CYTOLOGIA
Online ISSN : 1348-7019
Print ISSN : 0011-4545
Volume 38 , Issue 3
Showing 1-18 articles out of 18 articles from the selected issue
  • Thomas E. Jensen, Linda M. Sicko
    1973 Volume 38 Issue 3 Pages 381-391
    Published: September 25, 1973
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    The effects of 0.02 sodium acetate on the ultrastructure of Chlorogloea fritschii are described. Control cells contain the usual inclusions found in blue-green algae. These include structured granules, polyhedral bodies, β granules, thylakoids, ribosomes and areas of DNA. In addition, poly- β-hydroxybutyrate (PHB) gra-nules are present. In control cells these granules are quite small being approxi-mately 100mμ in diameter. They are either elongate or spherical in shape. The elongate PHB granules are limited by an 80Å thick membrane while the spherical granules are bound by a 30Å thick membrane. In material treated with sodium acetate the PHB granules increase in diameter while they decrease in number. However, there is an overall increase in the volume of the cell occupied by the granules. In addition to an increase in PHB, polyphosphate bodies also develop in the cells beginning one day after exposure to sodium acetate. The number of thylakoids in the cells decreases in material exposed to sodium acetate. After three days exposure to sodium acetate β granules also appear to accumulate phos-phate as they exhibit the characteristic sublimation in the electric beam.
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  • B. S. Gill, Abha Chawla, Rup Kanwal
    1973 Volume 38 Issue 3 Pages 393-401
    Published: September 25, 1973
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Cytological studies on 22 species of Euphorbiaceae from North-West India have been made. Of these Euphorbia prolifera (n=14), Andrachne cordifolia (n=11) are being counted for the first time. Additional intraspecific cytotypes have been detected in Euphorbia milii with n=21, E. neriifolia with 2n=80 and E. pul-cherrima with n=15. Four cytotypes with 2n=60, 80, 100, 120 have been recorded in Codiaeum variegatum. Euphorbia neriifolia, Codiaeum variegatum and Achlypha wilkesiana are the polyploids with abnormal meiosis. The cytotype with n=15 of yellow variety Euphorbia pulcherrima is a tetrasomic derived from one with n=14.
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  • Vl. Co-existence of Rattus rattus with 38 and 42 Chromosomes in South Western India
    S. C. Lakhotia, S. R. V. Rao, Suresh C. Jhanwar
    1973 Volume 38 Issue 3 Pages 403-410
    Published: September 25, 1973
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Chromosomes of two subspecies of Rattus rattus, namely, R.r. wroughtoni and R.r. rufescens, from Sagar, Mysore State, South Western India, have been examined. R.r. wroughtoni has 42 chromosomes typical of Rattus rattus, while R.r. rufescens shows 2n=38. The karyotype of the latter is similar to that described by other workers for Rattus rattus populations with 2n=38 from other parts of the world. This is the first report of Rattus rattus with 38 chromosomes from India. It is proposed that the 2n=38 karyotype is evolved from the basic Rattus rattus karyo-type with 2n=42 by centric fusion and pericentric inversions.
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  • B. S. Gill, H. L. Sharma, Jagtar S. Dhesi
    1973 Volume 38 Issue 3 Pages 411-416
    Published: September 25, 1973
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Three haploid-diploid plants were identified in pearl millet. The haploid were clearly distinguished from reduced size of the plant, thin stem, small and narrow leaves, and small and thin spike. Chromosomal association of 2II+3I was most common suggesting the basic number of genus, Pennisetum, as five.
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  • M. C. Joshi, K. P. S. Chauhan
    1973 Volume 38 Issue 3 Pages 417-424
    Published: September 25, 1973
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Studies on intranuclear distribution of chiasmata were carried out in two types of plants of Pisum sativum, var. T 163-1) normal diploids and 2) interchange hetero-zygotes. In most of the plants the chiasmata were found to be distributed in an uncorrelated manner among the different bivalents of a cell. This was ascribed to the highly symmetrical karyotype possessed by Pisum sativum.
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  • A. P. Jha, S. M. Z. Rahman
    1973 Volume 38 Issue 3 Pages 425-436
    Published: September 25, 1973
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Drosophila malerkotliana differs from Drosophila bipectinata in the presence of seven paracentric inversions, three on the second and four on third chromosomes. The three inversion complexes have been analysed on the basis of the reference map of the salivary gland chromosomes of D. malerkotliana. The probable course of events in the evolution from the common ancestral population, have been discussed. The F1 hybrids are sterile when crossed among themselves.
