Inbred line development through B × B crosses for combining ability and gene action in sunflower (Helianthus annuus L.)

To estimate general combining ability and specific combing ability effects for various characters eight inbred lines were crossed in 8×8 full diallel fashion. The 56 F₁ crosses along with parents and checks were planted in simple lattice design with two replication at Main Agricultural Research Station, Raichur during rabi 2015–16. The results exhibited that SCA variances were higher than GCA variances for all traits studied which indicated the presence of non-additive gene action. Three inbreds 39 B, 852 B and 400 B were found to be the best general combiners for majority of the traits. Three crosses 104 B×39 B, 400 B×234 B and 17 B×400 B were found to be the best specific combiners for majority of the characters studied viz., days to 50% flowering, days to maturity, head diameter, stem girth, volume weight, oil content and seed yield per plant. These specific crosses could be further utilized for deriving desirable inbreds from advanced generations.