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Volume 56, Issue 1
Displaying 1-22 of 22 articles from this issue
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Yoshikane Iwatsubo, Naohiro Naruhashi1991 Volume 56 Issue 1 Pages 1-10
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSInvestigation of the karyotypes and the first meiotic metaphase in pollen mother cells was carried out on 9 species of Japanese Potentilla; P. sprengeliana (2n=14), P. togasii (2=14), P. fragarioides (2n=14), P. toyamensis (2n=14), P. riparia (2n=14), P. yokusaiana (2n=14), P. freyniana (2n=14), P. sundaica var. robusta (2n=14), and P. chinensis (2n=14). The first seven species constitute the Potentilla fragarioides group, and had similar karyotypes. The last two species belong to distinct taxonomic groups and had different karyotype features. The first meiotic metaphase chromosomes of pollen mother cells showed regular bivalent formation in all nine species. It was clear from this investigation that the classification into three groups on the basis of chromosomal features agrees with the taxonomic treatment of the examined species.View full abstractDownload PDF (3843K) -
N. Subramonian1991 Volume 56 Issue 1 Pages 11-15
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSSugarcane c.v. CoC 671 (2n=108) was crossed with sweet sorghum (Sorghum bicolor L. 2n=20) and the hybrids obtained had the chromosome number varying from 2n=60 to 64. At meiosis, 6-11 univalents, 11-25 bivalents, 0-3 trivalents and 0-3 qadrivalents were observed. The chromosome associations, other than bivalents, indicate the influence of sorghum genome in chromosome pairing. Even though the hybrids were completely pollen sterile, few back-crossed progenies were obtained when pollinated with sugarcane pollen. In the BC1 plants, the chromosome number varied from 2n=48 to 118.View full abstractDownload PDF (750K) -
S. Muhanno, A. Souvré, L. Albertini1991 Volume 56 Issue 1 Pages 17-25
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSGamma irradiation of seeds (100 to 1000 Gy) or inflorescences (3000 Gy) of Nicotiana tabacum L. var. xanthi Dulieu mainly induced chromatoclastic effects affecting the microspore mother cells (MMCs) during meiosis: chromosome fragmentation, chromosome stickiness promoting the formation of chiasmas even between non-homologous chromosomes, single or multiple chromosomal bridges during anaphases and telophases I and II and irregular chromosomal disjunction.
In plants raised from irradiated seeds, the frequency of abnormal meiotic figures and the rate of pollen sterility were directly related to the gamma ray dose. Gamma irradiation also induced the early dysfunction of the tapetum (tapetal degeneration was already visible at pachytene) with nuclear pycnosis or an expanded and sticky chromatin network and this no doubt contributed to pollen sterility.View full abstractDownload PDF (2735K) -
A. B. Sapre, Anjali S. Naik1991 Volume 56 Issue 1 Pages 27-29
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSAmong aneuploid constitutions, higher polysomics occur only rarely, but constitutions above tetrasomics hardly survive in Nature. However, Coix gigantea (2n=20, Tribe-Maydea, Family-Poaceae) is chromosomally highly plastic. While a series of aneuploids from nullisomy (2n-2, 2n=18) to hexasomy (2n+4, 2n=24) has been isolated and studied cytologically earlier, a higher polysomic of the order of octosomic (2n+6, 2n=26) has been isolated from among the selfed progeny of a tetrasomic plant (2n+2, 2n=22). Important cytological configurations are reported.View full abstractDownload PDF (408K) -
Tasneem F. Khaleel, Susan Haven, Tim Gilg1991 Volume 56 Issue 1 Pages 31-41
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSKaryotype analysis, genome analysis and development of gametophytes is described for nine hybrids of garden Amaryllis. The basic chromosome number is x=11 and all nine hybrids are tetraploid with a bimodal distribution favoring long and short lengths. The basikaryotype proposed by Narain and Khoshoo (1968) which consists of two median, five submedian and four subterminal chromosomes, is not traceable in any of the nine hybrids. 2A5SM4M and 4A4SM3M are the most common basikaryotypes in six out of nine hybrids. All hybrids show altered karyotypes. Chromosomes range from 4.3-17.7μm in length. The total chromatin ranges from 307.6μm-502.5μm. Bivalents, trivalents and quadrvalents are formed during meiosis. About 20-40% of the pollen grains are sterile. Development of the megagametophyte is monosporic in 90% of the ovules and bisporic in the remaining 10%. All nine hybrids show 80-90% degeneration of embryo sac at various stages of development. The fruiting behaviour and low percentage of seed set are associated with pollen sterility, and degeneration of embryo sacs.View full abstractDownload PDF (2408K) -
Annie T. John, Susan Abraham1991 Volume 56 Issue 1 Pages 43-46
