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Zacharias G. Scouras, Costas D. Kastritsis
1988 Volume 53 Issue 2 Pages
213-218
Published: June 25, 1988
Released on J-STAGE: March 19, 2009
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The distribution of intercalary heterochromatin in the salivary gland polytene chromosomes of
Drosophila auraria is presented in this report, as revealed by the tendency of certain regions to pair ectopically, and by the existence of weak points. The two well-formed Balbiani rings, which are known to exist in this species, and the largest early ecdysone puff 73B, which corresponds to the puff 75B of
D. melanogaster, seem to involve intercalary heterochromatin. Several pairings of nucleolar chromatin with certain chromosomal bands, as well as similarities in the intercalary heterochromatin distribution between
D. auraria and
D. melanogaster, are also presented.
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Jordanka Georgieva-Todorova
1988 Volume 53 Issue 2 Pages
219-225
Published: June 25, 1988
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Results presented in this paper are concerning the hybridization between the cultivated sunflower (
Helianthus annuus, 2n=34) and the tetraploid species
H. decapetalus (2n=68).
The analysis of F
1 hybrids between
H. annuus and
H. decapetalus and the study on the effect of backcrossing on cytological and phenotypical stabilization substantiate the conclusion that
H. decapetalus, although not very closely relating to
H. annuus, could be used in sunflowers hybridization programmes.
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S. E. A. Younis, R. F. Abdou, T. H. I. Sherif
1988 Volume 53 Issue 2 Pages
227-231
Published: June 25, 1988
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Due to the mutagenic effects of several pesticides, drugs, and chemicals used daily by man, several studies started to investigate the mustagenic effects of the new released ones. Nuvacron, the Ciba product is a systemic insecticide used against cotton leafworm, potato tuber moth and other insects. It is an organo-phosphorus compound having 4 methyl groups and highly toxic.
Vicia faba dry seeds were treated with 6 fresh diluted solutions while growing seedlings were treated with only 2 concentrations of Nuvacron in addition to the control one. The roottips were fixed and cytological studies were carried out. The results showed gradual reduction in the mitotic index by increasing the concentration and significant gradual increase in the inhibition and the induced aberration percentages by the increase in the concentration. The treated seedling root-tips were less affected due to the repair mechanism. The Nuvacron induced about 63% chromosome bridges, 13% fragments, 9% lagging chromosomes and 1% rings of the total induced aberrations. The presence of induced tetraploids and disturbed chromosomes may be due to the effect on the spindle fibers in addition to the effect on DNA.
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J. A. Adegoke
1988 Volume 53 Issue 2 Pages
233-239
Published: June 25, 1988
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The chromosomes of the Rainbow lizard,
A. agama agama have been studied from bone marrow and testis preparations. The animal has a diploid chromosome complement of 44 with a fundamental number of 46. The karyotype bears very close relationship to that of
A. atra from South Aftrica. Several spermatocytes in diakinesis and metaphase I show polyploidy which may be regular or apparent. The incidence of the regular polyploids varies from one animal to the other, although averagely about 4.8% of all cells in diakinesis are of the tetraploid origin while other ploidy levels account for 0.4%. Quadrivalents were not found in these polyploid cells and a process of endoreduplication of chromosomes without separation of sister chromatids is suggested for their origin.
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B. G. Sangowawa
1988 Volume 53 Issue 2 Pages
241-243
Published: June 25, 1988
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The chromosomes of West African
S. melongena L. var.
Gawagwda were studied from the roottips and the tapetum. The diploid chromosome number is 24, consisting of 8 fairly large-, 8 medium- and 8 small-sized chromosomes. According to the system of classification used, the chromosomes are grouped into three, one sub-median, nine with nearly submedian and two with nearly median chromosomes.
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Jean Dexheimer, Joëlle Serrigny, Joëlle Gerard
1988 Volume 53 Issue 2 Pages
245-253
Published: June 25, 1988
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Les auters étudient l'organisation ultrastructurale et la localisation de diverses activités enzymatiques (ATPases, phosphatases neutres, phosphatases acides) dans le champignon symbiote isolé et associé.
