Identification of donor lines containing favorable alleles for quantitative traits in burley tobacco (Nicotiana tabacum L.)

The objective of this study was to identify the best burley tobacco (Nicotiana tabaccum L.) line among a group of four lines from germplasm collection, for improving an elite single hybrid Bols 335 x TN 86. Values of three quantitative traits (number of leaves, total leaf area and leaf yield) were measured in two-year field experiment. Evaluation of donor lines as sources of new favourable alleles not present in the elite hybrid parent lines was conducted. According to Dubley (1984, 1987) the most significant class for improving quantitative traits is locus class G. Donor line TN 90 had positive values of the parameter microG for number of leaves and for total leaf area. Studied donor lines could not be use directly as the source of new alleles for the improvement of leaf yield in elite hydrid. The improvement of leaf yield in tobacco hybrid Bols 335 x TN 86 would be conducted indirectly via back crossing (TN 86 x TN 90) x TN 86. Significance of genotype environment interaction for studied traits indicates the same breeding method would be effective in broad range of environmental conditions.