Genetic diversity of Satakentia liukiuensis in some cultivated individuals in Bogor Botanical Garden (Indonesia) and Nong Nooch Tropical Garden (Thailand) compared with natural population was analyzed by RAPD markers. Satakentia liukiuensis is a monotypic genus and an endemic palm species in Japan and it distributed in very restricted area in Ishigaki Island and Iriomote Island in Yaeyama Group of the Ryukyu Islands. The ten of RAPD primers (Operon Tech. Inc.) were used in RAPD analysis generated 82 amplifi ed bands, which is 27 bands (32.9%) were polymorphic. A phenogram generated by UPGMA clustering analysis shows all accessions from natural population were separated from cultivated individuals with genetic distance 0.104. Genetic variation among accessions in natural population was lower than cultivated individuals. The genetic uniformity of S. liukiuensis in natural population may due to the result of the inbred nature of its small population size for a long time. In our opinion, the existence of S. liukiuensis will be sustainable, since the natural population of the species in Ishigaki Island was established as protected areas and managed by Satake Corporation and also the corporation announced and built `The Toshihiko Satake Memorial Palm Museum` in natural locality sites of the species. RAPD method is a very fast way of obtaining genetic information and the methods require no prior knowledge of the DNA sequence to generate genetic markers.

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Natural variation in recombination frequency in Eclipta alba has been assessed by analyzing chiasma frequency variation among three morphologically diverse morphotypes i.e. erect, intermediate and prostrate. The study revealed that the chiasma frequency varied between 18.8-21.4, 18.9-20.9 and 19.3-21.7 in the three morphotypes, respectively. It is found that the chiasmata frequency for prostrate type remain higher throughout the year in comparison to intermediate and erect types. There was no significant variation in mean chiasma frequency between plants within accessions, but there was significant variation between accessions. Presently observed the cyclic variation in the average chiasma frequencies, recombination index and excess chiasma in the three morphotypes of Eclipta alba clearly depict the influence of environmental factors on the process of recombination.

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Mucuna Adans. is a large genus with more than 150 species of annual and perennial legumes of pantropical distribution. Despite considerable economic importance of some of its species, almost no work has been done on their cytogenetic characterization in any part of World. In this paper, we have presented a first report on karyomorphological analysis in four Indian species viz., Mucuna atropurpurea, Mucuna monosperma, Mucuna nigricans and Mucuna pruriens bringing out diploid number for M. atropurpurea and karyotypic formula for all the four species. Root tips were treated with 0.002 M 8-hydroxyquinoline and temporary preparations were made after squash in aceto-carmine. Karyomorphological description for each of the species has been detailed taking into account the following features: chromosome number, total length and relative length, arm ratio of each chromosome, haploid set length and degree of asymmetry. Mitotic metaphases in all the species showed 2n=22 chromosomes. Mucuna nigricans showed two pairs of sat-chromosomes. None of the species, however, revealed identical karyotypic formula indicating occurrence of rearrangements. The haploid set length of annual M. pruriens was found to be reduced in size when compared to perennial species pointing its evolution from the latter.

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Traditionally, tetraploids have been generated asexually using a genome-doubling agent, such as colchicine. Seeds and apical buds of seedlings of sesame (Sesamum indicum L., 2n=26) were treated with colchicine solutions of different concentrations for different durations. No polyploidy could be obtained in the seed treatment process, while Seedling treatment resulted in five autotetraploid plants at 0.5% concentration for 3 consecutive day's treatment along with the recovery of 12hrs each day. The morphology (plant height, number of branches, number of capsules, days to flowering, days to maturity, seed weight etc), cytology, pollen fertility and seed setting of induced autotetraploid plants (4n=52) and diploids (2n=26) have been analyzed. Pollen fertility and stomatal frequency registered a decrease over diploids while size of pollen grain and stomata increased in the autotetraploids. Meiotic studies of the autotetraploids revealed a number of uni-, bi-, and multivalents. The present study was undertaken to induce genome doubling in sesame under green house conditions, so as to develop a suitable protocol for the maximum recovery of autotetraploids and an economic use of colchicine.

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Present paper deals with the cytological evaluation of one species each belonging to 9 different genera of 6 families of Polypetalae from three selected areas such as Kashmir and distantly located Districts Kangra and Sirmaur of another state Himachal Pradesh from Western Himalayas. The chromosome numbers have been recorded for the first time on worldwide basis for the species, Parthenocissus semicordata (n=24) and Silene moorcroftiana (n=24). Filipendula vestita forma vestita with haploid chromosome number, n=7 has also been worked out for the first time. The present chromosome number n=14 for Lathyrus aphaca adds a new tetraploid cytotype to already reported diploid ones. In addition, new aneuploid cytotypes have been worked out for the first time for Desmodium microphyllum (n=10), Impatiens laxiflora (n=8), Ranunculus diffusus (n=14), Thalictrum foetidum (n=8) and Vicia tetrasperma (n=6). The presence of B- chromosomes (0-1B) also makes the first report for the species, Ranunculus diffusus.

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