CYTOLOGIA
Online ISSN : 1348-7019
Print ISSN : 0011-4545
Volume 48 , Issue 2
Showing 1-25 articles out of 25 articles from the selected issue
  • S. P. Bhunya, T. Sultana
    1983 Volume 48 Issue 2 Pages 215-220
    Published: June 25, 1983
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    The present paper pertains to the study of somatic chromosomes of an Indian bird, Megalaima zeylanica caniceps (Franklin) (Capitonidae, Piciformes). The diploid chromosome number has been determined to be 2n=90±, there are 17 pairs of macrochromosomes and 28 pairs of microchromosomes. The Z and W chromosomes have been identified to be the largest metacentric and metacentric chromosome of medium length respectively. In one individual a case of pericentric inversion (from st to m type) has been observed in one of the partners of an autosome pair. The C-banding analysis shows occurrence of centromeric, interstitial and terminal heterochromatin in macrochromosomes.
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  • O. P. Patel, C. B. Singh, R. K. Mishra, V. K. Gour
    1983 Volume 48 Issue 2 Pages 221-230
    Published: June 25, 1983
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    1. Detailed karyotypic analysis of ten varieties of different geographical regions have been carried out.
    2. In the somatic counts all the varieties exhibited the similar chromosome number i. e. 2n=30.
    3. Chromosome type B1 and B2 have consistent appearance in all the varieties analysed.
    4. On the basis of chromosome types and genotypic variation in karyotypes it was concluded that these genotypes (varieties) share a common ancestor in origin and have gone under a series of structural alternations.
    5. Karyotypic analysis revealed that species under study follow a progressive evolutionary path way.
    6. According to the extent of karyotypic asymmetry 3 varieties out of ten can be grouped as primitive ones.
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  • J. D. Chaudhary
    1983 Volume 48 Issue 2 Pages 231-236
    Published: June 25, 1983
    Released: March 19, 2009
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    Cytological studies were made in Oplismenus burmannii (n=9, 8 and 2n=45), O. compositus (n=9, 27, 36) and O. undulatifolius (n=27, 27+2 B's). Pentaploid taxon (2n=45) in O. burmannii and diploid taxon (n=9) in O. compositus are new records. Pentaploid of O. burmannii was found to be an asynaptic taxon and has been discussed as a hybrid between O. burmannii (n=18) and O. compositus (n=27).
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  • K. J. Madhusoodanan, M. A. Nazeer
    1983 Volume 48 Issue 2 Pages 237-244
    Published: June 25, 1983
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Morphological and karyotypical analyses of five species of Amaranthus (sect. Blitopsis) have been undertaken. The species are found to be quite distinct, differing in height, mode of branching, shape as well as size of the leaf, structure of infloresence, nature of bract as well as utricle and mode of dehiscence of ripe utricle. Compared to the wild species, the cultivated ones show advanced characters due to selection. The karyotypes of all the species are very much asymmetric with variation in size as well as in form of chromosome sets. No two species are karyotypically alike. Evidently, the species differentiation in members of the section is caused by chromosome repatterning and in evolution of the species structural alterations of chromosomes are playing a key-role.
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  • N. Dayal, C. Prasad
    1983 Volume 48 Issue 2 Pages 245-252
    Published: June 25, 1983
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    The number and ditribution of chromocentres have been studied in nine varietal populations of radish (Raphanus sativus L.) and their six F1 and two F2 hybrids. The mean number and the distribution of chromocentres in the interphase nuclei were found to be characteristic for a population. The varietal populations differed significantly from each other in this heterochromatin phenotye, indicating different degree of heterochromatinization in them. In the F1 hybrids the number of chromocentres averaged midway between their parents. The population having a narrow range of the distribution of chromocentres showed dominance to those having a wide range of the same. F2 hybrid plants, raised from three F1 families, demonstrated a wider range of distribution for number of chromocentres per nucleus than F1's and parents, though they did not differ significantly from the former in the mean number of chromocentres. It has been concluded that the amount and the distribution of constitutive heterochromatin in radish, as inferred from the chromocentre counts, are under the control of genotypes and regulated polygenically.
