Comparative Genetic Analysis for Yield and Quality Traits in Flue Cured Tobacco

Precise knowledge regarding genetic architecture of production traits is important to devise effective breeding and selection strategies. This investigation was carried out to elucidate relationship between Hayman and Griffing analyses in flue cured Virginia (FCV) tobacco. Plant material comprised of seven tobacco cultivars which were hybridized in full diallel mating system at the Tobacco Research Sub-station, Mansehra, Pakistan during 2007. Thereon, seven parents and their forty-two F1 hybrids were sown during 2008 and 2009 at the Tobacco Research Station, Mardan (plain) and the Tobacco Research Sub-station, Mansehra (hilly). Locations in each year were considered as independent environments: Mardan 2008 as environment-1; Mansehra 2008 as environment-2; Mardan 2009 as environment-3 and Mansehra 2009 as environment-4. Field trials were conducted using randomized complete block design in four replicates. Data for all traits were subjected to Griffing and Hayman analyses of variance to get critical comparison of the results obtained through both models. Griffing analysis revealed additive type of gene action in the expression of all traits across all environments, except nicotine content. Contrarily, Hayman analysis identified both (additive and dominance) type of gene actions for yield and other traits. Similarly, Hayman analysis discriminated gene actions for various traits more specifically across environments. Based on this study, Griffing analysis was revealed to be more accommodative, whereas Hayman analysis was more stringent in specifying gene actions for various traits.