Agricultural Institute, BG-9700 Shumen, Bulgaria
KIKINDONOV, G., 2009. Simple and triple-cross hybrids sugar beet hybrids. Bulg. J. Agric. Sci., 15: 20-25
The use of monogerm pollen sterility lines as maternal components of sugar beet hybrids allows full hybridization in the technical seed production. Because of the long-term self-pollination and the narrow genetic basis the male sterile lines are still with lower productivity, quality parameters and disease resistance. Test results of simple and triple-cross hybrids of six MS lines with two diploid and two tetraploid multigerm pollinators have been discussed. The participation of a second “O” type in maternal components’ breeding scheme increases to some extent the productivity of the MS-simple hybrids because of the increased heterozygousity, but this does not reflect in relatively higher productivity and quality of the triple-cross hybrids - diploid and triploid. The differences between the simple and the triple-cross hybrids of sugar beet are due to the different combining ability of the parents in the respective crosses. The conclusion is that the inclusion of second “O” type in the sugar beet breeding scheme is not expedient, because this does not bring to higher productivity and quality of the raw material of the triple-cross sugar beet hybrids.