Occurrene of aneuploid progenies from an asynaptic amphidiploid of Scilla scilloides (Lindley) Druce. I. Chromosome constitutions and reproductive properties of both parental and progeny plants.

Abstract

One diploid plant with 2n=18 and 26 aneuploids with 2n=37 to 60 of different ploidy levels were obtained among open-pollinated progeny plants from the asynaptic amphidiploid plants (2n=34+4f+2F, AABB) of Scilla scilloides.This species is a long-lived perennial herb propagating vegetatively by bulb multiplication, as well as sexually by seed production. On the both parental and progeny plants, reproductive properties were analyzed in comparison with those of the normal amphidiploid plants. In the parental asynaptic plants, the majority of pollen grains revealed a very low fertility which varied slightly among clonal plants and years, the average value being 5.50%. The seed setting rate was vely low, the average value being 1.8% in 1969, and 1.2% in 1970. Some of the seeds germinated in the following spring. Thus, asynaptic plants were capable of sexually producing a few progenies. They have also produced on the average 16.7 bulblets during ten years. As for the progeny plants with various chromosome numbers, the pollen fertility was greatly variable among plants, from 10.3 to 96.0%. The seed setting rate and germination rate were considerably variable among progeny plants, and were, as a whole, lower than those of the normal amphidiploid plants, similar to the case of pollen fertility. All progeny plants reproduced also vegetatively during 16 or 17 years.