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Volume 57, Issue 2
Displaying 1-22 of 22 articles from this issue
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R. W. Masuelli, E. L. Camadro1992 Volume 57 Issue 2 Pages 161-166
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSMeiotic analysis, pairing affinity and fertility studies were carried out in Solanum commersonii Dun. (cmm, 2n=2x=24) by Solanum gourlayi Haw. (grl, 2n=2x=24) triploid hybrids, obtained through the functioning of 2n eggs of cmm. Mean arm pairing frequency (“C”) and relative affinity (“X”) were calculated according to Alonso and Kimber (1981). The “C” value was high but the “X” value was intermediate. Pollen stainability for three triploid hybrids was 31.7, 29.5 and 2.5 respectively. Crosses between the cmm×grl triploids, used as females, and various species of Solanum with different ploidy were performed. Hybrids with 24 to 31 chromosomes were obtained from these crosses. The results of this study give and indication that the cmm and grl genomes are highly homologous. Therefore a high degree of gene exchange between the genomes of these species is expected to occurr in meiosis. The feasibility of utilizing grl as a “bridge” species, for transfering important genes of cmm to the cultivated potato, Solanum tuberosum L. are discussed.View full abstractDownload PDF (1510K) -
R. R. Hegde, S. S. Naik, S. P. Halappanavar1992 Volume 57 Issue 2 Pages 167-172
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSHistochemical localization of total insoluble polysaccharides, RNA and total proteins reveals that differentiating floral organs in isogenic male fertile and cytoplasmic male sterile cv. Anand-119 are rich in RNA and proteins. Carbohydrates are observed in the mature axial cells, and mature sepals and petals. Ontogenetically and histochemically floral apices of both the lines are identical until the differentiation of gynoecium. Subsequent to the differentiation of gynoecium, growth of the stamen primordia ceases in the male sterile line. Stamen primordium fails to differentiate into a filament and anther. The results suggest that homogenous cells of stamen primordium does not disintegrate, but merge with the cells of the gynoecium.View full abstractDownload PDF (1589K) -
Bandla S. Giri1992 Volume 57 Issue 2 Pages 173-179
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSKaryology of thirteen taxa belonging to four genera, Pinnularia, Gyrosigma, Navicula and Gomphonema, was studied. Chromosome numbers determined for different taxa ranged from 2n=6 to 2n=64. Chromosomes were mostly dot-like or rod-like and varied from 0.25 to 1.7μm in size. Metaphase organisation of chromosomes was found to be either plate or ring. Chromosome numbers recorded in the present study are new to science.View full abstractDownload PDF (1551K) -
Junko Miyamoto, Siro Kurita, Gu Zhijian, Li Hen1992 Volume 57 Issue 2 Pages 181-194
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe C-banding patterns of 18 taxa of the genus Pariswere analyzed with the chromosome image analyzing system, CHIAS. Each species examined had a unique and matchless C-banding pattern (Figs. 1, 2). Among them, P. japonica, a presumptive relict to the Ice Age, showed the most complicated pattern and had the highest proportion of C-banding positive heterochromatin to euchromatin in its genomes. P. thibetica, a Tibetan species, showed the simplest pattern and the lowest proportion of heterochromatin to euchromatin. Despite the uniqueness of each species, we were able to recognize certain similarities between and/or among species. The metacentric chromosomes of P. polyphylla var. stenophylla and P. polyphylla var. yunnanesis showed similar banding patterns. Proximal bands were observed on both arms of the metacentric chromosomes in three Japanese species, P. japonica, P. tetraphylla and P. rerticillata. On the other hand, we were unable to make any distinction of the C-banding patterns of “tropical” and the “temperate” karyotypes.View full abstractDownload PDF (1651K) -
H. Akai1992 Volume 57 Issue 2 Pages 195-201
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSUltrastrucutral changes of the epitracheal gland of Bomyx mori were observed electronmicroscopically during the molting cycle. One of the most notable characteristics is that the gland cell contains numerous electron dense droplets in the cytoplasm. These droplets are produced in the cytoplasm during the feeding period, and are degenerated during the molting stage. The degenerated fibrous materials are temporarily stored in variously sized vacuoles in the cytoplasm, and then these materials seem to be released into the hemolymph. From these observations, it is believed that the gland is a sort of endocrine organ functioning in periodic biosynthesis and in the release of the digested materials with each molting cycle.View full abstractDownload PDF (2672K) -
Elisa R. Parodi, Eduardo J. Cáceres1992 Volume 57 Issue 2 Pages 203-208
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSMitosis and cytokinesis in haploid cells of Rhizoclonium hieroglyphicum ssp. hieroglyphicum were studied as the light microscope level.
