1989 年 54 巻 4 号 p. 661-666
The cytology of Solanum jasminoides var. grandiforum has been investigated. The root tip cells showed 10 homologous pairs and two heteromorphic pairs of chromosomes. The pollen mother cells showed one or two rings or chains of four chromosomes, indicating segmental interchanges in the taxon. The heteromorphism in two pairs of chromosomes is shown to be the result of one of the two interchanges. Various abnormalities such as chromosome lesions, asynapsis, chromosome breakages in prophase and chromatin bridges at anaphase stages were also observed in the PMCs. Only about 20% of the pollen grains were stainable. The plant was completely sterile without fruit set.
The cause of abnormalities in chromosome behaviour in S. jasminoides is not clearly known. The irregularities in meiosis found in the taxon are attributed to the two interchanges and consequent changes in the location of controlling sequence which effects related genes controlling meiotic events in a co-ordinate fashion.