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  • Aiko Sakai-Wada
    1983 Volume 48 Issue 2 Pages 253-258
    Published: June 25, 1983
    Released: March 19, 2009
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    Cytochemical studies were made on the kinetochore of chromosomes in the first meiotic metaphase and anaphase of pollen mother cells of Tradescantia reflexa. The kinetochore of T. reflexa is ball- or cup-shaped and about 700 nm in diameter. It seems to contain DNA, RNA and basic proteins judging from the effect of uranyle-EDTA treatment, RNase digestion and PTA-staining. The location of these chemical components were also examined.
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  • S. Haque
    1983 Volume 48 Issue 2 Pages 259-266
    Published: June 25, 1983
    Released: March 19, 2009
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    Chiasma frequency and nucleolar behaviour in four species of Salvia e. g. S. farinacea, S. glutinosa, S. coccinea and S. splendens were studied. Out of four species, S. glutinosa showed the highest chiasmata per bivalent (1.18). S. farinacea and S. glutinosa formed both ring and rod bivalents although the number of ring bivalents were less. S. coccinea and S. splendens formed only rod bivalents. Variation in nucleolar number and behaviour was noted in three species of Salvia, e. g. S. farinacea, S. glutinosa and S. splendens. The number of nucleoli varied from PMC to PMC and also the number of bivalents attached to the nucleolus varied. Various causes of low chiasma frequency as well as variation in the nucleolar number and behaviour were discussed in detail. Studies on chiasma frequency were correlated to recombination and evolution among the four species of Salvia.
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  • S. B. Agrawal, Y. S. R. K. Sarma
    1983 Volume 48 Issue 2 Pages 267-274
    Published: June 25, 1983
    Released: March 19, 2009
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    In the present study the effects of gamma rays and X-rays were seen on the karyology of two species of Oedogonium, O. gunnii Wittr. and O. virceburgense Hirn. (Oedogoniales). Various types of chromosomal aberrations were assessed qualitatively and quantitatively. The percentages of chromosomal aberrations and percentages of nuclear degeneration were found to be directly related with the administered doses of gamma/X-rays. Gamma rays were found more effective than X-rays in bringing about a particular type of effect. O. virceburgense proved to be more resistant than O. gunnii for both the radiations.
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  • P. K. Agarwal
    1983 Volume 48 Issue 2 Pages 275-280
    Published: June 25, 1983
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Detailed karyotype studies in Musa rubra Wall. revealed the presence of 2n=22+B-chromosomes. Karyotype was found to be of symmetrical type and was placed in 3A category of the 12 categories recognized by Stebbins (1971). B-chromosomes were found to occur in roots and pollen mother cells. Possible origin of these chromosomes by breaking up of satellites at secondary constriction regions and further acquisition of centromeric activity by these broken satellites have been suggested.
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  • J. L. Karihaloo, A. K. Koul
    1983 Volume 48 Issue 2 Pages 281-287
    Published: June 25, 1983
    Released: March 19, 2009
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    A desynaptic clone of Sternbergia fischeriana has been recorded from Kashmir. It has a diploid chromosome count of 22, 4 long and 18 medium. Of the 11 pairs 2 are heteromorphic. Male meiosis reveals desynapsis of medium strong type. Preponderance of univalents causes irregularities in chromosome segregation resulting in genetically unbalanced gametes, only a small fraction of which are viable. Desynapsis coupled with structural heterozygosity leads to highly aberrant meiosis and results in total sterility of the clone.
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  • M. G. Jadhav, S. P. Birari, S. S. Mehetre
    1983 Volume 48 Issue 2 Pages 289-292
    Published: June 25, 1983
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    The diploid chromosome number in root tip cells in Iseilema vaginjorum, I. membranaceum and Pseudoiseilema australiansis was found to be 2n=18. The chromosome number in P. australiansis and I. membranaceum are new reports. While the karyotypes in these three species are also reported here for the first time.
