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Volume 39, Issue 2
Displaying 1-25 of 25 articles from this issue
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Ladislav Kubeš, Karel Jirásek, Radovan Lomský1974 Volume 39 Issue 2 Pages 179-194
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSEndocrine cells in the gastrointestinal tract of the dog have been studied by electron microscopy.
Seven types of endocrine cells were found in the gastric mucosa: the gastrinproducing G cells, serotonin-producing enterochromaffin cells, enterochromaffinlike cells, A-like cells, D cells, D, cells, and X cells.
The enterochromaffin cells may be subdivided into two cell types according to the shape and structure of the secretory granules. Contrary to previous reports, the enterochromaffin-like cells were found to reach the gland lumen. Implications resulting from this observation are discussed. The X cells and D cells have so far been described as one single cell type. According to the present findings, the two cells differ distinctly in several respects and should be regarded as two separate cell types.
The intestinal mucosa was found to contain the enterochromaffin cells, S cells, I cells and L cells. In addition, we observed an heretofore undescribed cell type, the secretory granules of which show a granular structure and a highly osmiophilic core. Since we were unable to find any transitory forms between these cells and established cell types, this cell type may represent a new element in the population of endocrine cells of the gastrointestinal mucosa.View full abstractDownload PDF (7024K) -
J. Stephen1974 Volume 39 Issue 2 Pages 195-207
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe cytology of the endosperm in palmyrah palm (Borassus flabellifer Linn.) was studied. During development of the endosperm, the free nuclear stage is followed by differentiation into peripheral cellular endosperm and the central liquid endosperm. At full maturity, the entire nut cavity is filled by the proliferating cellular endosperm. The endosperm was found to be predominently triploid (3x=54). Cells showing multiples of triploid number of chromosomes such as 6x, 12x, 24x, 48x, 96x etc. also were seen in increasing frequency in the mature endosperm. This endopolyploidy was found to be the result of a type of division comparable to c-mitosis. Highly contracted “chromosome bundles” in triploid number were observed in a few cells. Euploid increase such as 4x, 7x, 9x etc., aneuploidy, multipolar mitosis, multiple bridges at anaphase, persistent bridges at telophase, nuclear polymorphism and amitosis were also observed. The nucleolar number was not in strict correlation with the ploidy status. “Ring-shaped nucleoli” were also constantly seen in mature endosperm.
The frequent occurrence of endopolyploidy, aneuploidy, multipolar mitosis, nuclear polymorphism etc. in the endosperm of Borassu flabellifer and unpublished observations on the endosperm of a number of other plants show similarity to the situation in cancer cells.View full abstractDownload PDF (2258K) -
Gisela Laumann1974 Volume 39 Issue 2 Pages 209-213
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSRoot tips of Vicia faba were irradiated with 500 R. To diminish radiation damage the roots were treated with a 0.005 mol solution of spermine for different periods of time. The roots were exposed to this solution not only before but also after irradiation. Mitotic index and irregularities of the nucleus were used as parameters of radiation damage and of radioprotection. It turned out that an exposure of 75 min (concerning mitotic index) and of 90 min (concerning irregularities of nucleus) attain maximal protection. Damage of nucleus was reduced by about 70% (referring to the whole damage) and mitosis was normalized completely. Even Spermine treatment after irradiation shows a protective effect, although it was less than with pretreatment. Mitosis was normalized to 80% while defects of the nucleus were reduced to about 30%.View full abstractDownload PDF (260K) -
Gordon W. Dewald, Syed M. Jalal1974 Volume 39 Issue 2 Pages 215-223
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSMicrosporogenesis, and fertility as measured by pollen stainability, were studied in 27 little bluestem and 24 big bluestem clones from four native populations over a two year period. Diakinetic analyses in little bluestem revealed a diploid chromosome number of 40, a chiasma frequency of 1.88 per bivalent and a low incidence of univalent and multivalent formations. Big bluestem was characterized by a diploid chromosome number of 60, a chiasma frequency of 1.77 and occasional multivalent associations. The presence of multivalents in these species indicate that they are segmental alloploids with incomplete diploidization.
Predominant chromosome aberrations of microsporogenesis in these species were due to homology differences. These were observed as unoriented univalents at metaphase, lagging chromosomes at anaphase I and II, and micronuclei at dyad and quartet stages. Correlation of frequency of these irregularities among meiotic stages indicate that quartet micronuclei may be used as an index of aberration levels arising from homology differences.
