GENETIC-CONTROL OF ENDOSPERM BALANCE NUMBER (EBN) IN THE SOLANACEAE BASED ON TRISOMIC AND MUTATION ANALYSIS

The genetic control of Endosperm Balance Number (EBN) was studied usin g trisomics and induced mutation. In order to induce and detect a chan ge in a factor determining the EBN of the male, pollen from tetraploid Datum was irradiated and used to pollinate diploids. No triploids wer e produced in over 70 000 fertilizations. At least 70 would have been expected if the deletion of the function of a single gene could change the EBN. An attempt was made to find a particular chromosome that cou ld alter the EBN of the female when it was present as the extra chromo some in 2x+1 X 4x crosses. In tests of trisomics in both Datura and So lanum (potato) no chromosome could be found that changed the EBN. Ther efore, it is concluded that more than one gene and more than one chrom osome is involved in determining EBN.