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  • K. C. Gupta
    1973 Volume 38 Issue 3 Pages 437-447
    Published: September 25, 1973
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    The cytology of fenugreek calli from the primary culture and 12th subculture was studied. Cytometry and karyometry revealed a greater range of variation in the primary culture than in the subculture. In general mitoses were normal irrespective of their ploidy. Infrequently multinucleate cells, apparent nuclear fusion or fission, bridge formation at ana-and telophases were also observed in both the cultures.
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  • G. S. Hicks, T. A. Steeves
    1973 Volume 38 Issue 3 Pages 449-453
    Published: September 25, 1973
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Superficial cells of the shoot apex of Osmunda cinnamomea adjacent to leaf primordia were examined with the electron microscope. In this region, a develop-mental interaction is known to occur between the shoot apex and prospective leaf cells. Numerous plasmodesmata were observed in the anticlinal and periclinal walls of these promeristem cells. It is suggested that the plasmodesmata might constitute a transport pathway for developmental influences passing from the promeristem to the leaf site.
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  • R. A. Singh, M. S. Pavgi
    1973 Volume 38 Issue 3 Pages 455-466
    Published: September 25, 1973
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Morphology, cytology and development of Melanotaenium brachiariae Viégas parasitic on Brachiaria distachya (L.) Stapf have been described. The diploid fusion nucleus divides in the promycelium during teliospore germination. The first divi-sion is reductional followed by an equational one. Some stages in sequence of the meiotic division have been observed and the haploid chromosome complement determined at metaphase (n=5). The promycelium bears a cluster of terminal sporidia, each bearing a whorl of secondary sporidia, which detach and conjugate to initiate the dikaryophase. Several aberrations in the teliospore germination and nuclear behaviour are also observed. Sporidial development and their conjugation indicate that the fungus possesses haplobiontic: diplobiontic life cycle pattern. Development of parasitic mycelium and teliospores in the host leaves has been described. The mycelium is intercellular, branched, dikaryotic and devoid of haus-toria. Teliospores develop by enlargement of secondary hyphal cells in the mesophyll of the leaf tissues.
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  • A. N. Mukhopadhyay, M. S. Pavgi
    1973 Volume 38 Issue 3 Pages 467-477
    Published: September 25, 1973
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Observations are presented on the cytological behavior of Protomyces macro-sporus Unger in artificial culture and within an infected coriander (Coriandrum sativum L.) stem. The haploid spores bud into colonies with mitoses. Diploid condition is brought about by copulation between 2 compatible haploid spores accompanied by nuclear fusion. The diploid spores only are pathogenic to the host producing branched, septate hyphae with multinucleate cells in the inter-cellular spaces of nonvascular tissues in the host. Hyphal development initiates in vitro chlamydospore formation similar to that within the host tissues, thus in-creasing the primary inoculum potential of the pathogen. The haploid chromosome complement of n=2 is confirmed again.
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  • Wolfgang Scheuermann, Henning Gaude
    1973 Volume 38 Issue 3 Pages 479-484
    Published: September 25, 1973
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    The investigation was directed to give information about a possible DNA loss during in vivo isolation of nuclei from the Vicia faba root-tip meristem, using the isolation method from Kuehl. The relative DNA-content of isolated nuclei was compared with that of nuclei from squash preparations by means of Feulgen-micro-photometry.
    As statistical problems nearly become unsurmountable measuring all nuclei phases, and as there is a selection of special nuclei phases during isolation, S-phase nuclei were labelled by incorporating 3H-thymidine. The measurement only of unlabelled nuclei leads to pure G1- and G2- phase values. The finding, that isolated nuclei have maximal 4% lower values than nuclei fixed in situ, can hardly be inter-preted as a real DNA loss, because of systematic errors originating from the methods.
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  • Barry Thomas
    1973 Volume 38 Issue 3 Pages 485-495
    Published: September 25, 1973
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    A karyological investigation of Peromyscus found upon the islands along the coast of British Columbia, Canada, has revealed two karyotypic patterns. These two karyotypes correlate with both morphological and reproductive patterns exist-ing among these island populations. This evidence has led me to revise the taxo-nomy so that the large morph with the high F.N. karyotype is classified as Pero-myscus sitkensis and the small morph low F.N. karyotype remaining Peromyscus maniculatus.
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  • Y. C. Ting
    1973 Volume 38 Issue 3 Pages 497-500
    Published: September 25, 1973
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    At pachytene stage of the microsporocyte divisions of haploid maize, most of the chromosomes formed foldback-type of nonhomologous associations. Sub-sequently, no evidence of crossing overs relating to this type of associations has been obtained. However, synaptonemal complexes were consistently present. Therefore this report is to extend my previous view that synaptonemal complex does not necessarily lead to crossing overs but is a product of pairings.