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSIncorporation of black pepper (50 to 200mg/kg body weight) into diet of mice showed significant effect on the incidence of structural and numerical abnormalities in the bone marrow cells. The frequency of total aberrations showed a linear relationship with dose. The data were statistically analysed.View full abstractDownload PDF (742K) -
S. Rama Rao, K. P. S. Chandel1991 Volume 56 Issue 1 Pages 47-57
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSKaryological details have been investigated in 12 morphologically distinct species/forms including both cultivated and wild occurring putative progenitors of domestivated Vigna species. Data on chromosome number, morphology, nucleolar organizers, symmetry/asymmetry of the karyotypes has been recorded. The pattern of karyological differentiation and karyotypic evolution in the asiatic wild taxa vis-a-vis cultivated forms has been discussed. Difference in the pattern of karyotype evolution in asiatic and african wild taxa was also assessed.View full abstractDownload PDF (1240K) -
F. S. Kubrusly, M. L. S. Mello1991 Volume 56 Issue 1 Pages 59-62
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSA variable effect of Cu2+ and Hg2+ ions on the intensity and localization of the SDH activity was cytochemically detected in the Malpighian tubule cells of the blood-sucking insect, Triatoma infestans. Unaffected and decreased enzyme activities as well as a change in the spatial distribution of mitochondria were detected on the basis of the cytochemical localization of the enzyme. It is assumed that these metal ions could affect not only the mitochondrial performance but also other cell functions which require a specific mitochondrial distribution.View full abstractDownload PDF (705K) -
Promila Runthala, Sima Bhattacharya1991 Volume 56 Issue 1 Pages 63-72
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe present investigation deals with the effect of static magnetic field of 2.25×103 Gauss on the mitotic and meiotic divisions and nucleoli of root meristematic cells of Alllum cepa L. In the present effort the effect of static magnetic field was compared with that of electro-magnetic field (He-Ne Laser beam of 2 mW) also.
A significant fall in mitotic indices was noticed on static magnetic field whereas such fall was found much sharply in case of electrimagnetic field. Such treatment was also associated with various anomalies e. g. stickiness, clumping of chromosomes, anaphase chromosome bridge and disturbed spindles.
Although a significant increase in meiotic indices was noticed due to static magnetic field after 30 minutes compared to the control, a considerable decrease in the frequency of cells at metaphase stage was recorded indicating the role of spindle abnormality due to magnetic field. Various meiotic abnormalities were also recorded.
Average nuclear and nucleoar size was found decreased significantly due to magnetic field treatment with the increase in time of treatment. Since the nucleolar size is a reliable reflector of nucleolar activity, such decrease may be correlated to the mitostatic activity of the cells.View full abstractDownload PDF (2585K) -
A. K. Sharma, D. C. Gautam1991 Volume 56 Issue 1 Pages 73-78
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSChromosomal damage induced by two pesticides viz. phosphamidon and endosulfan employing in vivo chromosomal aberration bioassay in bone marrow cells of male albino mice of Lacca strain (Mus musculus) have been investigated. Different doses tested for phosphamidon (2.55, 2.98 and 3.40μg/g, b. wt.) and for endosulfan (1.75, 3.50 and 5.25μg/g, b. wt.) were injected intraperitoneally. The observations were recorded at time intervals of 1, 2, 5 and 10 days. Both clastogenic as well as physiological types of aberrations were induced by these pesticides. The clastogenic type aberrations induced by phosphamidon and endosulfan in the bone marrow cells of mice include chromosomal fragmentation, chromatid breaks, chromosomal and chromatid gaps, ring chromosomes, interchromatid exchanges, minutes and dicentric chromosomes. Physiological type of aberrations caused by both of these pesticides include centromeric associations, exchange configurations, bizarre configurations, shrinkage of chromosomes, stickiness and end to end associations. Generally, it was observed that the chromosomal aberrations are more at higher doses as compared to lower doses tested in the present investigations.View full abstractDownload PDF (811K) -
Georgiana M. Jagiello, Jye-Siung Fang, Mercedes B. Ducayen1991 Volume 56 Issue 1 Pages 79-82
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSA study of total chiasma frequencies in the diplotene oocytes of mice heterozygous for Robertsonian translocations, X-autosomal translocations, paracentric inversions as well as the XX progeny of XO mothers revealed a decrease in all but one genotype. These data present the first analysis of potential interchromosomal effects on crossing over in mouse oogenesis.View full abstractDownload PDF (756K) -
I. Kar, A. R. Khuda-Bukhsh1991 Volume 56 Issue 1 Pages 83-86
