CYTOLOGIA
Online ISSN : 1348-7019
Print ISSN : 0011-4545
Volume 53 , Issue 3
Showing 1-25 articles out of 25 articles from the selected issue
  • III. Concluding remarks
    Ajay K. Jain, R. K. Sarbhoy
    1988 Volume 53 Issue 3 Pages 427-436
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Cytogenetic effects of Benzene hexachloride (BHC), Lindane, Aldrin, Heptachlor and Endrin on Lens culinaris, L. esculenta, Pisum sativum and P. arvense were studied through roottip, seed-soak and spray treatments. The probable mechanisms responsible for various type of chromosomal abnormalities and phenotypic alterations due to the treatment of these pesticides have been discussed in detail. Effects of these pesticides did not appear to be heritable in successive generation. But it is difficult to say that these chemicals are entirely safe from genotoxicity point of view. The appearance of multivalents and chromatin bridges suggests that these chemicals can affect genetic recombinations, which may lead to the loss of important factors or gain undesirable characters. The routine cytogenetic screening of standing crops may be one of the helping tool in maintaining the purity of germ plasm. Among all 5 screened chemicals BHC appeared to be most potent genotoxic agent and suggests to have more detailed mutagenic screening in other test systems also.
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  • Oli Sen, Sima Bhattacharya
    1988 Volume 53 Issue 3 Pages 437-440
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Cytogenetical studies in Vigna glaberscens TTK1 revealed twenty two and fourty four as haploid and diploid chromosome numbers respectively. Spontaneous occurrence of cytomixis is due to the transfer of chromatin material from one pollen mother cell to other through connecting channel has been noted. Pollen mother cells with reduced chromosome number (n=6, n=7) higher than the modal number (n=22) have also been recorded. Grouping of bivalents and late separating chromosomes were some of the noted abnormalities.
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  • Anadi Kumar Kundu, A. K. Sharma
    1988 Volume 53 Issue 3 Pages 441-445
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Chromosome study has been carried out on seven species belonging to six genera of the family Lamiaceae, with the aid of improved techniques. The general feature noted in this family is the wide range of chromosome numbers with graded symmetrical karyotypes. All the chromosomes are very small and are submetacentric to nearly submetacentric in nature. The species differ from one another in minute karyotypic details and in number of chromosomes with secondary constrictions.
    Both numerical and structural alterations in chromosomes have been operative in the evolution of the different members of this family.
    A monophyletic origin of the different members from a common deep seated base number has been indicated. The tree habit observed in this family has been regarded as a “sport” not contributing to any further evolutionary progress.
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  • M. Ashraf, M. B. E. Godward
    1988 Volume 53 Issue 3 Pages 447-456
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    The ultrasturcture of telophase has been followed in a green alga, Spirogyra submargaritata. A series of transitional changes of dark fibrillar material, appearance of nucleoplasm and chromocentres have been demonstrated. It has been shown that the pale fibrillar material extending from the decondensing chromatid of telophase is identical in appearance with the “Pale fibrillar centres” described in sectioned nucleoli by numerous authors. It is contented that these observations taken together constitute evidence that the pale fibrillar material of the nucleolus is the chromatin of the nucleolar organising regions of the chromosome which apparently are actively involved in the synthesis of new nucleolar material (rRNA), and that in reorganisation of the new nucleolus at telophase.
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  • Maitreyi Banerji, Amiyanshu Chatterjee
    1988 Volume 53 Issue 3 Pages 457-463
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Callus cells of Vicia faba L. were irradiated with gamma-ray upto 8 kR and their effect on calli, immediately after irradiation and during recovery was investigated. Study was done on growth, cytology, morphology and rhizogenetic behaviour of calli. Recovery was possible till 4 kR and while the effect in all the cases seems to be dose dependent the recovery appears to be independent of dosages upto a limit of 4 kR. No significant difference was observed among regenerated roots. Change in structure of chromosome was observed in older calli.
