CYTOLOGIA
Online ISSN : 1348-7019
Print ISSN : 0011-4545
Volume 43, Issue 2
Displaying 1-27 of 27 articles from this issue
  • P. N. Mehra, S. P. Choda
    1978 Volume 43 Issue 2 Pages 217-235
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    Cytological studies were carried out on 18 species of the genus Euphorbia, of which chromosome counts for five species are reported for the first time. The chromosome numbers in four other species of this genus are found to be at variance with the earlier reports. Of the 18 investigated species, 12 were found to be at different levels of ploidy, while 6 are at the diploid level. Abnormal meiotic behaviour (multivalents and univalents at diakinesis, laggards at A-I, sterility of pollen grains and formation of micropollen) is recorded in the two morphotypes of E. neriifolia collected from Chandigarh and Ahmedabad. Both of these exhibited the chromosome number 2n=90 but in the Chandigarh population 90 bivalents were observed in an occasional spore mother cell too at M-I. It is suggested that this taxon has probably arisen through hybridisation between E. royleana (n=60) and E. nivulia (n=30). On the basis of available data x=10 is suggested as the primary base number for the genus. It has been observed that sections Anisophyllum and Tithymallus are greatly diversified in regard to the basic chromosome number, while the section Euphorbium seems to be uniform in this respect. The role of polyploidy and aneuploidy in speciation and evolution of the genus has been stressed.
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  • A. B. Sapre
    1978 Volume 43 Issue 2 Pages 237-241
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    1. A revised and accurate picture of the karyotype of Aloe barbadensis Mill. (a member of the tribe Aloineae, family Liliaceae) is presented.
    2. The species is diploid with 2n=2x=14, comprising of 8 long and 6 short chromosomes. The karyotype is bimodal.
    3. Employing Adhikary's method to determine the centromere position, the chromosomes show nearly median, nearly submedian and nearly subterminal primary constrictions. Two long chromosomes, the L, and the L4, show a satellite each on their long arms.
    4. In meiosis, only one long chromosome, probably L1, is seen in association with the nucleolus. During pollen-mitosis the chromosomes do not show satellites.
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  • R. N. Gohil, A. K. Koul
    1978 Volume 43 Issue 2 Pages 243-247
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    Allium consanguineum Kunth. growing wild in the Himalayas is a diploid species with 2n=16. Gohil and Koul (1971) recorded its chromosome number and also described the details of meiosis in a normal and a desynaptic clone.
    During the course of further work on this species some plants were isolated from one of the population in which quadrivalents, hexavalents, trivalents and univalents were observed during metaphase I. These plants are heterozygous for more than one interchange. The multivalents oriented non-disjunctionally resulting in total sterility. These plants propagate through underground bulbs and thereby conserve their hybridity.
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  • Edmundo José de Lucca, Margarida Lopes Rodrigues de Aguiar
    1978 Volume 43 Issue 2 Pages 249-253
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    The karyotypes of four species of Columbiformes have been analysed. The use of the karyotypes as a tool to help solving the problem of systematic classification is discussed. The cytogenetic date obtained agree with the separation of C. picui, in the Columbina genus, from C. minuta, C. passerina and C. talpacoti, in the Columbigallina genus.
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  • S. S. Raghuvanshi, D. N. Singh
    1978 Volume 43 Issue 2 Pages 255-264
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    Comparative karyokinetic response of 2n and 4n Trigonella foenum-graecum to gamma rays has been discussed. There is inverse correlation between ploidy level and stimulatory dose. Maximum availability of metabolites due to radiations stimulation in 2n at 60 krad has been suggested as a cause of excessive stimulation. Peaks have been observed in growth., dividing cell and aberration frequency. Cellular heterogenity with regard to radiosensitivity have been discussed. The differential assortment of cells carying aberrations is one of the reason of getting peaks in aberration. Certain biochemical or physiological factor accounts for differential sensitivity of 2n and 4n. Replication of DNA has been supposed to be one of the factor for slower growth rate and division frequency in 4n. Correlative study of ICV and radio-sensitivity have been made which reveals that despite larger ICV the 4n are radioresistant at the parameter of growth, dividing cells and initiation of second-ary roots although aberration frequency is higher in 4n. Higher ICY may explain greater chromosomal damage in tetraploids.
