Use of heterosis and transgression events to optimize sizes of leaves in variety group Burley tobacco

The manifestations of heterosis and transgression regarding the length and width of the leaves in ten hybrid combinations of Burley tobacco аre investigated. The results of the study show that in almost all variants and in both indicators, the values of the hypothetical heterosis exceed those of the real one. According to length of leaves heterosis with economic significance is observed only in one of the investigated hybrid combinations. Transgressive manifestations for this indicator are even less pronounced and are not significant in any of the studied options. In contrast to length of leaves the manifestations of heterosis are of economic importance in six of the ten crosses studied and could be successfully used to increase of width of leaves. Transgressive events in width of leaves are less pronounced than heterosis, but much more pronounced than those in the length. Direction of crossing affects the heterosis manifestations only of the length of the leaves but not those concerning their width. In terms to width of leaves, the manifestations of heterosis and transgression are related. Of all the studied variants, the one with the highest selection value regarding sizes of leaves is Hybrid 1555.