Question

In a cross between Raphanus 2n=18 and Brassica 2n=18, the progeny would have.......chromosomes.

• A. 36
• B. 18
• C. 9
• D. 27

Answer 1

The correct option is A 36

In autopolyploids there is multiplication of the same genome. They are commonly seen in Triticum, Solanum, Rosa and many other plants.

The allopolyploids arise from a heterozygote. They possess multiples of non-homologous chromosomes.

Example- Raphanobrassica, Triticale. Both these plants are allopolyploids.

The Raphanobrassica resulted from a cross between Raphanus sativus (2n=18) and Brassica oleraceae (2n=18). So, the Raphanobrassica will be tetraploid and have 36 chromosomes.

The Triticale arose from a cross between Triticum and Secale.
Brassicoraphanus or Raphanobrassica is the name for all the intergeneric hybrids between the genera Brassica (cabbages, etc.) and Raphanus (radish). The name comes from the combination of the genus names.