Discovery of a New Dominant Dwarf Gene in Maize and Its Preliminary Study

Based on the analysis of the population variations of plant height in hybrids including P1, P2, F1, F2, BC1 (backcrossed to dwarf parent) and BC2 (backcrossed to tall parents) derived from five cross combinations between a dwarf mutant of 52333 and tall inbred lines, the F1 individuals were as short as the short parent, and having no notable differences in contrast to control, and the segregation of the F2 generation appeared to be 3 ∶ 1, the dwarf F1 hybrids with the new dwarf gene were backcrossed with the tall inbred lines, the approximately segregation ratio of BC1 populations was 1 ∶ 1, and the off springs derived from that the combination of F1 with 52333, were all dwarf plants, so the dwarfing effect of this new gene was confirmed, indicated that the dwarf trait of 52333 was controlled by one dominant gene and its expression could not be affected by cytoplasm. Treating the pure dwarf plant and hybrid F1 with exogenous gibberellic acid at the sprout and seedling stages, the result proved that the dwarf gene was sensitive to gibberellin, so the dwarf gene maybe a new dwarf gene, and named it as D(t).