Scientific Journal of KubSAU

The article presents the results of the genetic analysis of the trait ‘plant height’ for six crosses involving the forms related to different subspecies of rice. There have been estimated the types of inheritance and a number of genes, which assist to determine this quantitative trait. We have found out that the variance of the trait ‘plant height’ is determined by 3-5 pairs of genes having additive and dominant activities and the degree of dominance reduces in case the variance among parental forms increases. The non-allelic interaction of the genes of the initial forms produces transgressive dwarf and tall forms. The cross ‘Lampo’x’Virazh’ showed the highest degree of transgression in ‘plant height’ due to short height of both parental forms (61.7%), but the frequency of transgression was larger than that of the cross ‘Lampo’x’Komandor’(17.6%). This combination (‘Lampo’x’Komandor’) produced more tall forms (up to 135 cm). The segregation of a great number of tall forms into F2 testifies that the parental forms of these hybrids vary in the allelic state of several pairs of genes, whose various combinations form phenotypes with a longer stem. Thus, the semi-dwarf feature of the varieties ‘Lampo’, ‘Komandor’ and ‘Virazh’ is determined by various non-allelic genes