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  • V. Saran, Georgeta Lazãr-Keul
    1978 Volume 43 Issue 2 Pages 265-271
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    In vorliegender Arbit wurden die Beziehungen zwischen Wachstumbzw. Länge der Gerste-Wurzelhaare and der Geschwindigkeitszunahme der Protoplasmaströmung untersucht. Während der frühen Wachstumsphase sind die Wachstumsrate der Wurzelhaare and die Zunahme der Strömungsgeschwindigkeit eng miteinander korreliert. Nach Beendigung der großen Periode des Wachstums bestehen keine Beziehungen zwischen Zellwachstum and Strömungsgeschwindigkeit. Die Erklärung für die mit dem Wachstum der Wurzelhaare korrelierte Zunahme der Strömungsgeschwindigkeit muß eher mit den biochemischen Veränderungen während Wachstum and Alterung als in der mechanischen Dehnung des Cytoplasmas gesucht werden.
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  • IV. Subfamily Panicoideae; tribes Andropogoneae and Maydeae
    J. Christopher
    1978 Volume 43 Issue 2 Pages 273-287
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    Results of cytological studies on 48 species representing 30 genera belonging to the tribes Andropogoneae and Maydeae are presented in this paper. The basic chromosome numbers recorded are 5 (or 10) in 37 species, 7 in one species, 8 in 5 species and 9 in 5 species. It has been suggested that 5 may be regarded as the primary basic number of these two tribes. The basic number 10 was derived from 5 primarily through allopolyploidy and the other basic numbers were of secondary origin from 10. The highly specialised tribe Maydeae are a natural extension of the tribe Andropogoneae. The three tribes Paniceae, Andropogoneae and Maydeae belonging to the subfamily Panicoideae resemble each other in many respects and it is probable they originated from the same ancestral stock with the primary basic number 5.
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  • K. Ramachandran
    1978 Volume 43 Issue 2 Pages 289-303
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    Cytology of 30 species (including several varieties) coming under 17 genera of the Araceae, mostly from South India has been studied. Chromosome numbers determined in the present study range from 2n=16 to 2n=112.
    Meiotic studies of 11 species and some varieties have been made. Caladium bicolor showed chromatid bridges and fragments at anaphase I. The tetraploid race of Typhonium divaricatum formed six to nine rings of four chromosomes at diakinesis. Pentaploid race of this species showed chains of five chromosomes and rings of four. Meiosis was largely regular in the other species studied. Aberrations in microsporogenesis reported previously in diploid Colocasia antiquorum have not been found in plants of this species examined in the present study. Diploids of C. antiquorum and C. esculenta showed regular meiosis and seed formation. The embryos which abort under natural conditions have been grown in culture medium.
    Chromosome numbers determined in the present study and those reported previously in the family reveal the presence of a continuous series of basic numbers between x=8 and x=18. However, 22 out of 50 genera known cytologically so far have chromosome numbers in multiples of 14. In view of the low haploid numbers n=8 observed in two genera, x=14 is presumed to have been derived from the lower x=7 by doubling. The number 7 is suggested as the ancestral basic number of the family. It appears that aneuploid changes of chromosome numbers produced basic numbers of x=6, 7, 8, 9 and 10 in the early evolution of the family, after which polyploidy and dibasic amphidiploidy gave rise to the higher basic numbers (x=12 to 18) now found in the family.
    Karyotypes in the family also show differences in absolute chromosome size indicating changes in nuclear DNA in evolution. No definite trend of either phylogenetic increase or decrease of chromosome size is indicated by the available data. Reduction in size of chromosomes appears to have been an adaptation to an aquatic habitat in some genera.