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  • D. S. Tripathi, S. K. Roy
    1988 Volume 53 Issue 3 Pages 465-468
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    MIC polluted two year stored soil sample from Bhopal were tried for supporting onion bulb growth. Observations revealed retardation of root growth due to induced cytological anomaly in their cells. The poor growth of roots and more chromosomal aberrations in the previous sample than in the latter show that the MIC worked as a retardant or inhibitor. The decrease of percent chromosomal aberrations and improvement of root growth in latter soil sample suggests lowering of the level of soil pollution caused by toxic methylisocyanate gas during leak at Bhopal.
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  • Anadi Kumar Kundu, A. K. Sharma
    1988 Volume 53 Issue 3 Pages 469-474
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Cytomixis has been observed in the pollen mother cells of Leucas aspera, two species of Mentha and two populations of Leonurus sibiricus. In Mentha piperita L. (2n=120), it has been noted to be of common occurrence as it occurs in almost all the stages of meiotic division. The probable correlation between the aneuploid gamete production, pollen sterility and the cytomictic connections in all the investigated taxa has been indicated.
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  • Dilip De Sarker, Kalyan B. Datta
    1988 Volume 53 Issue 3 Pages 475-483
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Cytogenetic analyses have been carried out to elucidate the mechanism of sex expression in T. anguina cv ‘Long Green’, and in sex forms of cultivated and wild T. dioica.
    A uniform number of 22 chromosomes has been recorded in the somatic complements of all the taxa investigated. Three or more pairs of chromosomes with secondary constrictions have been recorded in the taxa investigated. Androecious representative of T. dioica cv ‘Kalyani’ is characterized by the presence of a heteromorphic pair. A similar heteromorphic pair is represented not only in the androecious form of wild T. dioica but also in T. anguina. A heteropycnotic chromatin body in some interphase cells of somatic tissues has been observed in the androecious members of both wild and cultivated T. dioica.
    The gametic number of eleven chromosomes is uniformly represented in all the taxa studied. Regular bivalent formation is noted in most of the male meiocytes analysed. Structural and functional heterogeneity are reflected in the occurrence of a heteromorphic bivalent and in the asynchrony of first anaphasic separation in the androecious members of both wild and cultivated T. dioica.
    Giemsa C-banding studies have been carried out in T. anguina cv ‘Long Green’ and two sexes of T. dioca cv ‘Kalyani’. The banded karyotypes of somatic complements are characterized by distinct telomeric bands. The gynoecious form of T. dioica shows diffuse banding in a pair of chromosomes, while the androecious sex is characterized by one member of the pair without any band. Such chromosomes are completely absent in T. anguina.
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  • O. P. Chaurasia, S. P. Sinha
    1988 Volume 53 Issue 3 Pages 485-489
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Single super phosphate when administered at the rate of 500 mg per mice per day for a total period of seven days, induced a six-fold increase in the rate of chromosomal abnormalities in their bone marrow cells. Gross type abnormalities like pulverisation, stickiness, clumping etc. and individual ones like breaks, centric fusions, deletions were observed. The breaks were non-random and more frequent in the distal region of chromatid.
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  • T. V. V. Seetharami Reddi, D. Rama Mohana Rao
    1988 Volume 53 Issue 3 Pages 491-498
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Seeds of rice cultivars Jaya, IET 5656 and Fujiminori were presoaked for 24 hours and then (a) irradiated with 4, 6, 8, 10 and 12 KR gamma rays, (b) treated with 0.001, 0.002, 0.004 and 0.005 molar solutions of sodium azide at pH 3 for 4 hours, or (c) subjected to combinations of the above with the view to study their relative effectiveness and efficiency in inducing chlorophyll mutations in rice. In all three varieties azide treated entries showed a higher frequency of chlorophyll mutants than did the gamma ray treated entries, under both single and combination treatments. In the variety Jaya sodium azide treatments showed a higher efficiency and effectiveness than gamma rays and combination treatments and they were more or less similar in both single and combination treatments in the other two varieties. The indica cultivars Jaya and IET 5656 were more sensitive than the japonica cultivar, Fujiminori to producing chlorophyll mutations. Sodium azide appears to be more efficient than gamma rays alone or in combination.
