Variegata Tobacco

[madhouse]

Hi Bob the plants that show a variegation have it all over, but from the seeds sown there are all-ways about 60% of seedlings showing the variegation and 40% that have pure green foliage but the green ones still tend to produce variegated seedlings of a similar percentage ?.

 

[deluxestogie]

I'm going to take a guess, and suggest that if you intentionally crossed these with a variety that never shows variegation (say, a normal Samsun), only the female variegated parents (made by removing its anthers, providing pollen from the male parent, then sealing the blossom) would provide you with the 60% variegated seedlings, and that female normal variety parents would yield 0% variegated seedlings. That is, the pollen from the variegated plant would not yield any variegated seedlings when pollinating a normal Samsun female.

In keeping with Jessica's comments, the defect may be passed only in the cytoplasm (which always comes from the female parent), rather from the nucleus. So it doesn't follow basic Mendelian inheritance patterns.

I think it would be a bit tedious to actually do the crossing experiment on enough specimens to give meaningful numbers.

Bob

 

[JessicaNicot]

I'm going to take a guess, and suggest that if you intentionally crossed these with a variety that never shows variegation (say, a normal Samsun), only the female variegated parents (made by removing its anthers, providing pollen from the male parent, then sealing the blossom) would provide you with the 60% variegated seedlings, and that female normal variety parents would yield 0% variegated seedlings. That is, the pollen from the variegated plant would not yield any variegated seedlings when pollinating a normal Samsun female.

In keeping with Jessica's comments, the defect may be passed only in the cytoplasm (which always comes from the female parent), rather from the nucleus. So it doesn't follow basic Mendelian inheritance patterns.

I think it would be a bit tedious to actually do the crossing experiment on enough specimens to give meaningful numbers.

Bob

you are a clever man with your reciprocal crossing schemes! and you very well may be right.

 

[madhouse]

I'm going to take a guess, and suggest that if you intentionally crossed these with a variety that never shows variegation (say, a normal Samsun)

Bob i have never crossed these just bagged them every year.