Nine stages of mitosis were distinguished: interphase, prophase, early and late metaphase, early, middle and late anaphase, and early and late telophase. Cells normally contained two interphasic nuclei. The onset of mitosis was synchronous in all the nuclei of any one cell and was sometimes found to be simultaneous in contiguous cells.
The nuclear envelope disorganized at metaphase; during early metaphase twenty-four (6sm and 18m) homogeneously stained chromsomes formed a very dense circular arrangement.
In anaphase, axis of the spindle usually formed an angle of about 30° with longitudinal axis of the cell. There was no great spindle elongation and the daughter nuclei remained close together. The nuclear membrane reorganized at telophase. Cytokinesis occurred by centripetal growth of a transversal wall.View full abstractDownload PDF (1319K) -
B. V. S. Subrahmanyam, Y. B. K. Chowdary1992 Volume 57 Issue 2 Pages 209-212
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSKaryological investigations on four taxa of Nitella have been carried out. The chromosome counts recorded are all new records to the respective taxa. Chromosome numbers are n=9, 27, 12 and 9 to N. furcata subspa flagellifera f. flagellifera RDW, N. furcata subsp. megacarpa f. megacarpa (T. F. A.) RDW, N. pseudoflabellata var. elegans (Pal) RDW and N. gracilis f. intermedia (Nordst.) RDW, respectively. N. graeilis f. intermedia is karyologically investigated from India for the first time.View full abstractDownload PDF (679K) -
V. R. K. Reddy, M. Annadurai1992 Volume 57 Issue 2 Pages 213-216
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe effect of gamma rays, EMS, sodium azide and their combination on various cytological parameters in M2 generation were studied in lentil variety PL-639. The mean values of quadrivalents, rod bivalents, univalents, fragments/bridges, cytological abnormal cells and pollen sterility were increased in mutagenic treated population, while the chiasma frequency was decreased. Combined treatments showed additive effect, EMS produced slightly more abnormalities over sodium azide. Pollen sterility could be used as a parameter for selection plants having more number of quadrivalents.View full abstractDownload PDF (648K) -
Parimal Kumar Khan, S. P. Sinha1992 Volume 57 Issue 2 Pages 217-221
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSConcurrent administration for seven days of therapeutic (10mg/kg bw/day) as well as 20 and 40mg/kg bw/day doses of vitamin C (L-ascorbic acid) with sub-lethal oral dose of endosulfan to Swiss albino mice could cause significant decrease in the incidence of pesticideinduced chromosomal abnormalities in the bonemarrow cells. This effect was most pronounced at 20mg/kg bw/day dose. The pesticide alone could induce both structural as well as mitosis-disruptive types of chromosomal abnormalities, albeit the latter was not significant. The effective antimutagenic doses of vitamin C, when administered alone, failed to produce any significant genotoxic effect of their own.View full abstractDownload PDF (350K) -
F. Fantana, D. Goldoni, G. Grandi1992 Volume 57 Issue 2 Pages 223-226
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe Ag-pattern of amplified nucleolar material in various stages of R. lucifugus oogenesis has been followed. At zygotene a nucleolar mass is associated with chromosomal nucleolar organizer regions. At pachytene small brown extra nucleoli are interspersed among the bivalents. At early diplotene the microuncleoli fuse into larger nucleoli. During the late stage of oogenesis large masses of silver stainable material (ribonucleoprotein aggregates) are released in the cytoplasm.View full abstractDownload PDF (865K) -
Joseph Jose, John. E. Thoppil, Laly Mathew1992 Volume 57 Issue 2 Pages 227-229
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSKaryomorphological studies in 5 species of Peperomia reveals that P. pellucida H. B. K. is a tetraploid with 2n=44, P. glabella var. variegata is a triploid with 2n=36 and the other three (P. magnoliaefolia A. Dietr., P. polybotrya H. B. K. and P. obtusifolia A. Dietr.) are diploids with 2n=22 chromosomes. The n=11 chromosomes of the tetraploid and diploid species seems to be pronounced and may represent the basic set from which n=12 of the triploid species might have been derived. Species of Peperomia differ in minute details of karyotype suggesting the role of minute structural alterations in speciation.View full abstractDownload PDF (161K) -