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  • S. E. Schlarbaum, L. B. Johnson, D. L. Stuteville
    1988 Volume 53 Issue 3 Pages 499-507
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Somatic chromosome studies using acetocarmine and various banding procedures were initiated on plants of Medicago sativa (2n=4x=32), alfalfa. Banding methodologies were not superior to a conventional acetocarmine staining procedure in specific chromosome identification. A karyotype analysis was conducted on the acetocarmine-stained chromosomes of a plant (RS-K2) selected from the Regen-S cultivar. Chromosomes were divided into eight groups according to the tetraploid nature of M. sativa. Sixteen chromosomes had metacentric centromeres, with the remaining chromosomes appearing more submetacentric. Four SAT-chromosomes were detected, and chromosomes of one group exhibited tertiary constrictions. Certain chromosome groups were indistinguishable because of similar lengths and arm ratios. A generalized chromosome classification system was developed to aid in identification of specific changes in chromosome structure and number. Comparison of the karyotypes of the donor plant with a regenerated protoclone using the chromosome classification system indicated that translocations and chromosome loss occurred in specific chromosome groups.
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  • A. Geneix, P. Malet, P. Bonton, B. Perissel
    1988 Volume 53 Issue 3 Pages 509-515
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Les auteurs presentent l'état actuel des recherches et applications pratiques de l'analyse automatique du caryotype humain. Ils décrivent en particulier le système mis au point à Clermont Ferrand.
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  • U. C. Lavania
    1988 Volume 53 Issue 3 Pages 517-524
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    The details of chromosome morphology in 16 plant types belonging to 11 different species and chemocytotypes of Cymbopogon are presented for the sake of karyological assessment and chromosome identification. In general, the karyotypes are nearly symmetrical with median to submedian centromeres. The range of total chromatin length (haploid complement) varies from 17.46μm to 28.7μm in diploids (2n=20), 38.9μm to 42.7μm in 2n=40 types and 81.75μm in 2n=60 type; and the individual chromosome length between 1.2μm to 5.65μm. The occurrence of polyploid series within C. flexuosus as reported by earlier authors seems to be an illusion due to ambiguity in identification. The assessment of karyological data reveal that repatterning of the karyotype, tandom variation and allopatric polyploidisation might have played an important role in speciation in the genus.
    The organisation of chromatin and centromere seem to be in transitory stage of specialisation consummated through differential chromosome condensation and centromere localisation. Such an endowment is likely to generate instant chromosomal instability due to reduced kinetochore activity to some extent. so commonly encountered in the various species of this genus.
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  • I. D. Arya, S. Rama Rao, S. N. Raina
    1988 Volume 53 Issue 3 Pages 525-534
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Induction of autotetraploidy has been achieved in Trigonella foenum-graecum (2n=16) by cotton-swab method using 0.15% colchicine. The synthesized colchiploids (C0) were maintained for three successive generations (C1, C2, C3). Detailed morphocytological analysis has been carried out in each generation. A distinct enhancement in different vegetative parts was observed in the autotetraploids making them economically more useful. The 5 seeds collected in C0 generation were multiplied and as many as 200 seeds were collected in C3 generation.
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  • S. Ignacimuthu, C. R. Babu
    1988 Volume 53 Issue 3 Pages 535-541
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    The 2C amounts of DNA for Vigna sublobata (Roxb.) Babu and Sharma (the wild relative), V. radiada (L.) Wilczek cv. PS 16 (cultivar) and V. mungo (L.) Hepper cv. T 9 (cultivar) and their M1 generation plants were determined by cytophotometric and UV spectrophotometric methods. The RNA content was determined by UV spectrophotometric methods. The range of variation of DNA per cell as determined by cytophotometry was 3.11-3.61 pg; by UV spectrophotometry it ranged from 3.77 to 4.47 pg. The RNA amount ranged from 14.00 to 17.23 pg. The wild relative showed lower DNA and RNA values. Nuclear volume was lower in the wild relative than the cultigens. These results indicate that the evolution is towards an increase in nuclear volume, 2C DNA and RNA values. Deletions and translocations seem to have played a great role in genome evolution.