Les structures pariétales présentent des modifications remarquables et sont caractérisées par une simplification de la structure et un amincissement important dans le champignon associé.
De même, les activités ATPasiques et phosphatasiques neutres présentent une localisation différente dans le champignon isolé ou associé. Dans ce dernier, leur localisation sur le plasmalemme est interprété comme étant l'indication de l'existence d'échanges actifs entre les deux partenaires de la symbiose.
Les activités phosphatasiques acides montrent une localisation diffuse dans le cytoplasme dégénérescent du champignon isolé ou associé. Elles corespondent à l'autolyse du cytoplasme fongique. Dans les hyphes juvéniles du champignon associé les activités phosphatasiques acides du plasmalemme sont absentes (inhibition par la cellule-hôte ?).
Cette étude met en évidence les changements structuraux et métaboliques qui affectent le champignon lorsqu'il entre en symbiose.
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B. V. Rao, B. G. S. Rao, C. B. S. R. Sharma
1988 Volume 53 Issue 2 Pages
255-261
Published: June 25, 1988
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Cytological effects of two herbicides viz., asulum and MSMA and two insecticides viz., chlorpyriphos and endosulfan were tested on
Allium cepa root meristems. One hour pulse treatments were given with test solutions at different concentrations and allowed to different recovery periods in Hoagland's nutrient solution.
Among the test pesticides MSMA was observed to be the most effective clastogenic as well as turbagenic agent followed by endosulfan, chlorpyriphos and asulum respectively in that order.
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G. P. Sharma, R. C. Sobti, A. Chaudhry, K. K. Ahluwalia
1988 Volume 53 Issue 2 Pages
263-267
Published: June 25, 1988
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The effects of two heavy metal compounds viz., lead acetate and mercuric chloride were studied on the polytene chromosomes in
Anopheles stephensi. Various chromotoxic effects such as inversions, translocations, and breaks were observed. In the larvae treated with lead acetate, an increased incidence (as compared to controls) of asynapsis in the X-chromosome was also observed. From the present studies, it is evident that lead acetate is a weak mutagen, whereas the use of mercury needs more cautions.
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C. Singh, A. P. Shamsherry
1988 Volume 53 Issue 2 Pages
269-273
Published: June 25, 1988
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Biological effects of Propane sultone under varied conditions of treatment such as presoaking, post washing, redrying and storage were studied in barley. A higher mutation frequency of mutagenic effectiveness and mutagenic efficency was observed in treatments involving presoaking and post washing for 8-16 hrs. Redrying of mutagen treated seeds to 10 and 20% moisture content enhanced mutation frequency but not efficiency, while storage for 4 weeks potentiated both the mutation frequency and efficiency of PS mutagenesis.
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Shubhada Patankar, P. K. Ranjekar
1988 Volume 53 Issue 2 Pages
275-281
Published: June 25, 1988
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The staining and structural hehaviour of heterochromatin during meiotic division was compared with that in mitosis in
Allium cepa and
Rhoeo discolor. The constitutive heterochromatin is telomeric in
A. cepa and centromeric in
R. discolor. The behaviour and position of heterochromatin during meiotic division is essentially similar to that in mitosis. In
A. cepa, in addition to telomeric bands, granule like structures (probably kinetochores) are also occasionally stained during diplotene and metaphase I. The heterochromatin appears to be taking an active part in meiotic pairing in both the species. However, the direct causal relationship between the two cannot be inferred. Although the role of heterochromatin is same, our data indicate the difference in its behaviour during pairing.