Maria Suely Pagliarini, Marli A. dos Santos Pereira1992 Volume 57 Issue 2 Pages 231-235
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSPilocarpus pennatifolius shows a high frequency of fruits with abortive carpels. In order to verify the causes of the undevelopment of these carpels, seven wild specimens were analysed for their meiotic process. Meiotic abnormalities such as irregular chromosome segregation were observed in six specimens. Three specimens showed cytomixis in less than 1% of the analysed cells. This phenomenon was observed from the initial phases of meiosis to telophase I. These irregularities may have contributed, partly at least, to the reduction of pollen viability. However, they cannot justify for themselves the high rate of abortive carpels in this species. It is possible that other factors, not related to meiotic abnormalities, may be affecting the fertilization process.View full abstractDownload PDF (1192K) -
Maria Suely Pagliarini, Marinete Martinez, Irenice Silva1992 Volume 57 Issue 2 Pages 237-240
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSOchna's meiosis has been analysed in search of factors that could cause the abortion of fruits. Results showed low frequency of meiotic irregularities but high frequency of tetrads with a variable number of microcytes, besides converging spindles in meiosis II leading up to the formation of triads. Abnormal behaviour of the nucleolus was also observed in many microsporocytes. These factors may explain, at least in part, the high frequency of abortion in Ochna's fruit.View full abstractDownload PDF (753K) -
G. K. Manna, A. Sadhukhan1992 Volume 57 Issue 2 Pages 241-246
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe sample of the human intestinal parasitic flagellate, Giardia lamblia P1 (P1 Tr1) and the supernatant fluid (Su Tr2) and the precipitate suspended in saline (SSP Tr3) of the centrifuged autoclaved G. lamblia culture were intraperitoneally injected individually to separate sets of mice at the rate of 1ml per 100g body weight against sterile TYI medium (TYI Co1) and nomal saline (Sa Co2) injected controls which yielded maximum cytogenetic effects with respect to bone marrow chromosome aberration frequency, micronucleated erythrocytes and sperm head abnormality tests in supernatant fluid treated sample (Su Tr2) and followed in descending order by the treatment of G. lamblia P1 sample (P1 Tr1) and saline suspended precipitate sample (SSP Tr3). At 24 hr after treatment the net increase in frequency of effect in three different samples of G. lamblia P1 treated series over respective controls was 17.75%, 8.50% and 5.75% respectively for bone marrow chromosome aberration; 0.83%, 0.61% and 0.40% respectively for MNT and 3.15%, 2.00% and 1.10% respectively for sperm head abnormality. Further, the frequency of bone marrow chromsome aberration for the treatment of G. lamblia P1 sample (P1 Tr1) was also found higher by 2.5% at 3 hr and 12.5% on 7 days over control. On 7 days after treatment it was also higher by 0.83% for MNT and 2.85% for sperm head abnormality. Thus the mutagenic potential of different samples of G. lamblia P1 in treated mice was proved by more than one test adding a new evidence to the field of living mutagenesis.View full abstractDownload PDF (1048K) -
B. C. Patil1992 Volume 57 Issue 2 Pages 247-252
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe production of tetraploid plants in Crotalaria linifolia Linn. was attempted with a view to produce more robust plant for fodder. Seed and seedling treatment with different concentrations of colchicine was tried. Seedling treatment proved to be effective.
Size of leaves, flowers, stomata and pollen grains of the tetraploid plants showed enchancement over the diploids. Plant height, raceme length, number of flower per raceme, number of pods, size of pods, seeds per pod were however, lower in tetraploid plants. Pollen fertility in diploid and tetraploid plants was 99.82% and 28.57% respectively.
Meiotic observations showed abnormalities such as, univalents, and trivalents at metaphase I, unequal distribution of various combination, laggards at analphase I, II micronuclei at telophase I, II and at tetrad. These irregularities were the major factors for high sterility of pollen grains in induced tetraploid plant of C. linifolia.
