Gene action and combining ability analysis for flower yield and its component traits in interspecific hybrids of marigold (Tagetes spp)

Abstract

A line × tester set of 14 parents involving three male sterile lines of Tagetes erecta (African marigold) and 11 inbred lines of Tagetes patula (French marigold) and their 33 hybrids were analyzed to understand the nature and magnitude of gene action and to identify the best combiner and cross combinations for flower yield and its component traits. The general combining ability (GCA) and specific combining ability (SCA) components showed the predominance of additive gene action in governing number of flowers/plant and duration of flowering and non additive gene action for days to first flowering, plant height, plant spread, flower weight, flower diameter, stalk length, harvest index and flower yield/plant. Estimates of GCA effects showed that the female parent MS-8 and pollen parents Fr. Sel.1, Fr. Sel.2 and Fr.Sel.10 were the best general combiners. Thus, these parents should involve in interspecific hybridization programme for making flower yield breakthrough in marigold by producing triploids which are having longer flowering duration. The crosses MS 8 × Fr. Sel.1, MS 8 × Fr. Sel. 2 and MS 7 × Fr. Sel. 1 recorded significant desirable SCA effects for maximum number of traits, viz. days to first flowering, plant height, plant spread, number of flowers/plant, flower weight, flower diameter, duration of flowering and flower yield/plant except stalk length and harvest index.