Assessment of Genetic Architecture of Some Economic Traits in Okra (Abelmoschus esculentus (L.) Moench) through Generation Mean Analysis

Abstract

The nature and magnitude of gene action was analysed using six generations viz., P 1 , P 2 , F 1 , F 2 , BC 1 and BC 2 for yield and yield contributing characters in four inter varietal crosses of okra. The scaling and joint scaling tests indicated the presence of epistatic gene effect for all the characters in four crosses. Duplicate epistasis was predominant in most of the yield and yield attributing characters in all the four crosses except number of fruits per plant, which showed complimentary epistasis. Study of gene action revealed that both additive and non-additive components of genetic variations were found important for the inheritance of fruit yield and its attributes. However, fixable components of genetic variation i.e., Additive gene effects with additive x additive interactions for yield contributing traits i.e. fruit length and number of fruits per plant in all crosses except HB-25-2 x HB-32, for fruit diameter in all crosses except HB-40 x HB-27 and for fruit weight in crosses Hisar Naveen x Varsha Uphar and HB-25-2 x HB-32 were found significant. These traits in these crosses can be improved through pedigree method. The rest of the characters in respective cross combinations showed additive and non-additive type of gene effects. These traits would be possible to improve by either recurrent selection or biparental mating system in segregating generations followed by selection. Further, all the three types of gene actions viz., additive (d), dominance (h) and epistatic gene effects [additive x additive (i), additive x dominance (j) and dominance x dominance (l)] were involved in the inheritance of number of fruits per plant in the crosses HB-25-2 x HB-32 and HB-1157 x Pusa Sawani.

Generation mean analysis unveils genetic effects controlling major yield traits in okra [Abelmoschus esculentus (L.) Moench].

“…Complementary epistasis for plant height was also reported by Deshmukh et al (2021) in all six crosses they studied. Similar findings were reported by Srikanth et al (2018).…”

“…Das et al (2013) and Soher et al (2013) also observed non-additive gene action for this trait. Similar epistatic interactions were also reported by Srikanth et al (2018) and Arora et al (2007). Among epistatic interactions additive x dominance (j) and dominance x dominance (l) interactions were significant.…”

“…of gene effects for various yield traits in okra[Mather and Jinks (1982) six-parameter model] yield per plant 110.44** ± 4.75 41.69** ± 3.84 133.5** ± 20.82 84.35**± 20.50 117.3** ± 9.33 -129.5**± 25.49 Duplicate 186.61**was highly significant for seed germination percentage, inter nodal length, number of fruits per plant and was found to be significant for number of fruiting nodes, plant height, fruit length, fruit diameter and fruit weight.The scale D was highly significant for yield per plant and significant for inter-nodal length and number of primary branches. Our results were consistent with the reports ofPanda and Singh (2003), Akthar et al (2010),Mistry (2013),Wakode et al (2016),Srikanth et al (2018) andDeshmukh et al (2021). One or more of gene effects (m, d, h, i, j and l) measured in six parameter model were either significant or highly significant with positive values for all the yield traits studied (Table2).…”

“…Significant additive gene action was reported by and Wakode et al (2016). Significance of Additive genetic effect (d) and dominance x dominance (l) interaction was earlier reported by Patel et al 2013 andSrikanth et al (2018). The type of gene action is duplicate type.…”

“…On the other hand, complementary type of nonallelic interaction has been observed for days to 50 percentage flowering, inter-nodal length, plant height, fruit diameter and fruit weight. Role of complementary epistasis in genetic control of various traits in okra was earlier reported by Srikanth et al 2018 andDeshmukh et al 2021. For the improvement of these traits heterosis breeding will be most appropriate.…”