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  • III. Interpopulation differences in the karyotypes of 3 species of Astragalus L
    Mohmad Ashraf, R. N. Gohil
    1988 Volume 53 Issue 3 Pages 543-549
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Three species of Astragalus, namely A. grahamianus, A. leucocephalus and A. zanskarensis, collected from two geographically isolated locations each, have been found to exhibit inter-population karyotypic differences. These populations have been found to differ from each other in almost all the karyotypic features like the range of chromosome size, types of chromosomes constituting their karyotypes, total chromatin length, mean chromatin length and the position of marker chromosomes in their idiograms. These interpopulation karyotypic differences and their bearing on the evolution, in these species, have been discussed.
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  • D. J. Coates, D. E. Yen, P. M. Gaffey
    1988 Volume 53 Issue 3 Pages 551-560
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Further cytological study of Colocasia taro in the Pacific utilizing karyotypic data has produced a hypothesis for two separate lineages of the plant within contemporary populations. This provides support for domestication in the western Pacific independent of diffusion of Asian cultigen forms, but it is indicated that confirmation awaits more comprehensive karyotyping of Indian and Southeast Asian material.
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  • M. K. Khosla
    1988 Volume 53 Issue 3 Pages 561-570
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    F2 populations were raised from the partial fertile F1 hybrid of O. gratissimum×O. viride and their reciprocal hybrids which showed a great diversity from extra ordinary gigantic plants to highly dimnitive ones. F2 segregants were grouped into six categories having chromosome numbers 2n=40, 42, 44, 45, 48 and 80 respectively. Six plants (one from each category) with promising combinations of desirable characters have been selected. All the F2 selectants especially plant no. 6 were higher yielders. The F2 selectants exhibited highly irregular meiosis excepting plant no. 6 which showed normal meiosis. Various meiotic irregularities investigated have been discussed. The detailed morphological and cytological studies of F2 segregant have shown that there is hardly any correlation between the phenotypic features and the chromosome number present in these variants.
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  • V. P. Patil, Supriya Gandhi
    1988 Volume 53 Issue 3 Pages 571-575
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Comparative analysis of chiasma frequencies and terminalization in five species of Chlorophytum suggested total number of chiasmata per PMC to be maximum in C. glaucum and minimum in C. laxum possibly due to polyploid nature of the species.
    Close correspondence of mean number of chiasmata per bivalent and mean bivalent length per unit chiasma suggested least linear differentiation as observed in C. laxum and C. tuberosum. Reverse situation observed in C. glaucum indicated non-random distribution or stationary chiasmata with relatively more linear differentiation. This has been further confirmed from the stationary interstitial chiasmata at both diplotene/diakinesis and metaphase I stages.
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  • R. N. Singh, S. K. Roy
    1988 Volume 53 Issue 3 Pages 577-584
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    An autotetraploid was raised as a result of colchicine treatment in Petunia hybrida Hort. to enhance the ornamental value. Treated plants were showing gigantism in comparison to their diploids and also improvement in flower parts through colchiploidy breeding. Moreover, the tetraploid flowers stayed longer resulting in an improvement in keeping quality and extension of blooming period to some extent. Detailed cytological observations made during the present study have shown the occurrence of multiple association of chromosomes which often lead to meiotic irregularities in the induced tetraploids. Yet, abnormalities appeared due to the effect of colchicine, the consequences of these being increased pollen sterility which lowered plant fertility. The gigas characters of C1 also tended to lessen in C2 generation but more in comparison to their diploid plants.
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  • V. Padmaja, P. Sudhakar, A. Ramakrishna
    1988 Volume 53 Issue 3 Pages 585-589
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Cytogenetical investigations on a spontaneous male sterile mutant isolated from the inbred lines of white flowered variety of Petunia axillaris (Lam.) B.S.P., revealed a digenic pattern of inheritance of the mutant character. The original mutant as well as those obtained subsequently in F2 and F3 generations showed unimpaired female fertility and resembled in morphology the male fertile sibs, except for the small, shrivelled empty anthers.