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B. N. Verma, C. N. Jha
1988 Volume 53 Issue 2 Pages
283-286
Published: June 25, 1988
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The filaments of
Rhizoclonium kuetz were treated with 0.05%, 0.1% and 0.15% of dES for 9 hrs at pH 7 and temp. 20°C in dark. 0.05% was found ineffective while 0.1% and 0.15% induced mitotic disorders like laggings, bridges, micronuclei and changes in the orientation of anaphasic axis. Normal nuclear division was restored between 72 hrs and 168 hrs after treatment, except indication of lethality of 0.15% by the presence of micronuclei even after a month. Deformation of cells, change in the number of nuclei per cell and increase in the diameter of nuclei were seen in 0.1% and 0.15% treated filaments after 168 hrs.
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R. N. Gohil, Kuldeep Kumar Koul
1988 Volume 53 Issue 2 Pages
287-290
Published: June 25, 1988
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Meiosis of
A. filipes Hook. f. has been studied for the first time. The meiotic studies revealed it to be a hexaploid, with n=21. Meiosis in this species is highly irregular characterized by the presence of multivalents, bivalents and univalents at diplotene and metaphase I, resulting in irregular anaphase I segregation. Meiotic behaviour of this species points towards its segmental allohexaploid nature, with little similarity between consitituent genomes.
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S. S. Bir, G. S. Chatha
1988 Volume 53 Issue 2 Pages
291-296
Published: June 25, 1988
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From amongst four species of
Pavetta cytologically analysed from Palni hills, south India, secondary associations of chromosomes are reported for
P. breviflora var.
subcoriaceae. Commonly observed groupings of chromosomes are 2(3)+2(2)+1(1) both at MI and AI. This suggests that the basic number 11 of
Pavetta could have evolved from 5 and 6 through amphidiploidy. Species status is proposed for the taxon in view of chromosomal pecularities coupled with morphological and habit differences so evident from
Pavetta breviflora
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M. Z. Beg, A. H. Khan
1988 Volume 53 Issue 2 Pages
297-306
Published: June 25, 1988
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Solanum villosum ssp.
puniceum (2n=48) and diploid
S. nigrum (2n=24) were crossed among themselves and the resulting triploid hybrids (2n=36) were completely pollen sterile (1.07 per cent pollen fertility). The triploid hybrids were raised to hexaploid level by giving the colchicine treatment. These synthesized hexaploids (2n=72) were compared statistically with natural Indian hexaploid
S. nigrum and it was found that they were morphologically very much similar to each other. The cytological studies of colchiploids also revealed the formation of normally 36 bivalents like natural Indian hexaploid
S. nigrum. Successful reciprocal cross was made between synthesized and natural Indian hexaploids
S. nigrum and the resulting hybrids were fully fertile with normal meiosis. The hybrid set normal fruits with viable seeds. This supports the genomic closeness of colchicine induced hexaploids and natural Indian hexaploid
S. nigrum L. On the basis of our findings it can be concluded that diploid
S. nigrum and
S. villosum ssp.
puniceum may be the putative parents which have played an important role in the orgin of natural Indian hexaploid
S. nigrum.
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VI. Intrapopulational and/or intraspecific variation in the karyotype of L. sanguinea Max. var. kiushiana and L. sanguinea Max. var. koreana (Nakai) Koyama
Siro Kurita
1988 Volume 53 Issue 2 Pages
307-321
Published: June 25, 1988
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Intraspecific variation of the karyotype of
L. sanguinea var.
kiushiana and
L. sanguinea var.
koreana was studied. Almost all plants of both taxa examined were diploid having 2n=22, but three triploid bulbs (2n=33) and one tetraploid bulb (2n=44) were found in
L. s. var.
kiushiana from the Taradake population. The absolute arm length, relative length, and
r value of each chromosome of the representative karyotype of these taxa have been summarized in Tables. The standard karyotype of diploid plants consists of twenty-two
A type chromosomes of which two are satellite chromosomes.
Though the frequency is low, various intraspecific and intercellular chromosome rearrangements were observed in the diploid. They are as follows: 1. Some subtelocentric chromosomes and
T' type chromosomes were observed. They must have originated from the standard
A type chromsomes by means of deficiency or pericentric inversion. 2. The
m type chromosome was found in some cells of
L. s. var.
koreana. It must have originated from the
A by means of a break at the proximal region of the long arm. 3. A few instances of heterozygous combination of satellite chromosomes were observed.
