Analysis of Per Se and Genetic Diversity of Maize Synthetic Populations for Grain Quality: Implications for Breeding

The objective of this research was to determine wh ether phenotypic and genetic diversity could be identified for maize grain quali ty traits (percentage of starch, protein, oil, fibe r and ash) and agronomic traits. 59 maize synthetic popul ations which differed in earliness and for geographic origins were evaluated in the field at t he Agricultural Research Station Turda - Romania, for their per se value. Each synthetic population was tested only o ne year and was characterized for their ear characteristics and grain quality attribu tes. The grain oil and ash content showed high variability among genotypes. The experiment was conducted over 2 years (2006-2007) and 2 locations (Turda and Targu- Mures). Analysis of variance showed significant dif ferences among the genotypes for all traits studied . General combining ability (GCA) effects were more important for grain content than specific combining ability (SCA). The occurrence of low inte ractions between synthetic populations and testers for all characters suggested the occurrence of high statistical additive effects expressed whatever the system of population evaluation. These results support breeding effort towards the genetic improvement of grain quality traits in "Tur da" maize germplasm.