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe diploid number of 10 chromosomes has been claimed by some workers in Lipaphis erysimi, a polyphagous species of aphid while the diploid number of 8 was suggested by others. In the present study, both Giemsa-stained and Silver-nitrate stained preparations confirmed 2n=8 chromosomes in L. erysimi, and the NORs were revealed as a discrete silver-positive dot at one end of two large-sized chromosomes. It has been hypothesized that the dissociation of one or two fragments at SC sites might have led to the origin of 2n=9 or 10 chromosomes which have occasionally been observed by various workers.View full abstractDownload PDF (659K) -
R. N. Singh1991 Volume 56 Issue 1 Pages 87-93
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSAutotetraploidy was induced in Phlox drummondii Hook. with aim to enhance the ornamental value as well as seed out put. Meiotic studies revealed highly irregular meiosis in C1 lesson in C2 generation. Meiotic abnormalities in the C2 generation increased pollen sterility which lowered seed setting. High bivalent and low multivalent frequencies in the PMCs in C2 generation led to a improvement on pollen and plant fertility.View full abstractDownload PDF (764K) -
L. S. Mini, J. Christopher, Benny Jacob1991 Volume 56 Issue 1 Pages 95-102
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSDetailed cytological analysis including karyomorphology, meiosis and pachytene studies have been carried out for the first time in Hygroryza aristata, a monotypic genus belonging to the tribe Oryzeae. Incidentally this is also the first report on pachytene studies of another genus of this tribe, as all previous pachytene studies have been confined to a few species of Oryza only. Meiosis showed secondary association of bivalents, association in a 3-5 groups of two bivalents each were commonly observed. Pachytene chromosomes were of the differentiated type, the unstained centromeres were flanked by proximal dark-staining heterochromatic regions and distal light staining euchromatic regions. There is complete pairing between all homologous chromosomes. Two bivalents were found constantly associated with the nucleolus at pachytene and diakinesis and four chromosomes with secondary constrictions were observed at somatic metaphase. The pachytene analysis clearly demonstrates that chromosomes VI and VIII and also XI and XII are morphologically similar and appear as duplicated types. The body of evidence clearly indicates that the monotypic Hygroryza and Oryza, which are grouped togehter on the basis of morphological characters show close resemblance in their cytological behaviour also.View full abstractDownload PDF (934K) -
Hongchang Ma, C. E. Wassom, G. H. Liang1991 Volume 56 Issue 1 Pages 103-106
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSAnther culture of maize (Zea mays L.) usually follows an indirect procedure involving callus induction and differentiation on at least two different media. Alternately, development of a direct procedure by which plantlets can be regenerated directly on one medium seems desirable, if acceptable frequency of plant regeneration can be obtained and an effective procedure of chromosome doubling of regenerates is available. We used Yupei (YP) and N6 basal media and 10 growth regulators (2, 4-D, kinetin, NAA, IAA, IBA, dicamba, pCPA, 6-BA, 2ip, and hypoxanthine) to test the feasibility of direct generation of haploid plantlets on six single-cross hybrids, 12 inbred lines, one teosinte (Zea mays ssp. Mexicana), and a hybrid between teosinte and maize. The results indicated that the direct generation of plantlets is feasible through anther culture, though it is genotype- and medium-dependent. Ten plantlets were generated directly from single cross hybrid K809 × A 619W and A2-1. The most effective medium was N6 basal medium plus 2, 4-D (2.0mgl-1) and kinetin (1.5mgl-1). Regeneration frequency (percent of anthers producing plantlets) ranged from 1 to 4%.View full abstractDownload PDF (1641K) -
S. Muhanna, A. Souvré, L. Albertini1991 Volume 56 Issue 1 Pages 107-115
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSWhen a high dose of gamma irradiation was applied to the seeds (500-1000 Gy) or directly to the inflorescences (3000 Gy) of Nicotiana tabacum L. var. xanthi Dulieu, there was a marked decrease in the DNA content (20 to 40%) both of the nucleus of the pollen mother cells (PMCs) at pachytene and the two endomitotic nuclei of the corresponding tapetum cells. When inflorescences were directly irradiated (3000 Gy) before 3H-thymidine application, there was a reduction in the labelling of the PMCs and tapetum (75 to 94%) due both to an inhibition of DNA synthesis by the chromatin remaining in situ and a loss of chromatin by elimination of chromosomal fragments. Under these last conditions, the incorporation of 3H-uridine in the chromatin, nucleolar and cytoplasmic RNA was also strongly inhibited (70 to 90%) in PMC and tapetum cells.View full abstractDownload PDF (1433K) -
Girish Kumar1991 Volume 56 Issue 1 Pages 117-123