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VII. Modes of karyotype alteration within species and probable trend of karyotype evolution in the genus
Siro Kurita
1988 Volume 53 Issue 2 Pages
323-335
Published: June 25, 1988
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Yohichi Hashimoto, Reiko Nakamura, Takeo Muroyama, Takuzo Yamada
1988 Volume 53 Issue 2 Pages
337-340
Published: June 25, 1988
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Specific characters of small fruiting bodies of the cellular slime mold have been investigated. Cell number increase was most frequently observed during morphogenesis, when number of initial cells exceeds 300. Cell division during morphogenesis was not necessarily requisite for cell differentiation, since cells formed fruiting bodies, even if there was no increase in cell numbers.
Ratio of stalk cells to total cells was 14-23% when the total cell number was around 100. The ratio decreased down to 3-7% with cell number increase of a fruiting body.
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U. P. Singh, R. Saikumar, R. M. Singh, R. K. Singh
1988 Volume 53 Issue 2 Pages
341-346
Published: June 25, 1988
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Twenty five interchange trisomics were isolated from an interchange trisomic and six translocation heterozygotes of pearl millet (2n=14). Morphology and fertility of these trisomics varied from plant to plant and season to season. Cytological analysis of these trisomics indicates that chromosome associations of trivalents and univalents were frequent with comparatively less frequency of _??_
4 and pentavalents in all the trisomics studied. Other associations were relatively infrequent. Transmission rate and breeding behaviour of 18 interchange trisomics were studied for three seasons of the crop and it was found that average frequency of primary trisomics was more than that of other trisomics (tertiary and interchange). The possible causes of differential transmission rates of different trisomics have been discussed.
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Anuradha A. Sathe, P. V. Joshi
1988 Volume 53 Issue 2 Pages
347-352
Published: June 25, 1988
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Morphology and histology of spermatheca of seven orthopteran insects is compared. None of the spermathecae are associated with spermathecal accessory gland. Observations reveal that the spermatheca, which is in the form of a sac, has single layered epithelium while spermatheca with apical appendage, or in the form of sperm storing tubules, has double-layered epithelium. The double-layered epithelium is probably more evolved where the outer layer is secretory and the inner is chitogenous in nature.
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Maria Joseph, D. G. Krishnappa
1988 Volume 53 Issue 2 Pages
353-358
Published: June 25, 1988
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Three diploid interspecific hybrids and two reciprocal hybrids were produced between the species of section Erectoides. The cytological analysis in two hybrids and their reciprocal crosses shows 10 bivalents at diakinesis and metaphase-I in most of the PMCs and 2-4 univalents are seen in about 10 to 15 percent of cells. Further the hybrid between
A. sp. 9990×
A. sp. 10002 reveals a ring of four chromosomes in approximately 18 percent of the PMCs. In the hybrid
A. regonii×
A. sp 9990 and its reciprocal, chromatin bridge is seen in 8.4 percent of the cells at anaphase-II, thus providing cytological evidences for the possible role of structural changes in speciation of the section Erectoides.
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Meiotic studies in diploid Musa species and banana varieties of India
P. K. Agarwal
1988 Volume 53 Issue 2 Pages
359-363
Published: June 25, 1988
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Meiosis in two
Musa species and eleven banana varieties showed high degree of bivalent formation at MI and regular distribution of chromosomes at A I and A II. In var. Chingan meiosis does not take place and pollen do not form. In other varieties (excepting
M. balbisiana, Kadali, Ambalakadali and Erachi vazhai) either pollen are completely absent or present in very little quantities. The sterility observed in these species/varieties is genic and not chromosomal. Based on present investigations and hybridization studies, it has been inferred that meiotic events leading to the formation of male gametes do not necessarily reflect the events taking place in formation of female gametes.
