This experiment was carried out to investigate the degrees and directions of dominance, and gene distributions by analysing diallel crosses of oriental varieties. The analysis of Wr-Vr indicated non-allelic gene interaction for days to (lowering and number of leaves. Five Plant characteristics showed different degrees of dominance : incomplete dominance for Plant height and leaf shape, over dominance for , wield and sugar, and complete dominance for nicotine. It was shown that additive genetic variance was predominant for plant height, leaf shape, and total sugar. More number of dominant genes were present in Kavala and canthi for Plant height; Basma, Samsun and Izmir for leaf shape ; and Basma and Samsun (or nicotine. Their directions of dominance were tall height, narrow leaves, and low nicotine, respectively.