    The karyotypic studies in all the three species indicated that majority of the chromosomes had submedium and having very less difference in their total chromatin length. However, the three species are found to be distinct in regards to position of the sat chromosomes. The assymetrical karyotype in all these species indicated that they are in the advancing stage of evolution.
    The idiograms of all the three species indicated that except, the minor differnces in the position of sat pairs, they are very allied to each other and seem to have been originated from common ancestor.
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  • Animesh K. Datta, Amal K. Biswas
    1983 Volume 48 Issue 2 Pages 293-303
    Published: June 25, 1983
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Seeds of Nigella sativa L. were irradiated with 4 Kr, 6 Kr, 8 Kr, 10 Kr, 20 Kr and 30 Kr of X-rays. Frequency of germination and rate of seedling growth have shown dose dependent decreasing trend. LD50 was found to lie between 8 Kr and 10 Kr. Chromosomal abnormalities such as fragments, diplochromosomes, ring configuration, lagging fragments with or without bridges, aneuploid cells having fragment and unequal chromosome length, univalents, multivalents, non-orientation, non-synchronous condensation, multipolarity and stickiness of chromosome were noted in post-irradiated materials. Micronuclei were also studied in interphase cells. It appears that X-rays have induced localised breakage at subterminal regions of chromosomes. Total mitotic anomalies enhanced but the frequency of dividing cells decreased with increase in the radiation doses. It appears that mitotic disturbances have affected physiological processes, Pollen sterility and meiotic anomalies have shown dose dependent increasing tendencies, thus indicating that former is an outcome of the latter.
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  • M. D. Angulo, A. M. Sanchez de Rivera
    1983 Volume 48 Issue 2 Pages 305-312
    Published: June 25, 1983
    Released: March 19, 2009
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    Five taxa of Trifolium subterraneum (DV, STG, SA-1, FR and STO) from different Spanish regions have been karyologically studied, taking into account the evolutionary tendencies of the karyotype. Their diploid number 2n=16 and their karyotypical diversity have been evidenced.
    A comparative study with previously studied Extremaduran ecotypes and Australian cultivars has also been conducted to determine the degree of evolution of the karyotype of the different taxa of T. subterraneum L.
    The haploid number n=8 has been determined for each one of the five taxa studied in this paper.
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  • E. B. Ilgren, E. P. Evans, M. D. Burtenshaw
    1983 Volume 48 Issue 2 Pages 313-322
    Published: June 25, 1983
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Cytological and cytophotometrical analyses have shown that multipolar mitotic figures and multinucleate cells are present within mouse decidua. These are, moreover, found exclusively within the antimesometrially-situated decidua and contain not only excessive amounts of nuclear DNA (>4c) but also numerous sets of chromosomes (>2n). Thus, during the growth of mouse decidua, multinucleation probably results from a multipolar nuclear division without concomitant cytokinesis; polyploidisation becomes consequential upon multinucleation; and regionalisation can influence the origin of the multinucleate, polyploid condition.
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  • VII. Nature of nucleolar chromosome polymorphism in Allium cepa var. viviparum (Metzg.) Alef
    Anima Langer, A. K. Koul
    1983 Volume 48 Issue 2 Pages 323-332
    Published: June 25, 1983
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Numerical polymorphism of nucleolar chromosomes has been recorded among various clones of Allium cepa var. viviparum. Loss of visibility of satellites in some plants is accompanied by proportionate reduction in nucleolar number. In some plants, however, nucleolar organization is not impaired by morphological reduction of satellites. Change in number of satellites and nucleoli is seen to tell upon plant fertility.