In having larger leaves and bigger seeds, the tetraploids possesses promising economical features. The lower production of pods and seeds in these plants may be eliminated by selection in later generations of the autotetraploids.View full abstractDownload PDF (717K) -
T. Yabuya, H. Kikugawa, I. Aiko, T. Adachi1992 Volume 57 Issue 2 Pages 253-257
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSCytological studies of hybrids between the aneuploid variety “Ochibagoromo” (2n=25) and the eu-diploid variety “Shishinden” (2n=24) of Iris ensata were made. Among the hybrids (2n=24) examined, F1-1 and F1-2 exhibited normal associations (12 II), and the mean chromosome association per cell was 0.13 I+11.93 II for the former and 0.29 I+11.86 II for the latter, respectively. This indicates that one of three single chromosomes of “Ochibagoromo” has full homology for the second longest m chromosomes of “Shishinden”. On the other hand, F1-3 showed a fairly lower frequency for normal associations than the former two hybrids. The mean chromosome association per cell was 0.98 I+11.16 II+0.24 III. Consequently, this hybrid exhibited the lowest pollen fertility among F1 hybrids due to the irregularity in chromosome associations. Moreover, comparative karyotypic analysis between F1-1 and F1-3, and the meiotic data of F1-3 clarified that this irregularity was caused by structural changes of chromosomes such as translocation and deficiency. Finally, the origin and the development of the aneuploid varieties are discussed.View full abstractDownload PDF (704K) -
B. C. Patil, G. I. Bhat1992 Volume 57 Issue 2 Pages 259-264
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSRelative effects of MH (Growth retardant) and EMS, (Chemical multagen) with respect to mitotic behaviour has been assessed on lateral roots of the seedlings of C. tennatea Var. blue single. Roots have been treated with MH (10-4M, 10-3M and 10-2M), EMS (0.15%, 0.2%, 0.25%) for 2hr. After different recovery periods, (12 hr, 24 hr, 48 hr, 72 hr) mitotic analysis were carried out to estimate the cytological anomalies. In control 2.68% of chromosomal aberrations have been recorded. In both the treatments, common type of abnormalities observed were stickiness, bridges, laggards at anaphase and telophase. In case of EMS treatment study indicates chromosomal damage, however, it does not affect the mitotic inhibition, whereas, MH at higher concentration (10-2M) and all time factors of recovery period exhibits inhibition action on cell division leading to growth retardation, on the contrary, at lower concentration (10-4M) with various recovery period there is no mitotic inhibition but cells show good percentage of chromosomal aberrations conveying its mutagenic activity like EMS.View full abstractDownload PDF (1023K) -
P. T. Annie, P. G. Nair1992 Volume 57 Issue 2 Pages 265-266
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSCytological studies of very young endosperm of two species of Oryza were conducted. In the cultivated diploid Oryza sativa the endosperm tissue was triploid [3n=36 (3x)] and there was no endoplyploidy or other mitotic abnormalities. In the wild tetraploid O. malampuzhensis in addition to the normally hexaplid chromosome number [3n=72 (6x)], endopolyploidy [3n=144 (12x)] were also met with through C-mitosis type of division.View full abstractDownload PDF (700K) -
R. N. Singh1992 Volume 57 Issue 2 Pages 267-271
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSAutotetraploidy was induced in P. hybrida (white) and meiosis showed the presence of more multivalents and univalents in first generation. Meiosis of induced autotetraploid have more than sixty percent meiotic irregularities due to the presence of multivalents. At anaphase I, maximum chromosomes were lagged and oriented into three equatorial plates and lastly formed hexad. Pollen fertility is also lowered up to 79 percent in C1 generation and recovered in C2 generation due to decrease in the number of multivalents as well as univalents in pollen mother cells.View full abstractDownload PDF (920K) -
M. S. Lakshmi, C. Parker, G. V. Sherbet1992 Volume 57 Issue 2 Pages 273-276
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe MTS1 gene is a metastasis associated gene. In situ hybridization of human lymphocyte metaphase chromosomes with 18A2/MTS1 RNA probe has mapped the gene to chromosome 7q22.View full abstractDownload PDF (224K) -
R. N. Singh1992 Volume 57 Issue 2 Pages 277-281
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSAutotetraploidy was successfully induced in the genus Helianthus annuus L. and colchiploids were maintained for two generations. Meiotic chromosomal abnormalities were more than 50 percent in C1 generation and lowered in C2 generation due to decrease in the number of multivalents. Pollen as well as plant fertility (seed setting) was less in colchiploids but their size and weight were more in comparison to their diploid. The tendency for an increase in the number of bivalents during succeeding generations led to a gradual improvement in pollen and plant fertility.View full abstractDownload PDF (792K) -
T. V. V. Seetharami Reddi, J. Suneetha1992 Volume 57 Issue 2 Pages 283-288
Published: June 25, 1992
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe three cultivars of rice were treated with sodium azide and two alkylating agents EMS and MMS with a view to find out the frequency, spectrum, efficiency and effectiveness of chlorophyll mutations in relation to the genotype and the nature of the mutagen. Chlorophyll mutation frequency was enhanced with increasing dose but dropped at very high doses. Among the chlorophyll mutants induced viridis type formed the majority class. Effectiveness decreased with increase in dose with a few exceptions. Efficiency was more in the alkylating agents treated populations.View full abstractDownload PDF (332K)
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