Hybrydological analysis of inheritance of the chemical composition in Burley tobacco crosses. II. Sugars and proteins

Yovko Dyulgerski, Margarita Docheva

Abstract: Inheritance, manifestations of heterosis and transgression, coefficient of heritability, number of genes involved in the formation of contents of sugars (soluble carbohydrates) and proteins in Burley tobaccos are studied. For that purpose, the Р1, Р2, F1 and F2 populations of six hybrid combinations are studied. The results obtained show that the inheritance of the content of sugars in the tested crosses Burley tobacco is monogenic overdominant or incomplete dominant. Direction of inheritance is always in respect of the parent with the lower values. Direction of crossing has a strong influence on inheritance and manifestations of heterosis and depression on the content of sugars. Very low values of the coefficient of heritability indicate that in determination of this trait environmental influence is decisive. In this case selection of the desirable trait can begin in late hybrid generations. Inheritance of protein content in the studied hybrid combinations Burley tobacco is incomplete dominant except Hybrid 1483A, where it is overdominant. The direction of inheritance is equal in respect of the parent with the higher values in relation to a parent with a lower content of proteins. The number of genes determining the expression of the protein content is high and fluctuates depending on the crossing. The direction of hybridization slightly influences by inheritance and manifestations of heterosis, depression and transgression of the protein content. Averages of coefficient of heritability regarding of proteins content are observed. In determination of this feature the effects of genotype and environment are almost in the same proportion.

Keywords: Burley tobacco; inheritability; inheritance; proteins; sugars

Date published: 2017-03-30