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D. Ohri, A. Kumar, M. Pal
1988 Volume 53 Issue 2 Pages
365-367
Published: June 25, 1988
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Two species of
Cosmos,
C. bipinnatus and
C. sulphureus show 2C nuclear DNA amounts of 3.08 pg and 5.98 pg respectively. This two-fold difference corresponds with their natural grouping taxonomically. A measurement of DNA amount of each chromosome within the complements of the two species shows that every chromosome of
C. sulphureus acquires an equal amount of ‘extra DNA’. Consequently, the size difference among the largest and the smallest chromosomes of the complements has become less in
C. sulphureus vis-à-vis
C. bipinnatus.
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Shyamal K. Roy, P. C. Datta
1988 Volume 53 Issue 2 Pages
369-378
Published: June 25, 1988
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Andrographis paniculata an well known indigenous drug plant of the whole Indian subcontinent, attracted attention for the diversity of ecological conditions of its abodes. Discovery of genetically distinct types, if chemically distinct, would certainly help in the selection of best strains. The simplest and quickest way of detecting genetical difference is the cytological techniques and study of chromosome morphology. Of course these cytological methods could detect only such genotypes which had structural alterations of chromosomes, but not pure genic changes or point mutations.
The chromosomal biotypes differed only in structure suggesting the occurrence of cytotypes within this species, brought about by translocation, deletion etc. These chromosomal changes probably made the cytotypes best suited to their environments, where they normally grew.
As in reports, many such cytotyes of other taxa, differ in micro- and macromorphological characters and chemical contents, these cytotypes were also suitable for analyticl study of quantitative anatomy, morphology and of the active principle available in this species.
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N. P. Singh, B. M. B. Sinha
1988 Volume 53 Issue 2 Pages
379-383
Published: June 25, 1988
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Cytological studies in
Cnidium monnieri of the family Umbelliferae have shown variability in chromosome number in the somatic cells from the same root tip, and the PMCs also exhibited variability in chromosome number and pairing behaviour. The taxon has shown stabilization at chromosome number 36 although a lower number 18 or higher number 72 has also been observed. It is considered to be a hybrid involving closely related taxa. The genetic control for regulation of pairing of chromosomes is either yet to be evolved or it has undergone a mutation which is reflected in multivalent formation in a few PMCs.
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Bhaskar P. Saxena, P. R. Sharma, K. Tikku
1988 Volume 53 Issue 2 Pages
385-391
Published: June 25, 1988
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Spodoptera litura was analyzed for its haemocyte types both light and scanning electron microscopically. A total of nine categories of cells were found on the basis of their surface morphologies. The identified cells are the prohaemocyte, plasmatocyte, vermicyte, podocyte, granular haemocyte, oenocytoid, spherulocyte, adipohaemocyte and coagulocyte. The plasmatocyte was seen to assume three shapes-the typical spindle, bean and barrel shape and only the bean-shaped cell has 1-2 pores on its surface. The vermicytes and podocytes differ considerably from plasmatocytes with regard to their surface specializations. The vermicyte exhibits many pores while podocyte, in addition, has a large number of lamellipods and filopods. Among the other cells, the prohaemocytes are very smooth and small, the granular haemocytes are covered with cytoplasmic projections and carry a shallow pit at one of their poles, the oenocytoids have almost negligible processes, the spherulocytes are characterized by a sculptured surface pattern, and the adiopohaemocytes are devoid of any specialization. The outer membrane of coagulocytes has a tendency to undergo disruption. Differential counts of these cells were also conducted from 3rd instar larva to the old pupa and all the types were seen to exist in these studies.
