The DNA content of polyploid filiar generation of 2n pollen. (a) Flow cytometry of nuclear DNA content of tetraploid hybrid 75# and diploid control (left black peak for control (2×), right gray peak for 75# (4×)). (b) Flow cytometry of nuclear DNA content of triploid hybrid 65# and diploid control (left gray peak for control (2×), right white peak for 65# (3×)). (c) Flow cytometry of nuclear DNA content of triploid hybrid 73# and diploid control (left black peak for control (2×), right gray peak for 73# (3×)).