Inheritance of pigmentation patterns in Talinum triangulare (Jacq.) Willd.

Abstract

This study investigated the mode of inheritance of pigmentation in the floral and vegetative parts of two variants of Talinum triangulare with pink and white petals. Intraspecific hybridization involving these two variants, and their reciprocal crosses were carried out. Also backcrosses of the F1 hybrid with white petal parent were made. The various F1 hybrids were advanced to F2 and F3 generations. The F1 plants from each reciprocal cross produced light pink petal and filament colours. In the F2 a nd F3 generations, petal and filament colours segregated into ratio of 1 deep pink: 2 light pink: 1 white. Stigma colour segregated into ratio of 3 deep pink: 1 light pink. The backcross segregated into ratio of 1 light pink: 1 white for petal and filament colours; and a ratio 1 deep pink: 1light pink for stigma colour. The segregation patterns for petal and filament colour in all the generations indicate incomplete dominance of deep pink colour over white colour showing that the same gene conditions their inheritance in a monohybrid form and this gene exhibits a pleiotropic effect on the filament colour. The segregation pattern for stigma colour indicates complete dominance of deep pink over light pink colour. The same gene which is in the homozygous state conditions deep pink pigmentations on the leaf base and panicle junction in the two variants of T. triangulare investigated.

Keywords: Intraspecific, Petal Colour, Inheritance, Incomplete Dominance, Monohybrid