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  • B. B. Chimphamba
    1973 Volume 38 Issue 3 Pages 501-514
    Published: September 25, 1973
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    The karyotype analyses of the Evansia species did not suggest any simple explanation for the origin of the progressional series of chromosome numbers of 2n=26, 28, 30, 32, 34, 36, 42, 44 and 54. A comparison of the karyotypes of geographically adjacent species showed that an increase in chromosome number was accompanied by a decrease in chromosome size. Karyotype differnces did not always suggest lack of affinity between species as was shown between I. japonica and I. confusa which formed fertile hybrids although their karyotypes were very different. The hybrids between I. japonica and I. confusa vary in their chromosome numbers from 2n=39 to 2n=43. The karyotypes of I. wattii and I. confusa showed greater similarities, a correspondence paralleled by their successful hybridization to form F1 hybrids. I. wattii could represent a subspecies of I. confusa. Meiotic divisions in the available clones of I. wattii and I. japonica showed that these 2 species were atypical in that the latter was possibly a triploid and the former the product of a chromosomal interchange.
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  • Fathi Abdel-Hameed
    1973 Volume 38 Issue 3 Pages 515-519
    Published: September 25, 1973
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Postmeiotic polymitoses were observed in reciprocal interspecific hybrids be-tween two diploid Clarkia species, i.e., C. lassenensis×C. amoena huntiana. These supernumerary mitoses following meiosis are similar in their general features to those previously observed in maize and spider plant (Beadle 1931, Koul 1970). In Clarkia interspecific hybrids, however, the genetic system responsible for these polymitoses is most likely not a simple recessive gene as is the case in maize but rather genic disharmony between the two parental sets of chromosomes.
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  • A. Crosby Longwell, S. S. Stiles
    1973 Volume 38 Issue 3 Pages 521-533
    Published: September 25, 1973
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Marked fertilization failures occurred on sib inbreeding the first generation of cultures from wild Crassostrea virginica, the commercial American oyster. There was a very significant reduction in the number of eggs undergoing normal cleavage. Penetration of the sibling sperm was often delayed. Frequently fertilization when it did occur was ineffective. Prolonged attempts at fertilization led to increased polyspermy. Parthenogenetic activation of the eggs occurred in the sib crosses with a greater frequency than in crosses of the founding wild stock, or in control outcrosses. Survival and growth rate of the outbred larvae were significantly better than of the inbreds. This is interpreted as indicating that, at least in some indivi-duals in some wild populations of C. virginica, the natural outbreeding nature of this oyster must be reinforced by a system of gamete cross incompatibility with a genetic basis. While gamete cross incompatibility is known to exist in thousands of higher plants, the only carefully documented case in the literature for the animal kingdom is for the ascidians, like the oyster, a marine form.
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  • V. On the Cytology of Hoplobrachium asperipenne Fairm. (Tenebrionidae: Amarygminae), Epilachna septima Dieke (Coccinellidae: Epilachninae), and Caryedon gonagra (Fabr.)
    R. K. Kacker
    1973 Volume 38 Issue 3 Pages 535-538
    Published: September 25, 1973
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Three species, Hoplobrachium asperipenne, Epilachna septima, Caryedongonagra belonging to the family Tenebrionidae, Coccinellidae, Bruchidae respectively have been cytologically investigated. They show diploid numbers 2n=22, 20, 18 respectively. Hoplobrachium shows an increase from the modal number while the Epilachna and Caryedon are characteristic to their generic karyotypes. The chro-mosomal distribution during meiosis in the three families, has been dealt with.
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  • B. B. Chimphamba
    1973 Volume 38 Issue 3 Pages 539-547
    Published: September 25, 1973
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    The 2 species I. dichotoma and B. chinensis were vegetatively and karyotypically very similar and they hybridized not only to give vigorous, F1 and F2 hybrids, but hybrids where some of the chromosomes showed homology and where the gametes were functional.
    The relatively high basic chromosome number of I. dichotoma and B. chinensis (n=16) and the regular bivalent meiosis suggest that they could represent allo-polyploids of species with n=8, a number which characterises some species in the genus Iris.
    The extensive and complete pairing in some cells in the F1 hybrid I. dichotoma×B. chinensis (assuming all the observed pairing was allosyndetic) suggests that the genomes of the species show considerable homology, so that it is possible that the parental species had a common origin.
    The observed affinity between I. dichotoma and B. chinensis suggests that some taxonomic revision of I. dichotoma is desirable.
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