AUTOSEGREGATION AND LINKED-INHERITANCE IN AGAMOSPERMOUS PROGENY OF SUGAR-BEET BETA-VULGARIS L

The experimental data on autosegregation in parthenogenetic progenies of pollen-sterile sugar beet hybrids are presented. Three isozyme loci (Adh1, Idh3, and Me1) were used as genetic markers. The disomic gamet ic autosegregation for all three marker genes was observed. This indic ates that the megaspore mother cells in experimental plants had a doub le (tetraploid) chromosome complement. Diploid megaspores produce seed s by parthenogenesis. The autosegregation data indicate that the locus Me1 is inherited independently of two other markers (Adh1 and Idh3). Conversely, the loci Adh1 and Idh3 are linked with recombination coeff icient of 0.1655. The value of recombination coefficient between the t wo loci Adh1 and Idh3 estimated from the gametic autosegregation data coincides with that found earlier during the analysis of seeds with di somic zygotic segregation in the testcross progeny. Accordingly, the d isomic gametic autosegregation allows one to determine-the linkage rel ationships between marker loci and provides information on syntenic gr oups of genes.