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  • Sumitra Sen
    1978 Volume 43 Issue 2 Pages 305-315
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    Eleven species of the genus Lilium growing mainly in Eastern and Western Himalayan regions have cytologically been studied. This genus represents a homogenous group having 2n=24 chromosomes in all the species studied excepting L. japonicum and L. tigrinum which show thirty-six chromosomes. Differences in morphology of chromosomes have been indicated between various species and their unrecorded characteristics have been emphasized. Karyotype alterations involving not only nucleolar as claimed previously but non-nucleolar chromosomes too at inter- and intraspecific level are operating in evolution of different taxa of Lilium.
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  • Sima Bhattacharya (Nee Pal)
    1978 Volume 43 Issue 2 Pages 317-324
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    Cytological studies on five Indian taxa belonging to 4 species of the genus Salvia had been carried out. The chromosome numbers range from 2n=22 to 2n=44. The chromosomes are short ranging between 0.8-2.8μ. Both in the somatic and meiotic cells high frequencies of irregularities had been noticed and one of them was found in S. splendens i.e. occurrence of polyspory during meiosis. Evolutionary trend of these taxa within the genus was also discussed.
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  • I. Effects of acetylcholine, red light and far-red light upon the protoplasts of root tip meristem
    Hideo Toriyama
    1978 Volume 43 Issue 2 Pages 325-337
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    The available information concerning the effects of ACh, red light and far-red light upon the protoplasts of mung bean (Phaseolus aureus) root tip may be summarized as follows.
    1. By the application of a combination of Lillie's buffered neutral formalin fixing together with methyl blue staining, 1) one kind of pericyclic cells, 2) small cells outside of pith, and 3) the procambial cylinder of primary root and also 4) the primordia of the lateral root showed blue color deeply.
    2. On the transverse section of the central cylinder of 1000μ from the primary root apex, there are five to eight pericyclic cells in which the protoplasts are stained deeply with methyl blue; these cells contracted with 10-5 M and/or 10-4 M ACh.
    3. Atropine restrains the action of ACh on these pericyclic cells.
    4. In the same part of the root, there are three to five pericyclic cells in which protoplasts are barely stained with the same dye; these cells are not contracted by the ACh solution.
    5. In the same part of the root, the protoplasts of the central cylinder, especially the pericyclic cells, are contracted with the irradiation by red light for 4 min after that by far-red light for 4 min.
    6. Due to the irradiation with far-red light for 4 min after irradiation with red light, the features of the protoplast in the same tissue-cells of the central cylinder appears the same as the features of the material which was kept in darkness.
    7. The behaviour of the protoplasts of the procambial cylinder of the primary root and of the lateral root due to treatment with ACh and/or the irradiation with red light and with far-red light was the same as that of the protoplasts of the peri-cyclic cells which were stained with methyl blue.
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  • K. A. Mujeeb, R. F. Waters, L. S. Bates
    1978 Volume 43 Issue 2 Pages 339-343
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    A rapid, accurate feulgen method common for both cereal root tip and embryo squashes is described. The technique allows for improved chromosome detail, cell and chromosome spreads, and ease of making preparations permanent.
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  • K. K. Jain
    1978 Volume 43 Issue 2 Pages 345-349
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    Six contrasting morphological ‘variants’ in Plantago major Linn. were selected from the Kashmir Himalayas to investigate the causes of this intraspecific variation. Transplant experiments confirmed the hereditary nature of this variation, Meiosis and chromosome morphology was investigated in order to find out if these variants could be distinguished on a cytological basis. Meiosis was normal and the chromsome morphology was found to be similar in all the ‘variants’ indicating thereby that the diversity distinguishing the variants has been produced by simple genic differences. Polymorphism in P. major L. has been proposed to be controlled mainly through quantitative polygenic inheritance and partly through genic mutations.
