allotetraploid

An allopolyploid that has originated from an interspecific hybrid through the formation and fusion of unreduced diploid gametes. An example is Raphanobrassica, which is obtained by crossing Raphanus sativus (radish) with Brassica oleracea (cabbage). The F₁, is sterile but diploid gametes are sometimes formed, which on selfing give a fertile tetraploid F₂. See allopolyploidy.