Question

A large plant arose in a natural population. Qualitatively, it looked just the same as the others, except much larger.
A) Is it more likely to be an allopolyploid or an autopolyploid?
2) How would you test that it was a polyploid and not just growing in rich soil?

Answer 1

A) If the qualitative features of the large plant is same as others then it is more likely autopolyploid because

a) Autopolyploids are formed due to derived multiple set of chromosomes from same parental species

b) Allopolyploids are formed due to derived muplitiple set of chromosomes from different species.

Autoploids are qualitatatively same due to similar genetic architecture with the parental species except few benefficial genes which helps for fitness.

Allopolyploids looks phenotypically different from the patental species as they are derived from the two different species.

2) How would you test that it was a polyploid and not just growing in rich soil?

Meiotic profiles of pollens from normal and large plants can be evaluated under microscope for ploidy testing. Flow cytometric analysis of DNA content can also be used to do ploidy testing of large plant.