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  • Mitsuharu Miyawaki, Yoko Taketomi
    1978 Volume 43 Issue 2 Pages 351-355
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    The cells of androgenic glands of the crayfish, Procambarus clarki, were examined by means of electron microscopy, and the occurrence of an enormously extended perinuclear space was indicated. In this space were a great number of inclusion bodies which have a limiting membrane. They contained fine ribosomelike particles. The inclusion bodies seem most likely to develop by inversion of portions of the granular endoplasmic reticulum.
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  • Rani Gupta, P. K. Gupta
    1978 Volume 43 Issue 2 Pages 357-369
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    Karyotypic analyses were made using root tip mitoses in 29 collections representing 27 species of the genus Crotalaria (Leguminosae). It was found that karyotype asymmetry was of a low order. It was also concluded that if C. incana with 2n=14 is derived from the taxa having 2n=16, a secondary trend from asymmetric to symmetric karyotype will have to be presumed. Since karyotypic differences could be found within a species, minor differences in karyotype should not be considered to have a strong bearing on taxonomy without giving due consideration to morphological differences.
    It was concluded that evolution in the genus must have taken place due to changes in individual genes or gene complexes due to mutations or gene recombinations. Structural changes in chromosomes, if any, did not change the karyotypes in any significant manner.
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  • Nagib M. A. Nassar, Margarida L. R. de Aguior
    1978 Volume 43 Issue 2 Pages 371-376
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    The study of the somatic complement of Nothoscordum fragans showed the occurrence of mosaicism in root tips. Besides common biotype 2n=13m+6t, cells with different chromosome constitutions were found: 2n=12m+8t, 2n=12m+6t. It is assumed that these complements were derived from the 2n=19, by centric fission in the first case and elimination of a m chromosome in the second one. Preliminary observations of meiosis showed different chromosome constitutions in Anaphases II.
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  • V. G. Narsinghani, Sudhir Kumar
    1978 Volume 43 Issue 2 Pages 377-381
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    The mutagens EMS and MMS induced various types of chlorophyll mutations in M2 and M3 generations. A high sterility was noticed in these induced chlorophyll mutants. The GA post-mutagenic treatment reduced the frequency and modified the spectrum of these chlorophyll mutations in M2 and M3 generations.
    The sterility induced by EMS and MMS in M1 generation continued to appear in M2 and M3 generations. Further, the GA treatment increased the pollen fertility in both EMS and MMS during M1 but this effect was neither seen in M2 nor M3 generations.
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  • S. C. Verma, R. K. Mittal
    1978 Volume 43 Issue 2 Pages 383-396
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    The common garlic, Allium sativum L. (2n=16), occurs basically as three morphotypes-H, U and A types (Table 1), all exclusively vegetatively reproduced. Five karyotypes from five bulbs of the A type have been analysed in detail to make a case study to discover if there is any necessity for extensive observations on a wide variety of material. The chromosome information thus revealed is compared also with that of Konivicka and Levan (1972) for H and U types. This study has amply impressed upon the need to undertake extensive chromosome studies of A. sativum.
    Within A type and between H, U and A types, wide variations occur in respect of the chromosome metrics, including arm ratios, particularly involving the nucleolar chromosomes. There are invariably two nucleolar pairs, and both are of the Sativum type, and generally, either one or both the pairs are heterozygous. Amongst the non-nucleolar chromosomes, chromosome nos. 3 and 8 are usually heterozygous. The probable sources of variation are discussed, and it is proposed that, besides structural alterations, general variability in respect of size and total chromosome length may be caused by differences in the stored food in the cloves, which in turn is affected by nutritive conditions of the soil. The proposal needs to be verified experimentally.
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  • Maria Luiza Silveira Mello, Heloisa H. Raymundo, Maria Christina M. Pr ...
    1978 Volume 43 Issue 2 Pages 397-404
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    Chromatin properties which reflect availability of DNA phosphates unattached to proteins and DNP conformation were studied in onion root tip cells subjected to hycanthone treatment. The hycanthone action at various drug concentrations was monitored by detecting chromosome aberrations and changes in mitotic index frequencies.
