1. Allopolyploids combine the morphological and physiological characteristics of the parent species but it is very difficult to predict the precise combination of characters that would appear in the new species.
2. Many allopolyploids are apomictic

Ex : Tulips, Solanum

3. The chromosome pairing in the new species depends upon the similarities between the chromosomes of the parental species. Chromosomes with such similarities are known as homoeologous chromosomes. After chromosome doubling, the allopolyploid would have two homologous chromosomes for each chromosome present in the F1 hybrid, comparable to the diploid species. Such allopolyploid is referred as amphidiploid or Allotetraploid.
4. Fertility of Allopolyploids can be improved by hybridization and selection.