On the relation between geographic races and polyploidy in silene ciliata pourr
- Cite this article as:
- Blackburn, K.B. Genetica (1933) 15: 49. doi:10.1007/BF01591850
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Silene ciliata is an ancient species with discontinuous geographical distribution breaking it up into two distinct subspecies,S. ciliataPourr. andS. graefferiGuss., in the Spanish area and Italy with the Balkan Peninsula respectively.
Variation in the Italian race is concerned mainly with differences in size between different stocks, though there are differences in leaf form hairy covering and flower colour.
The Spanish race is extremely variable in all features even between different members of the same family.
In the Italian race diploids and tetraploids occur and since all tetraploids examined are larger than the one diploid stock it is assumed that some gigantism is present.
In the Spanish race very similar plants may have diploid, tetraploid or 16-ploid complements, showing a lack of the gigas condition but, actually, the largest individual plants seen were among the 16-ploid stocks.
One of the Italian tetraploid stocks shows more variation than the others and it has been found to contain plants with 49 and 50 chromosomes as well as the normal 48 of the tetraploid.
A plea is put forward for gifts of more material, particularly seeds, in order to clear up the many doubtful points in the situation.