Hybrydological analysis of inheritance of the chemical composition in Burley tobacco crosses. I. Nicotine and total nitrogen

Yovko Dyulgerski, Margarita Docheva

Abstract: The succession, the number of genes, the coefficient of heritability and the manifestations of heterosis, depression and transgression, related to the content of nicotine and total nitrogen in Burley tobacco have been analyzed. The Р1, Р2, F1 and F2 populations of six hybrid combinations have been studied. The obtained results show that the inheritance of the nicotine content in the studied crosses of Burley tobacco is overly dominant, incompletely dominant and additive dominant. The direction of inheritance is always in relation to a parent with a higher content of nicotine. The inheritance of the content of total nitrogen of Burley tobacco is incompletely dominant. The direction of inheritance is in terms of both options – to the parent with higher and to the parent with lower content of total nitrogen. The number of genes determining the manifestation of the sign total nitrogen content is much higher than the genes determining the content of nicotine. Heterosis manifestations with significant values were observed only in terms of nicotine content. This implies the use of heterosis for creating high nicotine hybrids in the first generation of Burley tobacco. Relatively low values of the coefficient of heritability have been established in respect to the nicotine content and even lower for the content of total nitrogen. For the determination of the studied indicators, the environment impact is crucial and the influence of genotype is less important. Related to the content of nicotine and sugars, the selection can begin in the late hybrid generations. The character of inheritance of the feature total nitrogen content is more complicated than the nicotine content.

Keywords: Burley tobacco; inheritability; inheritance; nicotine; total nitrogen

Date published: 2019-04-11