Studies on combining ability and heterosis in three-way hybrids in forage pearl millet

Abstract

In the present study, two A₅ CMS lines, ICMA 03333 and ICMA 01777 were crossed with 15 different 5 viz. maintainers having high biomass during kharif 2016. The thirty male sterile F₁ s were crossed with two high 1 biomass pollinators, viz. Giant Bajra and RBC-2 during Kharif 2017 to generate three-way hybrids. A total of sixty, three-way hybrids were evaluated in summer (Environment I) and kharif (Environment II) for agronomic traits, viz. plant height (cm), green fodder yield (kg/plot) and dry fodder yield (kg/plot) and quality traits, viz. dry matter (%), In vitro dry matter digestibility (%) and crude protein (%) during kharif 2018. Significant variability was present in parents and hybrids for a majority of the traits under both environments. The pooled analysis of variance over environments revealed that combining ability varies with the change in environments. The lines ICMA 01777 × PB 111B and the tester Giant Bajra were identified as good general combiners for green fodder yield and its component characters as well as for quality traits, under both environments. The three-way hybrids, viz. (ICMA01777 × PB220B) × GB, (ICMA01777 × ICMB97111) × GB, (ICMA01777 × PB111B) × GB, and (ICMA01777 × ICMB00444) × GB were found to be promising cross combinations for almost all the traits under study. The high SCA cross combinations also showed high heterotic effects. Additive gene action was predominant in the inheritance of yield traits, whereas for fodder quality traits non-additive gene action was predominant.