| Abstract: | New chromosome counts for 9 species and 2 genera of Sapindaceae are presented and compared with a review of all available chromosome numbers of the family. In 4 species diploid numbers differing from previous reports are found. In 4 species of the tribe Paullinieae (S. diversiflora, S. subdentata, C. grandiflorum and C. halicacabum) detailed studies on interphase nucleus structure, condensing behaviour and chromosome banding patterns are presented. The karyological differentiation of Paullinieae is generally characterized by dysploid reduction of chromosome numbers and the increase of chromosome size. Sequential staining of nuclei with CMA/DAPI and Giemsa-C-banding demonstrates diversification of constitutive heterochromatin (= hc) and different types of chromatin organization in Serjania and Cardiospermum. The obvious lack of polyploid series and the karyological evolution within the family is discussed. The outstanding small genome size found in Cardiospermum halicacabum is considered to be due to a secondary loss of DNA in the course of the change to herbaceous growth. |
