Cystopteris fragilis collected in Mongolian Altai showed three cytotypes with chromosome numbers of tetraploid (2n=c.168), pentaploid (2n=c.210) and hexaploid (2n=c.252). Flow cytometry analysis also showed three different peaks of DNA contents of nuclei in fronds. Meiotic metaphase chromosomes of the spore mother cells in the tetraploid and hexaploid C. fragilis showed all bivalents with c.84_II and c.126_II, while those of the pentaploid C. fragilis showed many univalents and bivalents that produced mostly sterile spores. The pentaploid C. fragilis was suggested to be a hybrid between the tetraploid and the hexaploid C. fragilis.

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Ten species of Saxifraga were collected in Russia and Mongolia, and observed their somatic chromosome numbers. The chromosome number of 2n=30 for S. manchuriensis, that of 2n=114 for S. hieracifolia, that of 2n=48 for S. sibirica, that of 2n=28 for S. oppositifolia, and that of 2n=70 for S. terektensis were reported here for the first time. The chromosome numbers for the other five species such as S. aestivalis, S. serotina, S. hirculus, S. flagellaris and S. cernua verified the previous counts. Chromosome sizes of ten species varied from 4.3 to 1.02 μm long in average. Saxifraga aestivalis had bi-modal decrease in chromosome size from the largest to the smallest chromosomes while the other nine species had mono-modal decrease in chromosome size

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Tridactylina kirilowii (Turcz. ex DC.) Schultz-Bip., the Anthemideae Cass., Asteraceae displayed the chromosome number of 2n=18 for the first time. The chromosomes of the species at mitotic metaphase were characterized by chromosome size, centromeric position, distribution of the G-C and A-T heterochromatin-rich regions by aceto-orcein, CMA, DAPI, and FISH. The smallest chromosome at mitotic metaphase was approximately 4.1±0.5 μm, while the largest chromosome was 6.9±0.7 μm. The total length of the chromosome complement at mitotic metaphase was 97.5±7.9 μm. The chromosome complement at mitotic metaphase showed 16 median-centromeric chromosomes and two submedian-centromeric chromosomes. The CMA stained the whole chromosomes, and showed four brighter bands on the terminal positions of four chromosomes and were convenient with the four sat-chromosomes. DAPI stained the whole set of the chromosomes at mitotic metaphase, while CMA-DAPI positively, brightly stained some heterochromatin regions in the chromosomes at mitotic prometaphase Applying FISH using the digoxigenin labeled pTa71 probe of 45S rDNA to sets of the mitotic chromosomes showed four red colored signals that were located at the terminal region displayed after hybridization of the probe with four median chromosomes at mitotic metaphase.

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RAPD analysis was carried out using to infer the characteristics of RAPD generated DNA fragment and to investigate phylogenetic relationships in three species of D. spatulata complex with different types of genome compositions and ploidy levels. A total of 60 decamer random sequences were initially screened to select using analysis primers. The result of RAPD analysis in the present study showed that D. rotundifolia and D. tokaiensis clustered more closely than D. spatulata. Thus, DNA fragments obtained from RAPD primer might have a priority to amplify certain DNA from the haploid genome set with larger chromosome size than that of smaller size in Drosera spatulata complex species.

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