Genetic Parameters in Macaroni Wheat*

Some genetic parameters of breeding value were evaluated for 14 traits in macaroni wheat in each 125 F₁s and F₂s generated from 25 lines and 5 testers. Combining ability analyses revealed highly significant differences among males, females and male × female interactions for all the characters in both the generations. Estimates due to σ²g and σ²s were significant for all the traits in F_rs and F₂s. Seven characters showed high magnitude of additive gene action in F₁s while 11 characters exhibited preponderance of non-additive gene action in F₂s following greater value to σ²s. All the developmental components except early growth vigour showed partial dominance in F₁ generation and overdo-minance in F₂ generation while yield and its contributing characters reflected overdominance of consistent nature from F₁ to F₂ generations including early growth vigour, a developmental trait. Complete dominance was observed for harvest index in F, hybrids and overdominance in F₂ families. Number of spikelets per main spike indicated consistent partial dominance from F₁ to F₂ generations Consequent upon the present findings, breeding methodologies such as population improvement approach in the form of biparental or triple test cross matings coupled with recurrent selection and multiple breeding techniques were suggested for the exploitation of both additive and non-additive gene actions in durum wheat.