摘要:

Hydroxylammonium sulphate (HAS) and maleic hydrazide (MH) have been administered through larval feeding to study their effects on salivary chromosomes ofDrosophila.Both the chemicals have been tested in this organism, perhaps, for the first time. HAS is 3.2 times potential than MH in inducing inversions. Both the chemicals show resemblance in not affecting 2L chromosome and in inducing some identical inversions. In contrast to hydroxylamine (HA), HAS is a potential chromosome breaking agent inDrosophila.The loci showing high break frequency, have been suggested as the sites of intercalary-heterochromatin.

ISSN:0008-7114    

DOI:10.1080/00087114.1978.10796725

出版商:Taylor & Francis    

年代:1978

数据来源: Taylor

摘要:

The study of the somatic complement ofN. fragransshowed the accurence of multiple karyotypes in the same plant 2n=18, 2n=19 and 2n=20 with different frequencies. Chromosome fragmentation was recorded. It is assumed that the 2n=18 and 2n=20 are derived from 2n=19, by centric fission in the first case and elimination of m chromosome in the second case.

ISSN:0008-7114    

DOI:10.1080/00087114.1978.10796726

出版商:Taylor & Francis    

年代:1978

数据来源: Taylor

摘要:

The duration of different stages of meiotic prophase at 23 ± 1 °C has been measured in cultured meiocytes of lily (Lilium longifiorum), Wheat (Triticum aestivum)and barley (Hordeum vulgare) in presence and absence of protein inhibitors when added in basic culture media. Meiocytes of lily show variable growth patterns depending upon the stage of explantation in culture. In absence of the inhibitor, meiotic prophase in culture continues for 6 days in lily, about 16.5 hrs in wheat and about 28.5 hrs in barley. However, the duration of the meiotic prophase is much extended in presence of the inhibitors in all the three experimental systems. A certain amount of asynchrony in the growing meiocytes is caused through the introduction of the inhibitors into the growth media along with occurrence of cytological abnormalities.

ISSN:0008-7114    

DOI:10.1080/00087114.1978.10796727

出版商:Taylor & Francis    

年代:1978

数据来源: Taylor

摘要:

Des nombres chromosomiques nouveaux sont rapportés pour des espèces Africaines des genresMicrogoniumDesv. etDidymoglossumPresl. Dans le genreMicrogonium, l'apomixie peut s'exprimer, dans une même population et dans un même individu, par toutes les formes connues d'apogamie chez les ptéridophytes. Dans ces complexes apomictiques, l'aneuploïdie et des nombres chromosomiques ÉlevÉs ont ÉtÉ mis en Évidence.

ISSN:0008-7114    

DOI:10.1080/00087114.1978.10796728

出版商:Taylor & Francis    

年代:1978

数据来源: Taylor

摘要:

The effect of RNA synthesis inhibition on the progress of mitosis was studied in meristematic cells ofAllium cepaat the ultrastructural level. The continuous treatment with 3'AdR and EB on cells which are in the beginning of mitosis, causes the persistence of the nuclear envelope (GONZALEZ-FERNANDEZet al.1970) without blocking the chromosomal cycle (RISUEÑOet al.1975). In the case of EB there are ruptures in some points of the nuclear envelope but with 3'AdR it is still intact.

ISSN:0008-7114    

DOI:10.1080/00087114.1978.10796729

出版商:Taylor & Francis    

年代:1978

数据来源: Taylor

摘要:

Several new finds of the mole rat have been recorded, namely—Lefkothea, Eleousai, Pelasgia, Modion, Molos and Hag. Spyridon, where the first two are at the same time the farthest westbound finds recorded so far in Greece. Considered are ecogeographical distribution range and the phenomenon of disappearance of certain mole rat populations from Greece. Presented aie karyotype descriptions of the mole rat population Lefkothea (2n=56, NF=84, NFa=80) from the northwest and Hag. Spyridon population (2n=58, NF=88, NFa=84) from the southeast of Greece. Established is the existence of groups of chromosomes characteristic for the entire genusSpdax.

ISSN:0008-7114    

DOI:10.1080/00087114.1978.10796730

出版商:Taylor & Francis    

年代:1978

数据来源: Taylor

摘要:

In the study carried out on tissue cultures obtained from the mesocotyl part of the two diploid strains ofZea mays—SII04 and H-3, the difference in variances of nuclear dimensions between different subcultures in each strain has proved to be highly significant.

ISSN:0008-7114    

DOI:10.1080/00087114.1978.10796731

出版商:Taylor & Francis    

年代:1978

数据来源: Taylor

摘要:

Thuringiensin-A, an exotoxin fromBacillus thuringiensisinhibits cell plate formation and causes bimitosis in the ensuing binucleate cells, a comparatively unfamiliar cellular response. This seems to be only chemical capable of affecting both spindle and cytokinesis. The microtubular systems are probably affected. The results suggest the potentiality of Thuringiensin-A as a tool for cell cycle analysis by marking out binucleate cells.

ISSN:0008-7114    

DOI:10.1080/00087114.1978.10796732

出版商:Taylor & Francis    

年代:1978

数据来源: Taylor

摘要:

Alterations in chromosomal morphology and staining affinity were produced in mouse embryo cells afterin vivoexposure to 2000 mg/kg BrdU on day 10 of gestation. Treated females were killed either 2, 4, or 6 h after BrdU administration and embryo cells were cultured in a colcemid-containing medium for 2 h. Chromosomes exposed to BrdU for 2 h showed centromeric regions that were lightly stained by the Giemsa technique. After 4 h treatment, both centromeric and non-centromeric regions were affected with both decreased staining affinity and a loss of chromosome compactness being observed. After 6 h exposure, lighter Giemsa staining was observed throughout the chromosomes and there was an indication of chromosomal segmentation.

ISSN:0008-7114    

DOI:10.1080/00087114.1978.10796733

出版商:Taylor & Francis    

年代:1978

数据来源: Taylor

摘要:

Somatic karyotype, meiotic stages and G-banded chromosomes ofMus saxicola sadhu(Muridae:Rodentia) are described. The results are discussed on the basis of earlier data on related forms.

ISSN:0008-7114    

DOI:10.1080/00087114.1978.10796734

出版商:Taylor & Francis    

年代:1978

数据来源: Taylor