    The spectral shifts and changes in anisotropy patterns found in hycanthone-treated cells stained with a toluidine blue solution at pH 4.0 indicate decreased availability on free DNA phosphates and some uncoiling of the DNA helix promoted by the drug. The data are suggestive of attachment of at least one of the nitrogen groups of intercalated hycanthone molecules to DNA phosphates.
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  • L. A. AI-Sheikh Hussain, T. T. Elkington
    1978 Volume 43 Issue 2 Pages 405-410
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    The Giemsa C-band and quinacrine banded somatic karyotypes of diploid and triploid Allium caeruleum have been investigated. The diploid karyotype (2n=16) comprises 8 pairs of metacentric to submetacentric chromosomes; C-bands are absent from one pair, two pairs have chromosomes with one telomeric band and 5 pairs have bands at each telomere, including the two pairs with satellites which are positively stained. These chromosomes also has a band proximal to the nucleolar constriction. The triploid karyotype (2n=24) can be divided into 8 groups of 3 chromosomes with morphology and banding patterns closely corresponding to the 8 pairs of the diploid. Quinacrine stained preparations show a similar pattern of telomeric bands at late prophase. Observations of metaphase I in meiosis of PMCs show that a majority of cells (57%) have 8 trivalents while 34% have 7 trivalents. These observations suggest that the triploid is an autopolyploid derivative of the diploid A. caeruleum.
    The C-band pattern of this species is also compared with those of species in other sections of the genus.
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  • F. B. Kulfinski, A. J. Pappelis
    1978 Volume 43 Issue 2 Pages 411-414
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    Inner epidermal tissue of onion bulb-scale was studied by means of quantitative interference microscopy at the time of inoculation (with Aspergillus niger) and again after 48 hours of incubation. Nuclear area (NA), dry mass per unit area (DM/A) and nuclear dry mass (NDM) of epidermis cells 15-20mm ahead of mycelium were not statistically different from cells initially removed from the inoculation site. NDM of cells immediately ahead of advancing mycelium (0-5mm from the inoculation site) averaged 42% lower than that of cells obtained at the time of inoculation; NA was 46% lower; whereas, DM/A was 8% higher. We conclude that either sample of inner epidermal tissue, one removed from the inoculation site at the start of an experiment or one from 15-20mm away from the inoculation site 48 hours after the start of the experiment, is an appropriate control for determining the degree of host response to a pathogen within 0-5mm of the mycelium. The alteration and killing of host cells ahead of advancing mycelium suggested secretion of toxic metabolites by the fungus.
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  • I. Meiotic anomalies
    R. B. Katiyar
    1978 Volume 43 Issue 2 Pages 415-421
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    Dormant dry seeds of an erectly oriented fruit variety of Capsicum annuum were irradiated with gamma-rays from 60Co source at 5, 10, 15 and 20 kR dose levels. The plants grown from treated and control seeds were investigated for meiotic abnormalities and pollen sterility in M1 and M2 generations. Abnormal chromosomes included stickiness, clumping, altered association, breakage, bridges, unequal segregation, laggards and abnormal microspores and their frequencies were dosedependent. Pollen sterility increased with increase in dose. The per cent frequencies of anomalies were more numerous in M1 than M2, which could be due to the operation of recovery mechanisms or elimination of damaged chromosomes in the intervening period.
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  • Egbert W. Henry
    1978 Volume 43 Issue 2 Pages 423-432
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    Etiolated Alaska pea (Pisum sativum) stem sections (10mm) undergo cellular swelling, with attendant alterations in the cell-wall microfibrillar pattern when treated for 24 hr with 25 ppm ethylene. In addition, the ethylene-treated tissue exhibits altered morphology in terms of having intercellular spaces with microfibrillar orientation similar to that of the cell-walls.
    Ethylene-treated tissue exhibits a ring-shaped nucleolus in comparison to the normal, more compact type of nucleolus, usually present in nuclei.