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  • W. W. K. Cheung
    1983 Volume 48 Issue 2 Pages 333-342
    Published: June 25, 1983
    Released: March 19, 2009
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  • III. Mitotic effect of water extract of Anastatica hierochuntica L. on Allium cepa
    A. S. Shehab, Z. M. Adam
    1983 Volume 48 Issue 2 Pages 343-348
    Published: June 25, 1983
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    In this investigation the cytological effect of Anastatica hierochuntica L. extract on Allium cepa root meristems was followed. Mitotic index depression occurred after direct and recovery treatments. The total percentage of abnormalities increased with increase of time and concentrations. The abnormalities scored were despiralization, spindle disturbance, stickiness, lagging and bridges.
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  • I. Reversible structural modifications of the endoplasmic reticulum
    Christiane Morisset
    1983 Volume 48 Issue 2 Pages 349-362
    Published: June 25, 1983
    Released: March 19, 2009
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    Impairments of the energetic metabolism affect the ultrastructures of the organelles in roots, during long term anaerobiosis (72h). They were fully reversible upon the return to an aerated medium (15h). Comparison was made after uncoupling oxidative phosphorylation by means of the 2-4 DNP, or after plasmolysis which reduces the oxygen uptake. Germ-free excised tomato roots, cultivated in vitro were used.
    The endoplasmic reticulum saccules which were located in the peripheric cytoplasm of control cells, were reduced during the three experiments, possibly associated with a diminution of the chemical exchanges from one cell to another. Other saccules formed long parallel sheets, their ribosomes remaining numerous. A complex system of vesicles was formed in the perinuclear cytoplasm, specifically induced by anaerobiosis.
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  • H. Sau, A. K. Sharma
    1983 Volume 48 Issue 2 Pages 363-372
    Published: June 25, 1983
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    The present paper deals with a detailed chromosome study of 35 species including cytotypes of the tribe Kerosphaereae of Orchidaceae. There are 17 new reports from Eastern Himalayas and the Khasia hills. On the basis of the chromosome behaviour and karyotype analysis it has been concluded that in the subtribe Coelogyneae, the genus Pholidota is allied to Coelogyne and those two represent homogeneous assemblages. In the subtribe Dendrobeae, the genus Dendrobium is quite homogeneous in which polyploidy and aneuploidy along with chromosome changes have played an important role in evolution. Intraspecific chromosome races are common and a clear case has been demonstrated in D. chrysanthum where such cytotypes are correlated with distinct environmental conditions. Dressler (1961) described the northern epiphytes of Mexico and also recorded the severe frost-damage in them excepting Epidendrum conopseum R. Br. (Dressler 1964). In the subtribe Sarcanthineae, the affinity of Aerides with Sarcachilus has been revealed and presence of supernumerary constriction indicates the extent to which structural changes of chromosomes are operating in evolution. The cytological affinity of Stauropsis with Vanda has been shown. The position of the species Hexisea reflexa, newly recorded here from India, has been assigned under Sarcanthineae. In Vanda, polyploidy and aneuploidy occurring at intra and interspecific level as well as cryptic structural alterations have been considered to be the factors which have contributed to the wide geographical distribution and adaptation of the genus. In general, genera cannot be categorised on the basis of their karyotypes. In broad features of the karyotype, the family as a whole represents a normal grouping, as karyotype alterations, though playing a role in evolution, are equally effective at an intra and interspecific level. An illustrated work was published on Orchid pollination and evolution (Dodson 1961).
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  • V. Laxmi, M. N. Gupta, Subodh Kumar Datta
    1983 Volume 48 Issue 2 Pages 373-378
    Published: June 25, 1983
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    A green seed coat colour mutant induced by 0.06% MMS and its parental strain were studied during present investigation. The mutant differed from the control not only in seed coat colour but also in some cytomorphological, palynological and biochemical characters. The mutant was superior to the control in herbage, seed and crude oil yield. The induced mutant seems to be originated due to gene mutation.