Correlation coefficients between meiotic chromosome aberrations and pollen stainability were generally negative and non-significant. Apparently, these aberrations are not solely responsible for the sterility levels in these species.
Other forms of chromosome aberrations encountered, but too infrequent to be treated statistically were, inversion bridges at anaphase I and II, translocation rings at metaphase I and forms of physiological chromosome anomalies.View full abstractDownload PDF (1508K) -
Usha Zutshi, B. L. Kaul1974 Volume 39 Issue 2 Pages 225-232
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSDetailed meiotic studies were carried out on seven species of the genus Solanum, of non-tuberous group introduced from Japan. Five of this species were tetraploid (2n=48) and the other two were hexaploids (2n=72). Among the tetraploid species S. luteum Mill. sub-sp. villosum showed regular meiosis, while sub-sp. alaum showed formation of quadrivalents, trivalents, bivalents and univalents at diakinesis. A large frequency of abnormalities was also observed at anaphase. Solanum ottonis Hylander, another tetraploid species showed presence of 2-3 extra chromosomes. These accessories did not pair either between themselves or with other chromosomes of the complement. Pairing was perfect between the other chromosomes. At anaphase a high frequency of abnormalities was observed. S. melanocerasum Willd. and S. sisymbrifolium Lam., the two hexaploid species showed irregular meiosis with the presence of a high frequency of quadrivalents, trivalents, and univalents besides bivalents. Higher configurations like hexavalents were conspicously absent.View full abstractDownload PDF (375K) -
Pachytene Analysis in an Interspecific Hybrid Oryza punctata Kotschy ex Steud×O. eichingeri A. PeterN. Ranganadhacharyulu, A. Yesoda Raj1974 Volume 39 Issue 2 Pages 233-243
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe hybridization between Oryza punctata and O. eichingeri resulted in completely sterile plants.
At pachytene, bivalent formation mostly between 2 out of 12 chromosomes in the complement was noticed, though a maximum of seven bivalents were observed rarely. The bivalents exhibited intercalary differential segments and asynaptic ends. The karyomorphological differences, with regard to absolute length, arm ratio and centromere position exhibited by the two chromosome complements were negligible.
At diplotene, diakinesis and metaphase I stages also, pairing was observed mostly between two chromosomes, though there were variations from complete univalent formation to the association of 7 bivalents. Rarely trivalent and tetravalent associations were observed. At anaphase I and telophase I abnormalities observed accounted for about 85% and in anaphase II and telophase II, it was about 25%.
From the above observations, it has been concluded that the two species, O. punctata and O. eichingeri might fall within BB, CC and DD genomes of the section Officinalis, both are homologous and are having many karyomorphological similarities.View full abstractDownload PDF (1876K) -
Sumitra Sen1974 Volume 39 Issue 2 Pages 245-251
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe nature and behaviour of B chromosomes in Allium stracheyii and Urginea indica have been studied in detail. In A. stracheyii, a correlated analysis of their behaviour in root cells, pollen mother cells and pollen grains has been carried out. The presence of defective but functioning centromere has been suggested. The heterochromatic constitution of the Bs has been demonstrated. It has been shown that there is no selection barrier for the Bs to enter into the germinal line, though in the pollen grains, over and below a threshold, the B chromosomes are not favoured.
The selective value of B chromosomes is exhibited by their presence in every individual of the population. As in A. stracheyii, in the U. indica as well, tetraploids are devoid of B chromosomes indicating that the adaptability conferred by Bs is not needed in tetraploids with increased tolerance range. The origin of B chromosomes has been suggested through elimination of euchromatic segments from triploids or aneuploids.View full abstractDownload PDF (826K) -
T. Kamala1974 Volume 39 Issue 2 Pages 253-255
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe cytology of a tetrasomic B. campestris (2n=20+2) located in the progeny of autotriploid B. campestris (3n=30) is described. The chromosome involved in tetrasomy is identified at midpachytene as chromosome 8 which is also the nucleolus organising chromosome with subterminal centromere. This forms type A2 in the complement of B. campestris (2n=20) (Venkateswarlu and Kamala 1971). The maximum type of chromosome association observed at diakinesis is a trivalent of the 8th and the 9th types.
