The internal transcribed spacer (ITS) and external transcribed spacer (ETS) regions of nuclear ribosomal DNA (nrDNA) in 30 species and four varieties of Chrysanthemum and 54 species and one variety in the closely related genera within the tribe Anthemideae, the family Asteraceae are sequenced and analyzed to clarify and justify their molecular characteristics and close relationships. Chrysanthemum forms a polytomy clade with Ajania. In addition, the substitution rates of the ITS and ETS regions of Chrysanthemum and Ajania are quite low as compared with the closely related genera. Chrysanthemum and Ajania are too close to separate from each other and have been currently, taxonomically treated as Chrysanthemum in combination. The species of Chrysanthemum studies are highly adapted and diversified with low level DNA divergence and thus, they might have reticulation and/or introgression event during evolutional process. According to the intergeneric mean of Chrysanthemum, a part of the radiate genera and species such as Ajania members studied, Elachanthemum intricatum and Phaeostigma variifolium are placed in the Chrysanthemum clade. However, C. sinuatum is excluded from this clade. The species of Chrysanthemum studied showed so close, relationships with cryptic differences in ITS and ETS with each other and thus, they could be distinctly separated from the other closely related genera in the tribe Anthemideae.

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Achillea millefolium L. collected in Altai, Russia showed 2n=54 as a hexaploid chromosme number. The interphase and metaphase chromosomes had FISH signals and DAPI bands: FISH yellow-colored signals of the 5S and 45S rDNA and the Arabidopsis-type telomeres were obtained after the hybridization of the biotin labbelled probes of the 5S, pTa71 and the Arabidopsis-type telomere sequence repeats. The 5S rDNA signals consisted of 11 yellow-color signals at the secondary constriction of the sat-chromosomes, two large interstitial signals on the long arm of two chromosomes, and very small four signals on the long arm of four chromosomes. The interphase nucleus showed 11 deep and two faint yellow color signals of 5S rDNA sites. Eleven yellow color signals of the 45S rDNA sites were detected on the short arm of 11 chromosomes. The Arabidopsis-type telomere signals were located on the terminal region on the both arms of chromosomes, while some were located far from the chromosome arm on the external part of the satellites in the sat-chromosomes, three terminal signals in some chromosomal arms one signal instead of two in the other chromosomes. DAPI-positive bands were found on interphase nucleus and 42 chromosomes, of which ten were terminal on both arms, four had two bands on a single arm, two had two bands on centromeric and terminal regions and 26 had single bands on a single arm. The 11 signals of the 5S and 45S rDNA sites and the the Arabidopsis-type telomere signals and DAPI bands performed variation in size and intensity

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Intergeneric F₁ hybrid between Chrysanthemum grandiflorum cv. 'Happy Gold' and Nipponanthemum nipponicum was made by the hand pollination. The F1 hybrids showed the maternal chromosome number of 2n=54. Applying the biotin labeled total genomic DNA of both parents without using blocking DNA showed that the whole chromosome complements of the hybrids were hybridized with the probes from both sides and colored green yellow color of FITC. The results indicated that the chromosome complement of the two genomes were closely related to each other. Nipponanthemum nipponicum could be one of the ancestors or closely related genome in particular to Chrysanthemum grandiflorum cv. 'Happy Gold.'

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Lychnis indica Benth. a member of the family Caryophyllaceae is commonly distributed in the temperate regions of the Himalayas. Two varieties- var. indica and var. fimbriata are recognized by Hooker in Indian taxa. Presently two accessions of var. fimbriata have been studied meiotically from Dalhousie Hills, Himachal Pradesh, India. Both the accessions uniformly exist at tetraploid level based on x=12 which is confirmed from the presence of 24 bivalents at metaphase I. The present chromosome count of n=24 is the first ever record for var. fimbriata. However, the same tetraploid chromosome number has been reported in the species from Kashmir Himalayas. In majority of the PMCs (pollen mother cells), the meiotic course is regular resulting into normal tetrad formation. However, some PMCs depict the phenomenon of cytomixis involving inter PMC transfer of chromatin material and associated meiotic anomalies. Chromatin transfer resulted into the formation of hypo- and hyper-ploid PMCs. Such PMCs results into the formation of pollen grains of heterogeneous sizes and some pollen sterility.

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