THE EFFECT OF BACKCROSS METHOD IN TOBACCO BREEDING

Abstract The paper encompasses investigations of four oriental tobacco varieties (P10-3/2, P-23, P-84 and YK 7-4/2) and their diallel F1, F2, BC1 (P1) and BC1 (P2) crosses in the course of 2016 and 2017, for the characters leaf number per stalk and dimensions of the middle belt leaves. The research was carried out on the experimental field of the Scientific Tobacco Institute - Prilep in randomized block system with four replications. The measurements were made in the stage of rapid growth (butonization), and the values obtained were processed by variational-statistical analysis. Heritability (h2) of the traits was calculated using the Mather and Jinks method. The aim of the research is to study the effect of backcross breeding on improving the quantitative traits of tobacco, to open up the possibility of selecting individuals at the maximum number of crosses enabled by the diallel of parental genotypes and to offer directions for further selection. The obtained results showed different modes of inheritance in all generations studied. Heritability of the crosses was over 95%, which is a sign of high heritability of the studied traits. The offered pattern for further successive selection can also be used for other plant species to improve a range of traits, including resistance to diseases.