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  • T. P. Wu
    1978 Volume 43 Issue 2 Pages 433-440
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    The detailed morphology of the pachytene chromosomes of Sorghum nitidum with one accessory chromosome (2n=10A+1B) has been analyzed. The characteristics of each of the five pachytene bivalents in the haploid complement and the pachytene accessory chromosome are identified on the basis of total length, arm ratio, and the extent of the heterochromatic region. Based on the data derived from the pachytene analysis, the possible origin of the accessory chromosome is discussed.
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  • F. B. Kulfinski, R. A. Katsanos, A. J. Pappelis
    1978 Volume 43 Issue 2 Pages 441-443
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    Although interference microscopy indicates that onion epidermal cells adjacent to cut margins decline in NDM (nuclear dry mass) by an average of 48%, the present study indicates no differences among nuclei beyond the nucleus of the second cell. Therefore, only nuclei of the extreme margin of cut tissue or internal nuclei exhibiting pycnotic symptoms (perhaps due to handling) need be avoided in sampling. This permits a greater proportion of a piece of tissue to be used in experimentation than was formerly considered feasible (Kulfinski and Pappelis 1975).
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  • Prasad R. K. Koduru, M. Krishna Rao
    1978 Volume 43 Issue 2 Pages 445-452
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    In an inbred line of Pennisetum typhoides Stapf et Hubb. (2n=14) being maintained by regular selling, several tetraploids and one triploid were located. Some of the tetraploids were moderately fertile but one tetraploid and the triploid were highly sterile. Chromosome pairing was studied in detail in these polyploids and their progeny as well as in their diploid sibs. The results presented in this indicate that 1) the differences in pairing among the sibs can be attributed to the segregation of desynaptic gene combinations, and 2) that polyploid types originated from cytological errors in diploids.
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  • I. Nishiyama, T. Yabuno
    1978 Volume 43 Issue 2 Pages 453-466
    Published: May 25, 1978
    Released on J-STAGE: March 19, 2009
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    A diallel cross was made using ten polyploid species, 2x, 4x, and 6x, x=7, in the genus Avena. Inmost crosses hybrid seeds were successfully obtained though the frequency of seed set varied greatly. The development of hybrid seeds differed widely between cross combinations, especially in reciprocal crosses. Hybrid seeds were classified into four types, 1) normal kernels, well developed and germinable (designated as D+), 2) shrivelled-empty kernels which do not germinate (E-), 3) small viable kernels (Rd+) and 4) small inviable kernels (Rd-). Some intermediate types were occasionally found.
    The results are fairly well explained in terms of a hypothesis of polar-nuclei activation in which the strength of the activating action of the male nucleus, and the reaction of the female nucleus is expressed by terms ‘activating value (AV)’ and ‘response value (RV)’, respectively. The degree of seed failure is closely related to the difference between the activating and response values, expressed by the activation index, AV/2RV (or×100) of the polar nuclei. In a selfed plant the activation index (AI) of the polar nuclei is 1/2=0.5 (or 50%), and this usually being the normal index results in the production of normal seeds. If AI deviates from 50 per cent the development of endosperm is often arrested or aborted.
    Based on the degree of abnormality of hybrid kernels, activating values of the ten species are arbitrarily assigned from 0.4 in A. ventricosa(2x) to 3 in A. sterilis(6x) compared with 1 in A. strigosa(2x) as the standard. Among 74 reciprocal interspecific crosses the AI of the polar nuclei varied widely from 7 to 375 per cent. The distribution of these indices agrees closely with the grouping of the four kernel types. Thus, AI values of less than 20, 20-30, 30-80, and more than 80 per cent show the Rd-, Rd+, D+ and E- kernel types, respectively. In other words, if the AV of the pollen parent is >160 or <40 per cent that of the maternal parent they are cross-incompatible. Thus in double fertilization of angiosperms the triple fusion of two polar nuclei with a secondary male nucleus is apparently a biological isolation mechanism and may be the most effective barrier to hybridization on occasion.
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