Chromosome disjunction at anaphase I and II is more or less regular and meiosis is normal.View full abstractDownload PDF (498K) -
Elsa B. Schuchner, Juan C. Stockert1974 Volume 39 Issue 2 Pages 257-264
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe follicular cells of the corona radiata surround the rat oocyte from the stage of growing follicle. They are arranged as a discontinuous layer, leaving some empty spaces. About 10-12 hours after ovulation, the cells of the corona radiata begin a rapid process of involution showing the disappearance of the cytoplasmic projections as well as ultrastructural alteration of the organelles. By the end of the first day of tubal life, signs of severe damage are evident in the few remaining cells.View full abstractDownload PDF (2742K) -
R. Sethupathi Ramalingam, V. S. Raman1974 Volume 39 Issue 2 Pages 265-274
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe cytogenetics of four interspecific hybrids of Sorghum viz., i) S. subglabrescens×S. sudanense and S. dochna×S. sudanense (Saliva×Spontanea), ii) S. subglabrescens×S. halepense (Saliva×Halepensea) and iii) S. sudanense×S. halepense (Spontanea×Halepensea) were studied for their meiotic and breeding behaviour. The hybrids differed in the degree of expression of heterosis in respect of the characters studied. The lack of abnormalities at diakinesis and later stages of meiosis revealed the genomic homology of the species involved, though the lesser frequency of chiasmata noticed in the hybrids indicated structural differentiation. The wide range in pollen fertility and independence in the extent of seed sterility observed in the F1 and F2 could be conditioned by diplontic sterility factors besides cryptic structural differences. The reduction in chiasma frequency in the hybrids was found to be not associated with the extent of pollen sterility or the degree of morphological differentiation of the parental species. A comparative analysis of the F2 indicated that the degree of recombination was found to be greater in hybrids of Sativa×Spontanea than those of Sativa×Helepensea and Spontanea×Halepensea.
The choice of S. halepense for interspecific hybridisation in breeding projects has been mainly from the point of view of infusing hardiness in the cultivated species. The high degree of morphological differentiation from the cultivated species, and the complex genetic basis of the individual characteristics in which it differs from the latter species are the main factors to be reckoned with, in a breeding project. Though the homology of the genomes may permit gene exchange to a great extent, the control of the spectrum of recombination that is released is rendered difficult, in view of the restrictions imposed by the nature of the genetic factors involved.View full abstractDownload PDF (1972K) -
N. K. Bhattacharyya1974 Volume 39 Issue 2 Pages 275-282
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSTwo oil-yielding varieties of Hesperis matronalis L. of Cruciferae have been cytologically studied. Their chromosome numbers are-1) Hesperis matronalis L. var. I 2n=14; 2) H. matronalis L. var. II 2n=24. Detailed karyotype analysis in the two varieties shows much difference in the structure of their chromosomes. Meiosis has been worked out in both the varieties, which is mostly regular in one and irregular in the other. On the basis of cytological data and marked phenotypic differences, separation of the two varieties as two distinct species has been suggested.View full abstractDownload PDF (922K) -
Yoshio Watanabe1974 Volume 39 Issue 2 Pages 283-288
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSA pentaploid rice plant designated A4 by Nishi and Mitsuoka (1969) showed chromosome-mosaicism in MI of PMCs. When reckoned 2n numbers from the meiotic chromosome configurations, various aneuploid cells ranging from 33 to 99 were observed in one and the same anther-locule.