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  • R. Sai Kumar, U. P. Singh, R. B. Singh, R. M. Singh
    1983 Volume 48 Issue 2 Pages 379-387
    Published: June 25, 1983
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Aneuploids with 27- to 30-chromosomes were isolated in the progenies of induced tetraploids of pearl millet in a lower frequency in C2 generation. These aneuploids were apparently recovered through female transmission, which varied for aneuploid gametes with different chromosome numbers. Aneuploids could be distinguished from eu-tetraploids on a morphological basis. Cytological study showed that 27-chromosomes variant was characterized by a high frequency of univalents and their precocious splitting at AI followed by the formation of bivalents in addition to rare presence of trivalents and quadrivalents/cell. But bivalents were highly frequent in both hypertetraploids. Thus, a frequency of bivalent is suggestive of “preferential pairing”. Moreover, the induced bivalentization noted in both euand aneuploids of advanced generation tetraploids of pearl millet may be accounted to high selection pressure.
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  • Kumkum Prabhakar, M. R. Vijayaraghavan
    1983 Volume 48 Issue 2 Pages 389-402
    Published: June 25, 1983
    Released: March 19, 2009
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    In Alyssum maritimum the zygote divides to form two cells namely the terminal cell and the basal cell. The basal cell, of the two-celled proembryo, stains less for proteins and RNA than the terminal cell. The derivatives of the basal cell form the suspensor cells of the proembryo and differ histochemically from the organogenetic part of the embryo derived from the terminal cell. The uppermost cell of the suspenson, towards the micropylar end, has been designated as `vesicular cell'. Electron microscopic investigations reveal the presence of wall ingrowths in the vesicular cell which acts as a transfer cell. All the suspensor cells of the embryo are interconnected through plasmodesmata. It is envisaged that the uppermost suspensor cell-vesicular cell-is responsible for the absorption and translocation of the metabolites in micropylar region of the embryo sac. The cell's position in the embryo sac and the peculiar morphology as revealed by EM studies are important adjuncts which enable this cell to mobilise the solutes towards the developing embryo.
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  • Y. K. Bansal, S. Sen
    1983 Volume 48 Issue 2 Pages 403-405
    Published: June 25, 1983
    Released: March 19, 2009
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    In the differentiated tissue of root cells of Hordeum vulgare 2, 4-d induces division. Multi-stranded nature of the chromosomes has been recorded in this zone. The endomitotic replication of chromoomes seems to play an important role in cell differentiation in H. vulgare.
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  • Sumita Jha, Sumitra Sen
    1983 Volume 48 Issue 2 Pages 407-418
    Published: June 25, 1983
    Released: March 19, 2009
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    The present investigation deals with chromosome study of ten polyploid populations of Urginea indica Kunth representing triploids, tetraploids and hitherto unrecorded hexaploid. Different cytotypes frequently occur in the same climatic zone, but the constancy of the karyotype within the populations indicates certain adaptability to the microenvironmental condition to which they are subjected. The karyotype is highly asymmetrical both in size and morphology. There is no reduction in chromosome size along with polyploidy. The populations, however, differ with respect to minute karyotypic details. The role of structural alteration of chromosomes in the evolution of races is evident. Occurrence of large number of cytotypes both numerically and structurally altered as well as extensive vegetative reproduction has resulted in wide distribution of U. indica.
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  • Susumu Toyama
    1983 Volume 48 Issue 2 Pages 419-426
    Published: June 25, 1983
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Super-fine structure of the envelope membranes of spinach chloroplasts was observed with ultrathin sections fixed in glutaraldehyde and osmic acid. Both inner and outer membranes are not composed of unit membranes, but of a number of fine grains which are 13 to 16Å in diameter and 14 to 16/100nm2 in density and of a matrix between them. The grains do not appear to be regular in distribution. The outer membrane of the envelope is different from the inner membrane in both electron density and thickness, that is, the former is less dense and 60 to 70 A thick, and latter is dense and 75 to 85Å thick, Both membranes are separated by a electron transparent zone of 40 to 60Å in width.
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