Six generations (P1, P2, F1, F2, BC1 and BC2) of four crosses of durum wheat were used for the
estimation of genetic parameters viz., photosynthetic capacity, flag leaf area, length of peduncle,
peduncle area, and grain yield per plant. Both additive and dominance gene actions were involved
in the inheritance of all the characters except peduncle area, where only additive gene action was
important. Additive x dominance (j) interaction was important for the expression of all the traits
under study. In view of importance of both additive and non additive gene effects, a biparental
mating or diallel selective mating may be useful in isolating desirable types for genetic improvement
of the physiological traits and grain yield in durum wheat.