Morphologically it resembles tetraploid, but anthesis is quite different. As it is similar to cleistogamy, fertilization has never taken place, resulting in the parthenocarpy. When crossed with the pollens of normal diploids, it set only imperfect seeds having no germinating ability. This plant was characterized by the formation of multi-germ-pores on the pollen grain.View full abstractDownload PDF (1081K) -
R. Molina1974 Volume 39 Issue 2 Pages 289-293
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSTreatment of metaphase cells isolated from BHK 21 cell cultures with hyaluronidase is followed by the appearance of a spiral structure in their chromosomes. In many chromosomes, the chromatid consists of two half-chromatids plectonemically coiled.View full abstractDownload PDF (1020K) -
John F. Duncan, Ratna Irsiana, Anni Chang1974 Volume 39 Issue 2 Pages 295-302
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSKaryotypes of the following taxa are described: Rattus bartelsii, Rattus niviventer temmincki, Rattus niviventer treubii, Rattus cremoriventer cretaceiventer, and Rattus fulvescens lepturus.View full abstractDownload PDF (1625K) -
Y. S. R. K. Sarma, S. B. Singh1974 Volume 39 Issue 2 Pages 303-308
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe effects of gamma-rays on a member of Charophyta viz. Nitella flagelliformis have been studied, subejcting the antheridia to (60CO) gamma-rays treatment (100-500 rads). A study of nuclear division in the spermatogenous filaments of treated antheridia, revealed chromsome fragments both at metaphase and anaphase, formation of rings, anaphase bridges and rarely of micronuclei. A linear increase in the number of cells showing chromosomal aberrations with increase in dose has been observed. It is significant to note that this alga is more sensitive to gammarays in comparison to Eudorina elegans and Euglena gracilis studied by other workers. The cytological effects of gamma-rays observed in the present work are almost identical with those produced by X-rays (100-500 rads) on the same species as reported earlier by Sarma and Khan (1967).View full abstractDownload PDF (693K) -
B. N. Singh1974 Volume 39 Issue 2 Pages 309-314
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe samples of Drosophila ananassae have been collected from Jamsoti and Lowari, two small villages of the Chakia forest, U. P., Ukhara a small town near Durgapur, West Bengal, Port Blair and Kamorta situated in Andaman and Nicobar Islands. The samples from these widely separated localities have shown that the three inversions viz., alpha (subterminal) in II L, delta (terminal) in III L and eta (basal) in III R are widely distributed. The natural populations show marked differentiation in distribution of the chromosomal types. The mean number of heterozygous inversions per individual varies in different populations. The highest value is 1.40 for the Port Blair (Andaman) population and the lowest 0.43 for the Jamsoti (Chakia forest) population.View full abstractDownload PDF (307K) -
Maria Luiza S. Mello, B. de Campos Vidal1974 Volume 39 Issue 2 Pages 315-320
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSInterkaryokinesis chromatin and mitotic chromosomes of the onion root tips stained with toluidine blue display anomalous dispersion of the birefringence with one inflection point at about 520 nm. The largest values of the optical path differences are shown by the metaphase chromosomes which are presumed to be more condensed. Banding associated with intense birefringence was also found in prometaphase chromosomes.
Chromosome proteins and their relationships with the DNA do not change during mitosis as measured by constancy in the wavelength of the light absorption peaks.
The patterns of the anomalous dispersion of the birefringence and of the absorption spectral curves on chromosome regions stretched during the squashing show how the cytophysical findings can tell about changes in the molecular ordering of the chromosome structure.View full abstractDownload PDF (813K) -
Usha Goswami1974 Volume 39 Issue 2 Pages 321-325
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESS1. Camallanus baylisi has a diploid number of 9 and 10 chromosomes in the males and females, respectively.
2. The chromosomes are rod-shaped and undergo the normal course of meiosis. They possess multiple centromeres during mitosis and behave as telocentrics during meiosis.
3. Some of the cells show an unequal pair of chromosomes. This chromosome polymorphism has arisen in the gonads since the germ cells represent both the normal long chromosomes of the pair and the unequal pair.
4. But the developing embryos studied from the uteri of the females, showed embryos with all the cells possessing either the long chromosomes or the unequal chromosomes of the particular chromosome pair. The latter embryos also showed an active rate of cell division.
5. It seems that the natural selection is favouring the heterozygotes during these embryonic divisions.View full abstractDownload PDF (249K) -
V. S. Bhatnagar, M. D. L. Srivastava1974 Volume 39 Issue 2 Pages 327-334
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESS1. The karyotypes of four species of bats have been described, of which two are reported for the first time.
2. A comparison of the somatic chromosomes of Pipistrellus mimus and Pipistrellus sp. shows that they must be different species, in disaccordance to the view of systematists.
3. Pathak's classification of the somatic chromosomes of Pteropus giganteus giganteus has been revised.
4. Scotophilus heathi has 3 pairs of m, 4 pairs of sm and 3 pairs of st and 7 pairs of T chromosomes.
5. In all the bats studied the sex-determining mechanism is of XX/XY type.View full abstractDownload PDF (2453K) -
T. S. Sareen, P. K. Khosla, P. N. Mehra1974 Volume 39 Issue 2 Pages 335-339
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSCytological studies have been carried out in 21 woody species. The chromosome numbers of eighteen species have been presented for the first time. The basic numbers suggested for the three newly investigated genera are Lophopetalum (x=20), Elaeodendron (x=17) and Berchemia (x=12). Polyploidy is frequent in Euonymus but rare or unrecorded in other Celastraceae and Rhamnaceae. The role of aneuploidy is significant in Celastraceae, but it appears to be lacking or meagre in Rhamnaceae which seems to have 12 as its original basic number.View full abstractDownload PDF (574K) -
S. P. Rath, S. N. Patnaik1974 Volume 39 Issue 2 Pages 341-352
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSCytology of 24 species belonging to five genera of the family Cyperaceae could be studied in which chromosome numbers are recorded for the first time in 15 species and different numbers have been discovered in 6 species against the previous reports.
