Inheritance of Cadmium Concentration in Lettuce

Parental, F 1 , F 2 , and F 3 generations were used to determine the inheritance of Cd concentration in lettuce ( Lactuca sativa L.). Three plant introductions—PI 278080, PI 140398, and PI 169493—were parents for two crosses—PI 278080 × PI 140398 and PI 169493 × PI 278080. Data from the F 2 and F 3 generations did not fit simple Mendelian models. Broad sense heritability estimates for the two crosses, calculated from parental and F 2 variances, were 0.38 and 0.29, respectively. Narrow sense estimates, calculated by the standard-unit regression analyses of F 3 family means on F 2 parents, were 0.05 and 0.30, respectively. Low, nonsignificant correlations were obtained between Cd concentration and dry weight of tissue samples in both F 2 and F 3 generations, indicating that selection for low concentration should not affect yield.