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Fuh Jiunn Pan, James L. Brewbaker
1988 Volume 53 Issue 2 Pages
393-399
Published: June 25, 1988
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In twelve
Leucaena taxa examined, the chromosome numbers were found to be n=26, 28 and 52. Six species and one subspecies have n=26, two species n=28 and three species n=52. Chromosome numbers in
L. collinsii Britton and Rose (n=26),
L. diversifolia (Schlecht.) Benth. ssp.
diversifolia Pan et Brewbaker (n=52),
L. pallida Britton and Rose (n=52) and
L. retusa Benth. (n=28) were reported for the first time. The meiosis was regular in all the diploids and in most tetraploids. Multivalents were found in some tetraploids. The chromosome pairing in some species hybrids showed that species genomes in the genus
Leucaena were very similar cytologically. Besides geographical and ecological isolation, polyploidy has played a very important role in the evolution of the genus.
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Steven J. Stegink, Kevin C. Vaughn
1988 Volume 53 Issue 2 Pages
401-406
Published: June 25, 1988
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Certain features of bacteroid ultrastructure in root nodules of
Aeschynomene spp. cor-relate with the ability of the plant to produce stem nodules. Bacteroids of root nodules of stem-nodulationg species are relatively complex structurally and contain extensive invaginations of the membranes, clusters of DNA organized into nucleoids, and several electron opaque inclusions. The bacteroids in all of the stem-nodulating
Aeschynomene species examined are generally enclosed singly in peribacteroid membranes and are oval-shaped. The bacteroids of non-stem nodulating species are varied in morphology (pleomorphic, rods and near ovals) and contain much less extensive invaginations of the membranes than the stem nodulating species. Some characteristics, such as the absence of interstitial cells and lack of infection threads, are found throughout the
Aeschynomene root nodules examined. These data indicate that bacteroid ultrastructure might seve as structural clue as to potential stem-nodulating species and may relate to an underlying metabolic difference between stem-nodulating and non-stemnodulating spp.
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G. Salesses, A. Bonnet
1988 Volume 53 Issue 2 Pages
407-413
Published: June 25, 1988
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Certaines variétés cultivées de noisetier sont caractérisées par une stérilité mâle partielle liée à la présence d'une translocation à l'état hétérozygote (F. de Coutard, Segorbe, Négret, Ronde du Piémont et Tonda di Giffoni).
Une étude cytologique d'hybrides issus du croisement de ces cinq variétés, deux à deux, permet de montrer que les paires chromosomiques impliquées dans ces remaniements sont les mêmes pour l'ensemble des variétés à l'exception de Tonda di Giffoni.
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Suchitra Banerjee (nee Chattopadhyay), A. K. Sharma
1988 Volume 53 Issue 2 Pages
415-420
Published: June 25, 1988
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Cytological studies have been carried out on five different species of
Agave, collected from different parts of India. All of them revealed diploidy having 2n=60 chromosomes. A distinct bimodal karyotype with very long and very short chromosomes in a definite proportion of 5:25 ratio is the most significant characteristic of this genus. However, the karyotype formulae, as brought out in the present study differ quite distinctly amongst the species in-vestigated. Such variations principally involve the nucleolar chromosomes of both long and short types. The total chromosome lengths and volumes also differ at the interspecific level. Structural alterations along with differential degrees of coiling of chromosomes are the suggested factors principally responsible for such variations.
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Panuganti N. Rao, A. Nirmala, P. Ranganadham
1988 Volume 53 Issue 2 Pages
421-425
Published: June 25, 1988
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In two wholly unrelated populations of pearl millet (
Pennisetum americanum (L.) Leeke), four spontaneous triploids (3n=21) and in the progenies of triploids, one hypertriploid (3n=22) and two hypotriploids (3n=20) were found. Cytological studies were made at meiosis on PMCs. In all these, trivalents, bivalents and univalents were found in varying frequencies. In the hypertriploid, however, besides a quadrivalent expected, associations of 6 and 5 chromosomes were also found indicating the presence of a reciprocal transolcation between non-homologous chromosomes. In one hypotriploid, a chromosome of the nucleolar set and in the second some other chromosomes in the complement were missing. While the triploids produced a few seeds, on crossing with diploid or on open pollintation, no seed set was found in hyper- and hypotriploids.
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