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1

Standard and C-banded meiotic karyotypes of Psylloidea (Sternorrhyncha, Homoptera, Insecta)

100%

Maryanska-Nadachowska A. , Kuznetsova V. , Nokkala S.

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nr 1-2

53-62

EN

Meiotic karyotypes were studied in males of Craspedolepta sonchi (Foerster, 1848), Diaphorina chobauti Puton, 1898, D. lamproptera Burckhardt, 1981, Psylla hartigii Flor, 1861, Cacopsylla palmeni (Loew, 1878), C. hippophaes (Foerster, 1848), C. melanoneura (Foerster, 1868), C. pyricola (Foerster 1848), C. moscovita (Andrianova, 1848), Bactericera salicivora (Reuter, 1876), Trioza abdominalis Flor, 1861, T. lauri = Lauritrioza alacris (Flor, 1861). Karyotypes were 2n = 25 (24 + XO) in all species except B. salicivora with 2n = 26 (24 + neo-XY). Testes consisted of two follicles each in all species but P. hartigii with four-follicular testes in males. The discussion covers the problems of chromosome numbers, sex-determining chromosome systems, B-chromosomes, patterns of C- banding, testis structure, and spermatid development in Psylloidea.

2

Cytogenetic studies of Glomeris (Diplopoda: Glomeridae)

88%

Warchalowska-Sliwa E. , Maryanska-Nadachowska A. , Kania G.

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tom 52

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nr 1-2

67-71

EN

Karyotypes and meiosis of Glomeris hexasticha and G. connexa (Diplopoda: Glomeridae) from Poland were described using C-heterochromatin distribution and observations of the location of NORs. These species were characterized by 2n>=16 and the XY sex determination system. Differences were found in the amount of C-heterochromatin in X and Y chromosomes between the studied species. In G. hexasticha, supernumerary B chromosomes were described.

3

Karyotypes and chromosome rearrangements in two tribes of weevils (Coleoptera, Curculionidae: Sciaphilini and Brachydrini)

75%

Lachowska D.

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nr 3-4

219-225

EN

A description of karyotypes in two tribes of weevils, Sciaphilini and Brachyderini, was carried out with a discussion on the main trends of chromosomal evolution occurring in these groups. Some important cytological characteristics, such as chromosome morphology, sex determination type, pattern of male meiosis, B chromosome occurrence, as well as C-heterochromatin, NOR localization, and fluorochrome AT and GC specific staining are presented. The chromosome numbers and morphology in the two tribes of weevils are highly conserved. With the exception of one species, all possessed a diploid number of 22 chromosomes or triploid number of 33 chromosomes. Constitutive heterochromatin was observed in the pericentromeric regions of themajority of the chromosomes. In some species, additional constitutive heterochromatin was also observed in interstitial positions. The study of meiotic cells revealed the occurrence of total synapsis between autosomes, the presence of one terminal, interstitial or two chiasmata, reductional behaviour and regular segregation of all chromosomes, as well as the formation of associations of the Xyp type in sex chromosomes. Testicular cells impregnated with silver nitrate demonstrated NORs localized on autosomes and argentophilic material in the space between the X and y chromosomes. The use of CMA3/DAPI staining showed that centromeric heterochromatin is AT-rich, whereas CMA3 bands were probably conincident with NOR sites.

4

The course of meiosis, pollen fertility and seed setting in barley lines with duplications in chromosomes 6 and 7

75%

Sodkiewicz T. , Sodkiewicz W.

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nr 4

231-240

EN

The aim of the present study was to find the reasons a low fertility of plants with duplicated segments of the short arms of satellited chromosomes.An attempt was made to determine the influence of duplicated segments of different size on the course of meiotic division, pollen stainability and viability as well as to evaluate the influence of these traits on seed setting in barley lines carrying duplications.Material for the study were spring barley (Hordeum vulgaris) lines, derived from the cv.Bonus with structural changes in chromosomes 6 and 7.It was found that percentage of bivalents formed in the course of meiotic division is correlated with the size of a duplicated sector.The formation of quadrivalent chromosome linkages in the course of meiosis was observed in the lines with duplications, and the number of quadrivalents per cell increased with an enlarged size of a duplicated chromosome sector.Seed setting in the lines carrying duplications may be negatively affected by a small amount of pollen grains in the anthers.Per cent of fertile flowers in the group of lines with duplications was not directly correlated either with per cent of viable pollen grains or with the size of a duplicated sector.

5

The behaviour of a multiple sex chromosome system in Dundocoris flavilineatus (Heteroptera: Aradidae: Carventinae) that originated by autosome-sex chromosome fusion

75%

Jacobs D. H.

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2002

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tom 51

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nr 1-2

23-32

EN

The nominate subspecies of Dundocoris flavilineatus Jacobs occurs in indigenous evergreen forests over a wide area in KwaZulu-Natal and the Eastern Cape Province of South Africa. It has a chromosome number of 2n = 28XY, which is the ancestral number for the genus. D. flavilineatus ndabeniensis, which comprises an isolated sibling population at Ndabeni forest in northern KwaZulu-Natal, possesses a multiple sex chromosome system, presumably a X1X2Y system and has a chromosome number of 2n = 27X1X2Y. The system probably originated when an autosome and the Y-chromosome of the 28XY karyotype fused. In contrast to the situation previously described in the XY1Y2 system of D. nodulicarinus the autosomal and original Y-chromosome parts of the neo-Y chromosome seem to have a reciprocal influence on each other in terms of structure and staining intensity during prophase I. The autosomal part of the neo-Y adopts a granulate, heteropycnotic, linear structure while the original Y part is less globular than usual in structure. The neo-X chromosome (= X2) behaves like, and stays isopycnotic with the autosomes. It is connected to the neo-Y by terminal association ? probably a terminal chiasma. The sex chromosome system is post-reductional and a sex chromosome trivalent is present in all metaphase II cells. The origin and behaviour of the neo-X1X2Y sex chromosome system in D. flavilineatus ndabeniensis are described, discussed, illustrated with photomicrographs and compared to the XY1Y2 system in D. nodulicarinus. Idiograms of the karyotypes of the two subspecies of D. flavilineatus are also presented.

6

A comparative analysis of the rate of meiosis, chiasma frequency and terminalization in the Jerboas Allactaga and Jaculus (Rodentia: Dipodidae) in Egypt

75%

Ata A. T. M. , Shahin A. A. B. , Allam H. Z.

Folia Biologica

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2001

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tom 49

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nr 3-4

129-135

EN

The rate of seven meiotic stages (zygotene-pachytene, diplotene-diakinesis, metaphase I, anaphase I, metaphase II, anaphase II, and quartet) was studied in the jerboas Jaculus jaculus jaculus, Jaculus orientalis, and Allactaga tetradactyla, chiasma frequency and terminalization being examined only in J. jaculus and J. orientalis, and compared with the previous data concerning A. tetradactyla. Significant differences in the rate of meiosis, frequency of bivalent types, and frequency of interstitial and distal or terminal chiasmata per genome length were observed between A. tetradactyla and the two congeneric species J. jaculus and J. orientalis. Differences of these parameters among individuals within each species are also discussed in detail.