Biometrical Studies of Sunflower (Helianthus annuus L.)

A field research was conducted under field situation at the Research Area, University of Agriculture, Faisalabad, to study the combining ability effects for yield and its components in sunflower. Fifteen accessions of sunflower were crossed in line × tester fashion. Crosses along with their parents were grown in the field. For this purpose 10 lines (G-16, G-68, G-146, G-55, G-82, G-40, G-9, HBR-5, A-18 and G-57) and 5 testers (G-3, G-32, G-61, G-50, and G-54) were crossed according to line × tester fashion. Among the lines G-82, G-40, G-9 and HBR-5 showed positive and significant GCA effects for No. of achene per head, 100 achene weight, and achene yield per plant and proved to be good general combiners for most of these characters. Among the testers G-3, G-61 and G-54 proved as good general combiners for most of the characters i.e. for number of days to flowering, plant height, internodal length, No. of achene per head and achene yield/ plant. The hybrids G-146 × G-54, G-16 × G-61, and G-82 × G-3 showed good specific combining effects are for all the characters. Genotypic differences were significant for all the characters.