.01). Therefore, leaf cadmium con centration can predict the plant phenotype, which would be useful in b ackcrossing the low cadmium trait into high cadmium cultivars. Heritab ility in standard units, estimated by F-2:3 progeny regression on F-2 parent or F-2:4 progeny regression on F-2:3 parent, ranged from 0.84 /- 0.06 to 0.88 +/- 0.08, indicating that breeding of low grain cadmiu m cultivars is feasible. Heritability estimated from variance componen ts (years, locations, replications, and genotypes) was 0.78, with 90% confidence limits of 0.88 and 0.67. The simple inheritance and high he ritability of grain cadmium concentration will facilitate the breeding of low cadmium concentration durum cultivars.