RE:Genetics- Swertii and aplhylla

The plant could very well have all the plant characteristics of pallida and genes of aphylla. There is a lot of plant characteristics inherited through the cytoplasm. For reference reed Verne Grants book "Genetics of Flowering Plants" section on cytotoplasmic inheritance.
Swertii is a triploid with count of 38 chromosomes. Most triploids are from tetraploid pollen on diploid pod plant. A first generation triploid would have 36 chromosomes. During meiosis the paired chromosomes separate just fine. The unpaired 12 can be randomly pulled into the gamettes from none to all 12. The gametes would be basically diploid gametes with 12 + 2 genes in this example. According to Kidd BAIS issue #193 the number of supernumery chromosomes is most likely to be between 1-4.  The pollen of triploids are for all intense and purpose is sterile. Thus the original triploid would be the pod parent of the second generation plant. Thus it very well could be that Swertii is a second generation triploid with 2 supernumery chromosomes. That is they add to the count but are none essential. Thus pallida could be the original pod parent and contribute the cytoplasm that gives a lot of the plant characteristics. The plant then would have a parent and a grandparent that is a tetraploid. Aphylla could very well be this tetraploid. Cytoplasm from pallida could very well be the dominant force providing the observed plant characteristics.

Are there any other possible scenarios of this chromosome count that anyone is aware of?

Chuck Chapman

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