Chrysanthemum pulchrum (Ledeb.) Ling previously placed in Pyrethrum collected in (1) Russian Federation, Altai Republic, Altai Terr,, Kosh-Agacz District, Vicinity of Elongash River, 49°50’03”N, 088°02’96”E, alt. 2,450 m elevation; (2) Russian Federation, Altai Repiblic, Kosh-Agacz District, Mt. Talduair, 50°09’35”N, 089°23’53”E, alt. 2,300 m showed commonly the resting nucleus of the complex chromocenter type, the prophase chromosomes of the interstitial type, the chromosome number of 2n=18, and the typical diploid karyotype with 14 median- or submedian-centromeric chromosomes (of which two had satellites) and four subterminal-centromeric chromosomes (of which 1-3 had satellites). Those chromosome characters were same as those of the diploid species previously described.

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The ploidy level and the phylogenic position of Lachenalia congesta W. F. Barker (Asparagaceae) were analyzed by karyomorphological, molecular cytogenetical and molecular phylogenetical studies. The chromosome number of L. congesta was 2n=28, and these chromosomes showed bi-modal karyotype with four large sized chromosomes and 24 small sized chromosomes. The ploidy level of this species was diploid, because each two chromosomes made 14 pairs on the karyotype analysis by acetoorcein staining, DAPI staining and FISH methods. In addition two signals of 18S rDNA sites were detected by the FISH method supported this assumption. All 28 chromosomes of this species did not show any clear DAPI-positive bands and four signals of 5S rDNA sites were detected near the centromeres of small sized chromosomes. These characters were quite different from the characters observed by karyomorphological and molecular cytogenetical studies on common Lachenalia species with basic chromosome number of x=7 or 8. The data from molecular phylogenetic analysis of internal transcribed spacer (ITS) region supported this hypothesis.

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Nineteen strains of Zoysia sinica collected in Japan and Republic of Korea were investigated to clarify genetic diversity by molecular analysis with random amplified polymorphic DNA (RAPD). In six selected primers after initial screening using a total of 40 primers, altogether 22 reproducible RAPD fragments were amplified. Of these, 19 polymorphic fragments (86.7%) were observed in the range of 200-2000 bp in the 19 strains of the species. RAPD analysis in our study revealed genetic variation among Z. sinica strains with average pairwise distance of 2.77. The highest genetic distance of 3.74 with 14 character differences was obtained within strains from Republic of Korea and between another Korean strain and one Japanese strain from Kyusyu Island, while the lowest genetic distance with only one different character was obtained between the strains of Tsushima Island, Japan.

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The present paper deals with the cytological studies made on 30 populations of 26 species of the Gamopetalae from selected localities of Western Himalaya. The chromosome counts in Strobilanthes alatus (2n=16), Artemisia vestita (2n=36) and Ainsliaea latifolia (2n=16) were first ever cytological reports for the species. While, Bidens pilosa (2n=96) and Coreopsis lanceolata (2n=26) are new reports from India.

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Original chromosomes counts are reported for 13 populations of Stachys inflata Benth. (Laminoideae). All samples were collected from the West Provinces of Iran. Chromosome numbers in the species varied from 2n=2x=16 to 2n=4x=32. Five populations with chromosome number 2n=4x=32 were detected that was accordance with a unique existence prior report. A population with both diploid and tetraplod plants (2n=2x=16 and 2n=4x=32) was found in the studied area. The present finding of diploid plants of the species was documented here for the first time. Additionally, six populations that had both tripliod and tetraploid individuals (2n=3x=24 and 2n=4x=32) were also the first finding in this species. Another population of S. inflata showed intrapopulational three different chromosome numbers such as 2n=2x=16, 2n=3x=24 and 2n=4x=32 new and rare exceptional case. The results indicated that the intraspecific polyploidy was confirmed as the most significant evolutionary trend within this species.

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The present study has been carried out to access the mito-toxic effect of various concentrations viz.0.25%, 0.5%, 0.75%, 1% of herbicide (2,4-D) and pesticide (Endosulfan) on root tips of Hordeum vulgare. In the present investigation, a comparative cytological study has been done to study the effects induced by 2,4-D and Endosulfan on root meristems and it has been found that both herbicide and pesticide induced various types of chromosomal abnormalities such as laggard, precocious movement, stickiness, bridges, scattering etc. at higher concentration. The results revealed that pesticide (Endosulfan) is more mitodepressive and chromotoxic as compared to herbicide (2, 4-D) as it resulted in high level chromosomal damage. Both have a dose dependent impact on the mitotic index. Scattering is the common chromosomal aberration prevalent among them.

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Cytogenetical investigations have been carried out on Hordeum vulgare. Seed of H. vulgare were treated with different concentrations (0.1, 0.2, 0.3, 0.4 and 0.5%) of ethyl methane sulphonate (EMS) and hydrazine hydrate (HZ). The plants in the treated populations showed varying degrees of meiotic irregularities almost at all the mutagenic concentrations. The frequency of meiotic irregularities was found to be more in HZ treatment than EMS. The various types of meiotic abnormalities such as univalents, multivalents, stickiness, precocious movement, stray bivalent, non-orientation, cytomixis, laggard, bridges, unequal separation, micronuclei and disturbed polarities were observed. Taking the percentage of meiotic abnormalities and pollen sterility as an index of effectiveness of a mutagen, HZ treatment was found to be more effective.

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