All the 14 species of Fimbristylis Vahl cytologically investigated conformed to a single basic chromosome number of x=5. Of these, 12 species were proved to be diploids (n=5) and 2 species were tetraploids (n=10).
On the other hand the meiotic analysis of 5 species of Cyperus L. (sensu lato) revealed five different haploid numbers such as n=8, 13, 18, 21 and 29.
An wide array of chromosome numbers were found in the family ranging from 2n=10 in Fimbristylis Vahl to more than 200 in Eleocharis R. Br.View full abstractDownload PDF (2659K) -
E. C. Jenkins, Albert D. Janerich, Frances M. Giordano1974 Volume 39 Issue 2 Pages 353-356
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSPrevious studies have shown that the macromethod of culture is superior to the micromethod as indicated by mitotic index. By comparing the mean mitotic indices of 15 macro and 18 microcultures derived from three female and three male normal healthy individuals ranging in age from 19 to 29 years, we have found no significant difference between the two culture systems. However, differences between the two methods were seen to vary as a function of the individual. In some cases, one method appeared to be more optimum than the other while in other cases the situation was reversed. In one individual, no difference at all was observed.View full abstractDownload PDF (182K) -
A. K. Saha, A. R. Khudabaksh1974 Volume 39 Issue 2 Pages 357-366
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSTwo lots of grasshoppers, one controlled and the other treated series, are hypodermically injected with 0.25% NaOH and 0.1% of chalcone in 0.25% NaOH respectively at the rate of 0.02-0.03cc/grasshopper. After 4 and 8 hours, the testes are dissected out in normal saline and fixed in aceto-alcohol (1:3) and lastly preserved in 70% alcohol. The stored tissue is stained permanently following Smith's technique.
Qualitative and quantitative studies have been made on the effect of chalcone on spermatocytic chromsomes of grasshopper. The aberration frequency varies with time in treated series but not in controlled series. The result shows that the chemical is markedly effective in reducing the chromosome aberration after 8 hours' treatment.
The probable mechanism and mode of action of the chemical have been discussed in the light of other phenolic compounds worked out on plant and animal chromosomes. It seems that there might be different pathway of action of the chemical i.e., it might disturb the DNA metabolism of cell or the the oxidationreduction system of cell nucleus but not in the classical way as postulated but in a reverse way.View full abstractDownload PDF (2050K) -
R. S. Utkhede, H. K. Jain1974 Volume 39 Issue 2 Pages 367-371
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSA number of diploid and polyploid species of wheat have been analysed for the sensitivity of their chromosomes to conditions of high temperature. A comparative estimate of deoxyribonucleic acid in the root-tip cells of different species has also been made by the autoradiographic technique. The diploid and hexaploid species differed greatly in temperature sensitivity of their chromosomes. The diploid, tetraploid and hexaploid species contained an increased amount of DNA in that order but the increase was not proportional to the chromosome number in these species. No simple correlation was found to exist between the amount of DNA in the cells of different species and the temperature sensitivity of their chromosomes.View full abstractDownload PDF (258K) -
P. K. Seth, W. P. Kunze1974 Volume 39 Issue 2 Pages 373-378
Published: June 25, 1974
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe centromeric regions of the cattle chromosomes exhibit a variable staining property, if staining procedures, which visualize the constitutive heterochromatin in some other species, are used. These regions are non-fluorescing with the fluorochrome “Hoechst 33258” (a benzimidazol derivative) and remain unstained following the staining methods for C and G-banding. However, using the heat denaturationrenaturation procedures, the centromeric regions are darkly stained. This differential behaviour of the centromeric heterochromatin in Bos taurus suggests that the constitutive heterochromatin is heterogeneous in its staining intensities and thus, its variable staining properties may be due to its complex structure or its compositional heterogeneity.View full abstractDownload PDF (1551K)
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