    Microsporogenesis in the sterile paints was apparently normal upto the liberation of microspores from the tetrads, which degenerated subsequently resulting in complete absence of pollen grains in the anthers. In addition, male sterility was found to be invariably associated with atypical behaviour of tapetum, characterised by prolonged nuclear divisions and untimely degeneration as a result of conversion from glandular to periplasmodial type.
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  • Sm. P. Muthu
    1988 Volume 53 Issue 3 Pages 591-599
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    1. The chromosomes of 20 males each from the population of 1985-'86 and 1986-'87 of a tettigoniid, Elimaea securigera, have been examined. The population showed chromosomal polymorphism in the diploid numbers and in the karyotypes.
    2. The normal number is 2n (_??_)=24 AA+X and the karyotype includes two metacentric autosomes. In two of the twenty males of'85-'86 and seven of the twenty males of'86-'87, the number has increased to 2n (_??_)=25 AA+X; one of the metacentrics has dissociated into two acrocentrics.
    3. The presence of supernumeraries in the population indicates the possibility of one of them being the ‘donor’ chromosome in dissociation.
    4. The formation of the acrocentrics by dissociation, and not by centric fission, is explained. Only dissociation can result in acrocentrics; fission will produce telocentrics. The derivatives of the metacentric in E. securigera are acrocentric: the short arm beyond the centromere in one of these chromosomes proves this; the increase in the lengths of the acrocentrics, derived from the metacentric, also points to dissociation as the mechanism for their origin; centric fission cannot be the mechanism.
    5. The work provides the critical evidence for the dissociation hypothesis of M. J. D. White; the hypothesis has been challenged for want of such evidence.
    6. The evolution of a new karyotype and the probability of further evolution are discussed.
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  • N. Jayabalan, G. R. Rao
    1988 Volume 53 Issue 3 Pages 601-605
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Cytological effect of single and combination treatments of gamma rays, EMS (ethyl methane sulfonate) and NMU (nitrosomethyl urea) was studied in two cultivars of Lycopersicon esculentum Mill., namely CO. 2 (Coimbatore. 2) and PR (Pusa Ruby). A number of meiotic abnormalities were observed. They included stickiness of chromosomes, univalents, multivalents, unoriented chromosomes, bridges, laggards and micronuclei. In general meiotic abnormalities and pollen sterility were more in combination treatments than the single treatments. Combination treatment of gamma rays and NMU showed more sterility. CO. 2 showed a greater sensitivity as compared to PR in the combination treatments.
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  • Syôiti Satô, Naoko Yamada
    1988 Volume 53 Issue 3 Pages 607-615
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Scanning electron microscopic observation on the interaction between stigmata and pollen grains, in cross- and self-pollinated cultivars of Primula sieboldii E. Morren, has been examined. This species and its cultivars have generally a heterostylic character, namely pin form and thrum form, of which pollination have a relation to the length of stigmatic papillae and the size of pollen grains. Pollen grains on the cross-pollinated stigmata, germinated and their tubes grew and later penetrated into the stigmata, therefore the fertilization was carried out successfully. In the self-pollinated stigmata, on which pollen grains germinated and abnormally grew, but almost never penetrated. We suggest that compatibility or incompatibility depends on the genetic control.
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  • Michael Pillay, Ann Marie Thro
    1988 Volume 53 Issue 3 Pages 617-625
    Published: September 25, 1988
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Lotononis bainesii Baker, a diploid, and L. angolensis Welwitsch ex Baker, a tetraploid, are self-pollinated, herbaceous perennial legumes native to southern Africa. Because these species are grazing tolerant and have high nutritional quality and palatability, they are under study for summer pasture improvement. Gross morphology of L. bainesii and L. angolensis chromosomes was examined using conventional and C-banding techniques. Ideograms are presented showing that the two species were distinctly different in chromosome morphology and C-banding patterns.
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