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSModification of induced genetic damage after exposure to LD50 and LD90 doses of 60Co gamma-irradiation on dormant seeds of Solanum incanum L. by pre- and post-treatments of thiourea was investigated. Thiourea pre-treatment reduced cellular lesions, growth injury and the death of seedlings, while post-treatment increased lethality. Incorporation of 3H-tymidine into DNA fraction gradually increased with 10-4 to 10-2 M thiourea treatment when applied before irradiation. Post-treatment of the thiourea, on the other hand, not only showed poor labelling of DNA but also delayed its synthesis.View full abstractDownload PDF (488K) -
C. A. Fatokun1991 Volume 56 Issue 1 Pages 125-129
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSA pepper plant showing malformed leaves and flat stem was dicovered in a line being assessed for agronomic performance. This plant was also found to be partially male sterile. Pollen grains were variable in size and about 40.2 percent of these did not stain at all with acetocarmine. Cytological investigations showed that the high frequency of non-viable pollen was due mostly to asynapsis. Chromosomes were precociously separated and some were lagging even at telophase II. Micro-nuclei were formed in some pollen mother cells and these gave rise to the small, non-viable pollen grains. The possibility of exploiting this partial male sterility for pepper improvement purpose was highlighted.View full abstractDownload PDF (1820K) -
Kuldeep Kumar Koul, R. N. Gohil1991 Volume 56 Issue 1 Pages 131-133
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSMeiosis of Poa trivialis L. has been studied in detail for the first time. The meiotic studies revealed the presence of a new chromosome count i. e. n=36+1 ec which is also the highest chromosome number reported for this taxon. Meiosis is highly irregular characterized by the presence of varying number of quadrivalents and trivalents besides bivalents and univalents both at diplotene and metaphase-I stages resulting in highly erratic anaphase segregation. The presence of multivalents indicate towards its segmental allopolyploid nature with little homology between constituent genomes.View full abstractDownload PDF (578K) -
Hiroshi Okada1991 Volume 56 Issue 1 Pages 135-141
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSCorrespondence of banding patterns of Giemsa C-band and DAPI/CMA fluorochromes of the same specimen of Aconitum sanyoense was examined. It appeared that there were various C-bands, that is, AT-rich (C+/DAPI+/CMA-), GC-rich (C+/DAPI-/CMA+), and intermediate (C+/DAPI-/CMA-) C-bands. Furthermore, some so-called euchromatic segments showed AT-rich DNA sequences (C-/DAPI+/CMA-). Determination of the combination of these banding patterns may advance detailed detection of cytogenetical variation among individuals of this species.View full abstractDownload PDF (1868K) -
Naohiro Naruhashi, Yoshikane Iwatsubo1991 Volume 56 Issue 1 Pages 143-149
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe present investigation on the chromosomes of Duchesnea confirmed previous reports indicating that D. chrysantha f. chrysantha has 2n=14 chromosomes and D. indica has 2n=84 chromosomes. The chromosome number of D. chrysantha f. leucocephala, 2n=14, was also ascertained, together with the meiotic chromosome numbers. The two taxa of D. chrysantha had very similar complements consisting of 5 pairs of metacentrics, one pair of metacentric SAT-chromosomes and one pair of submetacentrics. Duchesnea indica had subtelocentric SAT-chromosomes and many subtelocentric chromosomes in addition to metacentric and submetacentric chromosomes. The genome of D. indica contains a genome set involving subtelocentric chromosomes, which were not detected in D. chrysantha. This finding seems to be of importance in considering the course of evolution in D. indica.View full abstractDownload PDF (1133K) -
Yoshikane Iwatsubo, Naohiro Naruhashi1991 Volume 56 Issue 1 Pages 151-156
Published: March 25, 1991
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThree taxa in Rubus (Rosaceae): R. parvifolius, R. coreanus, and R. × hiraseanus, a presumed spontaneous hybrid between the former two described by Makino in 1902, were investigated cytologically. The somatic chromosome numbers were found to be: 2n=14 for R. parvifolius and R. coreanus and 2n=21 for R. × hiraseanus. The chromosome number of the latter was determined for the first time. The karyological features of R. parvifolius and R. coreanus were similar, and further gross similarity was also observed in the chromosomes of R. × hiraseanus, although the size of the satellites and ploidy level differed. The chromosome configurations found in the PMCs of R. × hiraseanus displayed frequent trivalent formation, indicating that R. × hiraseanus may comprise three homologous sets of chromosomes. This study indicated the possibility of a close relationships, but failed in elucidating an origin for R. × hiraseanus.View full abstractDownload PDF (2172K)
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